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.
Edut
Haitat
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'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'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'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 'main' 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'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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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'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'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 'main' 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'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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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 'main' 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'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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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 'main' 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'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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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 'main' 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'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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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<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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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'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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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 = { 'd', 'e', 'c', 'a', 'f', 'f', 'e', 'i', 'n', 'a', 't', 'e', 'd' }; //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('Printing original array:'); for(int i:arr) System.out.println(i); System.out.println('Printing clone of the array:'); int carr[]=arr.clone(); for(int i:carr) System.out.println(i); System.out.println('Are both equal?'); 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<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'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<3;j++){" c[i][j]="0;" k="0;k<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 & 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.
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<3;j++){" c[i][j]="0;" k="0;k<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 & 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++){>