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Java-taulukot

Normaalisti taulukko on kokoelma samantyyppisiä elementtejä, joilla on vierekkäinen muistipaikka.

Java-joukko on objekti, joka sisältää samantyyppisiä elementtejä. Lisäksi taulukon elementit tallennetaan viereiseen muistipaikkaan. Se on tietorakenne, johon tallennamme samanlaisia ​​elementtejä. Voimme tallentaa vain kiinteän joukon elementtejä Java-taulukkoon.

Javan taulukko on indeksipohjainen, taulukon ensimmäinen elementti tallennetaan 0. indeksiin, 2. elementti 1. indeksiin ja niin edelleen.

Toisin kuin C/C++, voimme saada taulukon pituuden käyttämällä pituusjäsentä. C/C++:ssa meidän on käytettävä sizeof-operaattoria.

Javassa array on dynaamisesti luodun luokan objekti. Java-taulukko perii Object-luokan ja toteuttaa sarjoitettavat ja kloonattavat rajapinnat. Voimme tallentaa primitiivisiä arvoja tai objekteja taulukkoon Javassa. Kuten C/C++, voimme myös luoda yksiulotteisia tai moniulotteisia taulukoita Javassa.

Lisäksi Java tarjoaa anonyymien taulukoiden ominaisuuden, joka ei ole saatavilla C/C++:ssa.

Java-joukko

Edut

    Koodin optimointi:Se optimoi koodin, voimme hakea tai lajitella tiedot tehokkaasti.Satunnainen pääsy:Voimme saada kaikki tiedot, jotka sijaitsevat indeksipaikassa.

Haitat

    Kokorajoitus:Voimme tallentaa vain kiinteän koon elementtejä taulukkoon. Se ei kasva kokoaan ajon aikana. Tämän ongelman ratkaisemiseksi Javassa käytetään kokoelmakehystä, joka kasvaa automaattisesti.

Array-tyypit javassa

Matriisia on kahta tyyppiä.

  • Yksiulotteinen taulukko
  • Moniulotteinen Array

Yksiulotteinen taulukko Javassa

Syntaksi taulukon ilmoittamiseen Javassa

sql-määrä erillinen
 dataType[] arr; (or) dataType []arr; (or) dataType arr[]; 

Array:n ilmentäminen Javassa

 arrayRefVar=new datatype[size]; 

Esimerkki Java Arraysta

Katsotaanpa yksinkertaista esimerkkiä java-taulukosta, jossa aiomme julistaa, instantoida, alustaa ja kulkea taulukon läpi.

 //Java Program to illustrate how to declare, instantiate, initialize //and traverse the Java array. class Testarray{ public static void main(String args[]){ int a[]=new int[5];//declaration and instantiation a[0]=10;//initialization a[1]=20; a[2]=70; a[3]=40; a[4]=50; //traversing array for(int i=0;i <a.length;i++) length is the property of array system.out.println(a[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 20 70 40 50 </pre> <hr> <h2>Declaration, Instantiation and Initialization of Java Array</h2> <p>We can declare, instantiate and initialize the java array together by:</p> <pre> int a[]={33,3,4,5};//declaration, instantiation and initialization </pre> <p>Let&apos;s see the simple example to print this array.</p> <pre> //Java Program to illustrate the use of declaration, instantiation //and initialization of Java array in a single line class Testarray1{ public static void main(String args[]){ int a[]={33,3,4,5};//declaration, instantiation and initialization //printing array for(int i=0;i <a.length;i++) length is the property of array system.out.println(a[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 33 3 4 5 </pre> <h2>For-each Loop for Java Array</h2> <p>We can also print the Java array using <strong> <a href="/java-each-loop-enhanced">for-each loop</a> </strong> . The Java for-each loop prints the array elements one by one. It holds an array element in a variable, then executes the body of the loop.</p> <p>The syntax of the for-each loop is given below:</p> <pre> for(data_type variable:array){ //body of the loop } </pre> <p>Let us see the example of print the elements of Java array using the for-each loop.</p> <pre> //Java Program to print the array elements using for-each loop class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; //printing array using for-each loop for(int i:arr) System.out.println(i); }} </pre> <p>Output:</p> <pre> 33 3 4 5 </pre> <hr> <h2>Passing Array to a Method in Java</h2> <p>We can pass the java array to method so that we can reuse the same logic on any array.</p> <p>Let&apos;s see the simple example to get the minimum number of an array using a method.</p> <pre> //Java Program to demonstrate the way of passing an array //to method. class Testarray2{ //creating a method which receives an array as a parameter static void min(int arr[]){ int min=arr[0]; for(int i=1;iarr[i]) min=arr[i]; System.out.println(min); } public static void main(String args[]){ int a[]={33,3,4,5};//declaring and initializing an array min(a);//passing array to method }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> 3 </pre> <h2>Anonymous Array in Java</h2> <p>Java supports the feature of an anonymous array, so you don&apos;t need to declare the array while passing an array to the method.</p> <pre> //Java Program to demonstrate the way of passing an anonymous array //to method. public class TestAnonymousArray{ //creating a method which receives an array as a parameter static void printArray(int arr[]){ for(int i=0;i <arr.length;i++) system.out.println(arr[i]); } public static void main(string args[]){ printarray(new int[]{10,22,44,66}); passing anonymous array to method }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 22 44 66 </pre> <h2>Returning Array from the Method</h2> <p>We can also return an array from the method in Java.</p> <pre> //Java Program to return an array from the method class TestReturnArray{ //creating method which returns an array static int[] get(){ return new int[]{10,30,50,90,60}; } public static void main(String args[]){ //calling method which returns an array int arr[]=get(); //printing the values of an array for(int i=0;i <arr.length;i++) system.out.println(arr[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 30 50 90 60 </pre> <h2>ArrayIndexOutOfBoundsException</h2> <p>The Java Virtual Machine (JVM) throws an ArrayIndexOutOfBoundsException if length of the array in negative, equal to the array size or greater than the array size while traversing the array.</p> <pre> //Java Program to demonstrate the case of //ArrayIndexOutOfBoundsException in a Java Array. public class TestArrayException{ public static void main(String args[]){ int arr[]={50,60,70,80}; for(int i=0;i<=arr.length;i++){ system.out.println(arr[i]); } }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> Exception in thread &apos;main&apos; java.lang.ArrayIndexOutOfBoundsException: 4 at TestArrayException.main(TestArrayException.java:5) 50 60 70 80 </pre> <hr> <h2>Multidimensional Array in Java</h2> <p>In such case, data is stored in row and column based index (also known as matrix form).</p> <p> <strong>Syntax to Declare Multidimensional Array in Java</strong> </p> <pre> dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; </pre> <p> <strong>Example to instantiate Multidimensional Array in Java</strong> </p> <pre> int[][] arr=new int[3][3];//3 row and 3 column </pre> <p> <strong>Example to initialize Multidimensional Array in Java</strong> </p> <pre> arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; </pre> <h3>Example of Multidimensional Java Array</h3> <p>Let&apos;s see the simple example to declare, instantiate, initialize and print the 2Dimensional array.</p> <pre> //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+' '); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+' '); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+' '); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+' '); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){></pre></=arr.length;i++){></pre></arr.length;i++)></pre></arr.length;i++)></pre></a.length;i++)></pre></a.length;i++)>

Java Array:n julistus, ilmentäminen ja alustus

Voimme ilmoittaa, ilmentää ja alustaa java-taulukon yhdessä seuraavasti:

 int a[]={33,3,4,5};//declaration, instantiation and initialization 

Katsotaanpa yksinkertainen esimerkki tämän taulukon tulostamiseksi.

 //Java Program to illustrate the use of declaration, instantiation //and initialization of Java array in a single line class Testarray1{ public static void main(String args[]){ int a[]={33,3,4,5};//declaration, instantiation and initialization //printing array for(int i=0;i <a.length;i++) length is the property of array system.out.println(a[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 33 3 4 5 </pre> <h2>For-each Loop for Java Array</h2> <p>We can also print the Java array using <strong> <a href="/java-each-loop-enhanced">for-each loop</a> </strong> . The Java for-each loop prints the array elements one by one. It holds an array element in a variable, then executes the body of the loop.</p> <p>The syntax of the for-each loop is given below:</p> <pre> for(data_type variable:array){ //body of the loop } </pre> <p>Let us see the example of print the elements of Java array using the for-each loop.</p> <pre> //Java Program to print the array elements using for-each loop class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; //printing array using for-each loop for(int i:arr) System.out.println(i); }} </pre> <p>Output:</p> <pre> 33 3 4 5 </pre> <hr> <h2>Passing Array to a Method in Java</h2> <p>We can pass the java array to method so that we can reuse the same logic on any array.</p> <p>Let&apos;s see the simple example to get the minimum number of an array using a method.</p> <pre> //Java Program to demonstrate the way of passing an array //to method. class Testarray2{ //creating a method which receives an array as a parameter static void min(int arr[]){ int min=arr[0]; for(int i=1;iarr[i]) min=arr[i]; System.out.println(min); } public static void main(String args[]){ int a[]={33,3,4,5};//declaring and initializing an array min(a);//passing array to method }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> 3 </pre> <h2>Anonymous Array in Java</h2> <p>Java supports the feature of an anonymous array, so you don&apos;t need to declare the array while passing an array to the method.</p> <pre> //Java Program to demonstrate the way of passing an anonymous array //to method. public class TestAnonymousArray{ //creating a method which receives an array as a parameter static void printArray(int arr[]){ for(int i=0;i <arr.length;i++) system.out.println(arr[i]); } public static void main(string args[]){ printarray(new int[]{10,22,44,66}); passing anonymous array to method }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 22 44 66 </pre> <h2>Returning Array from the Method</h2> <p>We can also return an array from the method in Java.</p> <pre> //Java Program to return an array from the method class TestReturnArray{ //creating method which returns an array static int[] get(){ return new int[]{10,30,50,90,60}; } public static void main(String args[]){ //calling method which returns an array int arr[]=get(); //printing the values of an array for(int i=0;i <arr.length;i++) system.out.println(arr[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 30 50 90 60 </pre> <h2>ArrayIndexOutOfBoundsException</h2> <p>The Java Virtual Machine (JVM) throws an ArrayIndexOutOfBoundsException if length of the array in negative, equal to the array size or greater than the array size while traversing the array.</p> <pre> //Java Program to demonstrate the case of //ArrayIndexOutOfBoundsException in a Java Array. public class TestArrayException{ public static void main(String args[]){ int arr[]={50,60,70,80}; for(int i=0;i<=arr.length;i++){ system.out.println(arr[i]); } }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> Exception in thread &apos;main&apos; java.lang.ArrayIndexOutOfBoundsException: 4 at TestArrayException.main(TestArrayException.java:5) 50 60 70 80 </pre> <hr> <h2>Multidimensional Array in Java</h2> <p>In such case, data is stored in row and column based index (also known as matrix form).</p> <p> <strong>Syntax to Declare Multidimensional Array in Java</strong> </p> <pre> dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; </pre> <p> <strong>Example to instantiate Multidimensional Array in Java</strong> </p> <pre> int[][] arr=new int[3][3];//3 row and 3 column </pre> <p> <strong>Example to initialize Multidimensional Array in Java</strong> </p> <pre> arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; </pre> <h3>Example of Multidimensional Java Array</h3> <p>Let&apos;s see the simple example to declare, instantiate, initialize and print the 2Dimensional array.</p> <pre> //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+\' \'); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\' \'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\' \'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\' \'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){></pre></=arr.length;i++){></pre></arr.length;i++)></pre></arr.length;i++)></pre></a.length;i++)>

For-each Loop for Java Array

Voimme myös tulostaa Java-taulukon käyttämällä jokaiselle silmukalle . Java for-each -silmukka tulostaa taulukon elementit yksitellen. Se pitää taulukkoelementin muuttujassa ja suorittaa sitten silmukan rungon.

For-each-silmukan syntaksi on annettu alla:

 for(data_type variable:array){ //body of the loop } 

Katsotaanpa esimerkkiä Java-taulukon elementtien tulostamisesta for-each-silmukalla.

 //Java Program to print the array elements using for-each loop class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; //printing array using for-each loop for(int i:arr) System.out.println(i); }} 

Lähtö:

 33 3 4 5 

Array:n siirtäminen menetelmälle Javassa

Voimme siirtää java-taulukon metodille, jotta voimme käyttää samaa logiikkaa uudelleen missä tahansa taulukossa.

Katsotaanpa yksinkertainen esimerkki taulukon vähimmäismäärän saamiseksi menetelmällä.

 //Java Program to demonstrate the way of passing an array //to method. class Testarray2{ //creating a method which receives an array as a parameter static void min(int arr[]){ int min=arr[0]; for(int i=1;iarr[i]) min=arr[i]; System.out.println(min); } public static void main(String args[]){ int a[]={33,3,4,5};//declaring and initializing an array min(a);//passing array to method }} 
Testaa nyt

Lähtö:

 3 

Anonyymi array Javassa

Java tukee anonyymin taulukon ominaisuutta, joten sinun ei tarvitse ilmoittaa taulukkoa siirtäessäsi taulukkoa menetelmälle.

 //Java Program to demonstrate the way of passing an anonymous array //to method. public class TestAnonymousArray{ //creating a method which receives an array as a parameter static void printArray(int arr[]){ for(int i=0;i <arr.length;i++) system.out.println(arr[i]); } public static void main(string args[]){ printarray(new int[]{10,22,44,66}); passing anonymous array to method }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 22 44 66 </pre> <h2>Returning Array from the Method</h2> <p>We can also return an array from the method in Java.</p> <pre> //Java Program to return an array from the method class TestReturnArray{ //creating method which returns an array static int[] get(){ return new int[]{10,30,50,90,60}; } public static void main(String args[]){ //calling method which returns an array int arr[]=get(); //printing the values of an array for(int i=0;i <arr.length;i++) system.out.println(arr[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 30 50 90 60 </pre> <h2>ArrayIndexOutOfBoundsException</h2> <p>The Java Virtual Machine (JVM) throws an ArrayIndexOutOfBoundsException if length of the array in negative, equal to the array size or greater than the array size while traversing the array.</p> <pre> //Java Program to demonstrate the case of //ArrayIndexOutOfBoundsException in a Java Array. public class TestArrayException{ public static void main(String args[]){ int arr[]={50,60,70,80}; for(int i=0;i<=arr.length;i++){ system.out.println(arr[i]); } }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> Exception in thread &apos;main&apos; java.lang.ArrayIndexOutOfBoundsException: 4 at TestArrayException.main(TestArrayException.java:5) 50 60 70 80 </pre> <hr> <h2>Multidimensional Array in Java</h2> <p>In such case, data is stored in row and column based index (also known as matrix form).</p> <p> <strong>Syntax to Declare Multidimensional Array in Java</strong> </p> <pre> dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; </pre> <p> <strong>Example to instantiate Multidimensional Array in Java</strong> </p> <pre> int[][] arr=new int[3][3];//3 row and 3 column </pre> <p> <strong>Example to initialize Multidimensional Array in Java</strong> </p> <pre> arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; </pre> <h3>Example of Multidimensional Java Array</h3> <p>Let&apos;s see the simple example to declare, instantiate, initialize and print the 2Dimensional array.</p> <pre> //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+\' \'); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\' \'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\' \'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\' \'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){></pre></=arr.length;i++){></pre></arr.length;i++)></pre></arr.length;i++)>

Palautetaan taulukko menetelmästä

Voimme myös palauttaa taulukon Java-menetelmästä.

 //Java Program to return an array from the method class TestReturnArray{ //creating method which returns an array static int[] get(){ return new int[]{10,30,50,90,60}; } public static void main(String args[]){ //calling method which returns an array int arr[]=get(); //printing the values of an array for(int i=0;i <arr.length;i++) system.out.println(arr[i]); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 10 30 50 90 60 </pre> <h2>ArrayIndexOutOfBoundsException</h2> <p>The Java Virtual Machine (JVM) throws an ArrayIndexOutOfBoundsException if length of the array in negative, equal to the array size or greater than the array size while traversing the array.</p> <pre> //Java Program to demonstrate the case of //ArrayIndexOutOfBoundsException in a Java Array. public class TestArrayException{ public static void main(String args[]){ int arr[]={50,60,70,80}; for(int i=0;i<=arr.length;i++){ system.out.println(arr[i]); } }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> Exception in thread &apos;main&apos; java.lang.ArrayIndexOutOfBoundsException: 4 at TestArrayException.main(TestArrayException.java:5) 50 60 70 80 </pre> <hr> <h2>Multidimensional Array in Java</h2> <p>In such case, data is stored in row and column based index (also known as matrix form).</p> <p> <strong>Syntax to Declare Multidimensional Array in Java</strong> </p> <pre> dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; </pre> <p> <strong>Example to instantiate Multidimensional Array in Java</strong> </p> <pre> int[][] arr=new int[3][3];//3 row and 3 column </pre> <p> <strong>Example to initialize Multidimensional Array in Java</strong> </p> <pre> arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; </pre> <h3>Example of Multidimensional Java Array</h3> <p>Let&apos;s see the simple example to declare, instantiate, initialize and print the 2Dimensional array.</p> <pre> //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+\' \'); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\' \'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\' \'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\' \'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){></pre></=arr.length;i++){></pre></arr.length;i++)>

ArrayIndexOutOfBoundsException

Java-virtuaalikone (JVM) heittää ArrayIndexOutOfBoundsException-ilmoituksen, jos taulukon pituus on negatiivinen, yhtä suuri kuin taulukon koko tai suurempi kuin taulukon koko kulkiessaan taulukon läpi.

 //Java Program to demonstrate the case of //ArrayIndexOutOfBoundsException in a Java Array. public class TestArrayException{ public static void main(String args[]){ int arr[]={50,60,70,80}; for(int i=0;i<=arr.length;i++){ system.out.println(arr[i]); } }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> Exception in thread &apos;main&apos; java.lang.ArrayIndexOutOfBoundsException: 4 at TestArrayException.main(TestArrayException.java:5) 50 60 70 80 </pre> <hr> <h2>Multidimensional Array in Java</h2> <p>In such case, data is stored in row and column based index (also known as matrix form).</p> <p> <strong>Syntax to Declare Multidimensional Array in Java</strong> </p> <pre> dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; </pre> <p> <strong>Example to instantiate Multidimensional Array in Java</strong> </p> <pre> int[][] arr=new int[3][3];//3 row and 3 column </pre> <p> <strong>Example to initialize Multidimensional Array in Java</strong> </p> <pre> arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; </pre> <h3>Example of Multidimensional Java Array</h3> <p>Let&apos;s see the simple example to declare, instantiate, initialize and print the 2Dimensional array.</p> <pre> //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+\' \'); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\' \'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\' \'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\' \'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){></pre></=arr.length;i++){>

Moniulotteinen taulukko Javassa

Tällöin tiedot tallennetaan rivi- ja sarakepohjaiseen indeksiin (tunnetaan myös matriisimuotona).

Syntaksi moniulotteisen taulukon ilmoittamiseksi Javassa

 dataType[][] arrayRefVar; (or) dataType [][]arrayRefVar; (or) dataType arrayRefVar[][]; (or) dataType []arrayRefVar[]; 

Esimerkki moniulotteisen taulukon ilmentämisestä Javassa

 int[][] arr=new int[3][3];//3 row and 3 column 

Esimerkki moniulotteisen taulukon alustamisesta Javassa

 arr[0][0]=1; arr[0][1]=2; arr[0][2]=3; arr[1][0]=4; arr[1][1]=5; arr[1][2]=6; arr[2][0]=7; arr[2][1]=8; arr[2][2]=9; 

Esimerkki moniulotteisesta Java-taulukosta

Katsotaanpa yksinkertainen esimerkki 2-ulotteisen taulukon ilmoittamisesta, ilmentämisestä, alustamisesta ja tulostamisesta.

Android-sovelluksen lukitseminen
 //Java Program to illustrate the use of multidimensional array class Testarray3{ public static void main(String args[]){ //declaring and initializing 2D array int arr[][]={{1,2,3},{2,4,5},{4,4,5}}; //printing 2D array for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" system.out.print(arr[i][j]+\\' \\'); } system.out.println(); }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 1 2 3 2 4 5 4 4 5 </pre> <h2>Jagged Array in Java</h2> <p>If we are creating odd number of columns in a 2D array, it is known as a jagged array. In other words, it is an array of arrays with different number of columns.</p> <pre> //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\\' \\'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\\' \\'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\\' \\'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;></pre></3;i++){>

Jagged Array Javassa

Jos luomme parittoman määrän sarakkeita 2D-taulukkoon, sitä kutsutaan rosoiseksi taulukoksi. Toisin sanoen se on joukko taulukoita, joissa on eri määrä sarakkeita.

 //Java Program to illustrate the jagged array class TestJaggedArray{ public static void main(String[] args){ //declaring a 2D array with odd columns int arr[][] = new int[3][]; arr[0] = new int[3]; arr[1] = new int[4]; arr[2] = new int[2]; //initializing a jagged array int count = 0; for (int i=0; i <arr.length; i++) for(int j="0;" <arr[i].length; j++) arr[i][j]="count++;" printing the data of a jagged array for (int i="0;" <arr.length; i++){ j++){ system.out.print(arr[i][j]+\\' \\'); } system.out.println(); new line < pre> <span> Test it Now </span> <p>Output:</p> <pre> 0 1 2 3 4 5 6 7 8 </pre> <hr> <h2>What is the class name of Java array?</h2> <p>In Java, an array is an object. For array object, a proxy class is created whose name can be obtained by getClass().getName() method on the object.</p> <pre> //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} </pre> <span> Test it Now </span> <p>Output:</p> <pre> I </pre> <hr> <h2>Copying a Java Array</h2> <p>We can copy an array to another by the arraycopy() method of System class.</p> <p> <strong>Syntax of arraycopy method</strong> </p> <pre> public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) </pre> <h3>Example of Copying an Array in Java</h3> <pre> //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } </pre> <span> Test it Now </span> <p>Output:</p> <pre> caffein </pre> <hr> <h2>Cloning an Array in Java</h2> <p>Since, Java array implements the Cloneable interface, we can create the clone of the Java array. If we create the clone of a single-dimensional array, it creates the deep copy of the Java array. It means, it will copy the actual value. But, if we create the clone of a multidimensional array, it creates the shallow copy of the Java array which means it copies the references.</p> <pre> //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} </pre> <p>Output:</p> <pre> Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false </pre> <h2>Addition of 2 Matrices in Java</h2> <p>Let&apos;s see a simple example that adds two matrices.</p> <pre> //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\\' \\'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\\' \\'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){></pre></arr.length;>

Mikä on Java-taulukon luokan nimi?

Javassa taulukko on objekti. Taulukkoobjektille luodaan välityspalvelinluokka, jonka nimi voidaan saada objektin getClass().getName()-metodilla.

 //Java Program to get the class name of array in Java class Testarray4{ public static void main(String args[]){ //declaration and initialization of array int arr[]={4,4,5}; //getting the class name of Java array Class c=arr.getClass(); String name=c.getName(); //printing the class name of Java array System.out.println(name); }} 
Testaa nyt

Lähtö:

 I 

Java-taulukon kopioiminen

Voimme kopioida taulukon toiseen System-luokan arraycopy()-metodilla.

Arraycopy-menetelmän syntaksi

 public static void arraycopy( Object src, int srcPos,Object dest, int destPos, int length ) 

Esimerkki taulukon kopioimisesta Javassa

 //Java Program to copy a source array into a destination array in Java class TestArrayCopyDemo { public static void main(String[] args) { //declaring a source array char[] copyFrom = { &apos;d&apos;, &apos;e&apos;, &apos;c&apos;, &apos;a&apos;, &apos;f&apos;, &apos;f&apos;, &apos;e&apos;, &apos;i&apos;, &apos;n&apos;, &apos;a&apos;, &apos;t&apos;, &apos;e&apos;, &apos;d&apos; }; //declaring a destination array char[] copyTo = new char[7]; //copying array using System.arraycopy() method System.arraycopy(copyFrom, 2, copyTo, 0, 7); //printing the destination array System.out.println(String.valueOf(copyTo)); } } 
Testaa nyt

Lähtö:

 caffein 

Taulukon kloonaus Javassa

Koska Java-taulukko toteuttaa Cloneable-rajapinnan, voimme luoda Java-taulukon kloonin. Jos luomme yksiulotteisen taulukon kloonin, se luo Java-taulukon syväkopion. Se tarkoittaa, että se kopioi todellisen arvon. Mutta jos luomme moniulotteisen taulukon kloonin, se luo matalan kopion Java-taulukosta, mikä tarkoittaa, että se kopioi viittaukset.

 //Java Program to clone the array class Testarray1{ public static void main(String args[]){ int arr[]={33,3,4,5}; System.out.println(&apos;Printing original array:&apos;); for(int i:arr) System.out.println(i); System.out.println(&apos;Printing clone of the array:&apos;); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println(&apos;Are both equal?&apos;); System.out.println(arr==carr); }} 

Lähtö:

 Printing original array: 33 3 4 5 Printing clone of the array: 33 3 4 5 Are both equal? false 

2 matriisin lisäys Javaan

Katsotaanpa yksinkertainen esimerkki, joka lisää kaksi matriisia.

 //Java Program to demonstrate the addition of two matrices in Java class Testarray5{ public static void main(String args[]){ //creating two matrices int a[][]={{1,3,4},{3,4,5}}; int b[][]={{1,3,4},{3,4,5}}; //creating another matrix to store the sum of two matrices int c[][]=new int[2][3]; //adding and printing addition of 2 matrices for(int i=0;i<2;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="a[i][j]+b[i][j];" system.out.print(c[i][j]+\\' \\'); } system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 2 6 8 6 8 10 </pre> <h2>Multiplication of 2 Matrices in Java</h2> <p>In the case of matrix multiplication, a one-row element of the first matrix is multiplied by all the columns of the second matrix which can be understood by the image given below.</p> <img src="//techcodeview.com/img/java-object-class/39/java-arrays.webp" alt="Matrix Multiplication in Java"> <p>Let&apos;s see a simple example to multiply two matrices of 3 rows and 3 columns.</p> <pre> //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\\' \\'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){></pre></2;i++){>

2 matriisin kertolasku Javassa

Matriisin kertolaskussa ensimmäisen matriisin yksirivinen elementti kerrotaan kaikilla toisen matriisin sarakkeilla, jotka voidaan ymmärtää alla olevan kuvan avulla.

Matriisimultiointi Javassa

Katsotaanpa yksinkertainen esimerkki kahden 3 rivin ja 3 sarakkeen matriisin kertomisesta.

 //Java Program to multiply two matrices public class MatrixMultiplicationExample{ public static void main(String args[]){ //creating two matrices int a[][]={{1,1,1},{2,2,2},{3,3,3}}; int b[][]={{1,1,1},{2,2,2},{3,3,3}}; //creating another matrix to store the multiplication of two matrices int c[][]=new int[3][3]; //3 rows and 3 columns //multiplying and printing multiplication of 2 matrices for(int i=0;i<3;i++){ for(int j="0;j&lt;3;j++){" c[i][j]="0;" k="0;k&lt;3;k++)" { c[i][j]+="a[i][k]*b[k][j];" } end of loop system.out.print(c[i][j]+\\' \\'); printing matrix element system.out.println(); new line }} < pre> <span> Test it Now </span> <p>Output:</p> <pre> 6 6 6 12 12 12 18 18 18 </pre> <h3>Related Topics</h3> <h2> 1) Java Program to copy all elements of one array into another array </h2> <h2> 2) Java Program to find the frequency of each element in the array </h2> <h2> 3) Java Program to left rotate the elements of an array </h2> <h2> 4) Java Program to print the duplicate elements of an array </h2> <h2> 5) Java Program to print the elements of an array </h2> <h2> 6) Java Program to print the elements of an array in reverse order </h2> <h2> 7) Java Program to print the elements of an array present on even position </h2> <h2> 8) Java Program to print the elements of an array present on odd position </h2> <h2> 9) Java Program to print the largest element in an array </h2> <h2> 10) Java Program to print the smallest element in an array </h2> <h2> 11) Java Program to print the number of elements present in an array </h2> <h2> 12) Java Program to print the sum of all the items of the array </h2> <h2> 13) Java Program to right rotate the elements of an array </h2> <h2> 14) Java Program to sort the elements of an array in ascending order </h2> <h2> 15) Java Program to sort the elements of an array in descending order </h2> <h2>16) Find 3rd Largest Number in an Array </h2> <h2>17) Find 2nd Largest Number in an Array </h2> <h2>18) Find Largest Number in an Array </h2> <h2>19) Find 2nd Smallest Number in an Array </h2> <h2>20) Find Smallest Number in an Array </h2> <h2>21) Remove Duplicate Element in an Array </h2> <h2>22) Add Two Matrices </h2> <h2>23) <a href="/java-program-multiply-two-matrices">Multiply Two Matrices</a> </h2> <h2>24) Print Odd and Even Number from an Array </h2> <h2>25) Transpose matrix </h2> <h2> 26) Java Program to subtract the two matrices </h2> <h2> 27) Java Program to determine whether a given matrix is an identity matrix </h2> <h2> 28) Java Program to determine whether a given matrix is a sparse matrix </h2> <h2> 29) Java Program to determine whether two matrices are equal </h2> <h2> 30) Java Program to display the lower triangular matrix </h2> <h2> 31) Java Program to display the upper triangular matrix </h2> <h2> 32) Java Program to find the frequency of odd &amp; even numbers in the given matrix </h2> <h2> 33) Java Program to find the product of two matrices </h2> <h2> 34) Java Program to find the sum of each row and each column of a matrix </h2> <h2> 35) Java Program to find the transpose of a given matrix </h2></3;i++){>

Liittyvät aiheet

1) Java-ohjelma, joka kopioi kaikki taulukon elementit toiseen taulukkoon

2) Java-ohjelma taulukon kunkin elementin taajuuden löytämiseksi

3) Java-ohjelma vasemmalle kiertää taulukon elementtejä

4) Java-ohjelma taulukon päällekkäisten elementtien tulostamiseen

5) Java-ohjelma taulukon elementtien tulostamiseen

6) Java-ohjelma, joka tulostaa taulukon elementit käänteisessä järjestyksessä

7) Java-ohjelma, joka tulostaa tasaisessa paikassa olevan taulukon elementit

8) Java-ohjelma, joka tulostaa parittomassa paikassa olevan taulukon elementit

9) Java-ohjelma, joka tulostaa taulukon suurimman elementin

10) Java-ohjelma, joka tulostaa taulukon pienimmän elementin

11) Java-ohjelma, joka tulostaa taulukossa olevien elementtien määrän

12) Java-ohjelma, joka tulostaa taulukon kaikkien kohteiden summan

13) Java-ohjelma taulukon elementtien oikealle kiertämiseksi

14) Java-ohjelma taulukon elementtien lajittelemiseksi nousevaan järjestykseen

15) Java-ohjelma taulukon elementtien lajitteluun laskevaan järjestykseen

16) Etsi taulukon 3. suurin numero

17) Etsi taulukon toiseksi suurin luku

18) Etsi taulukon suurin luku

19) Etsi taulukon 2. pienin luku

20) Etsi taulukon pienin luku

21) Poista kaksoiselementti taulukosta

22) Lisää kaksi matriisia

23) Kerro kaksi matriisia

24) Tulosta pariton ja parillinen luku taulukosta

25) Transponoi matriisi

26) Java-ohjelma kahden matriisin vähentämiseksi

27) Java-ohjelma sen määrittämiseksi, onko tietty matriisi identiteettimatriisi

28) Java-ohjelma sen määrittämiseksi, onko tietty matriisi harva matriisi

29) Java-ohjelma, joka määrittää, ovatko kaksi matriisia yhtä suuria

30) Java-ohjelma alemman kolmiomatriisin näyttämiseen

31) Java-ohjelma ylemmän kolmiomatriisin näyttämiseen

32) Java-ohjelma parillisten ja parillisten lukujen taajuuden löytämiseksi annetusta matriisista

33) Java-ohjelma kahden matriisin tulon etsimiseen

34) Java-ohjelma matriisin jokaisen rivin ja sarakkeen summan löytämiseksi

35) Java-ohjelma tietyn matriisin transponoinnin löytämiseksi