The Arrays class of the java.util package provides toString() methods for all primitive data types and object. These methods accept an array and return its string representation.Therefore, to convert an array to string pass the required array to this method.ExampleLive Demoimport java.util.Arrays; public class ArrayToString {    public static void main(String args[]) throws Exception {       int[] myArray = {23, 93, 56, 92, 39};       String str = Arrays.toString(myArray);       System.out.println(str);    } }Output[23, 93, 56, 92, 39]

Java provides ImageIO class for reading and writing an image. To convert an image to a byte array –Read the image using the read() method of the ImageIO class.Create a ByteArrayOutputStream object.Write the image to the ByteArrayOutputStream object created above using the write() method of the ImageIO class.Finally convert the contents of the ByteArrayOutputStream to a byte array using the toByteArray() method.Exampleimport java.io.ByteArrayOutputStream; import java.awt.image.BufferedImage; import java.io.File; import javax.imageio.ImageIO; public class ImageToByteArray { public static void main(String args[]) throws Exception{ BufferedImage bImage = ImageIO.read(new File("sample.jpg")); ... Read More

To move an element from one position to other (swap) you need to –Create a temp variable and assign the value of the original position to it.Now, assign the value in the new position to original position.Finally, assign the value in the temp to the new position.ExampleLive Demoimport java.util.Arrays; public class ChangingPositions {    public static void main(String args[]) {       int originalPosition = 1;       int newPosition = 1;       int [] myArray = {23, 93, 56, 92, 39};       int temp = myArray[originalPosition];             myArray[originalPosition] = myArray[newPosition];       myArray[newPosition] = temp;       System.out.println(Arrays.toString(myArray));    } }Output[23, 39, 56, 92, 93]

Java provides ImageIO class for reading and writing an image. To convert a byte array to an image.Create a ByteArrayInputStream object by passing the byte array (that is to be converted) to its constructor.Read the image using the read() method of the ImageIO class (by passing the ByteArrayInputStream objects to it as a parameter).Finally, Write the image to using the write() method of the ImageIo class.Exampleimport java.io.ByteArrayOutputStream; import java.awt.image.BufferedImage; import java.io.File; import javax.imageio.ImageIO; public class ByteArrayToImage { public static void main(String args[]) throws Exception { BufferedImage bImage = ImageIO.read(new File("sample.jpg")); ... Read More

You can read data from a PDF file using the read() method of the FileInputStream class this method requires a byte array as a parameter.Exampleimport java.io.File; import java.io.FileInputStream; import java.io.ByteArrayOutputStream; public class PdfToByteArray {    public static void main(String args[]) throws Exception {       File file = new File("sample.pdf");       FileInputStream fis = new FileInputStream(file);       byte [] data = new byte[(int)file.length()];       fis.read(data);       ByteArrayOutputStream bos = new ByteArrayOutputStream();       data = bos.toByteArray();    } }Sample.pdf

Apache Commons provides a library named org.apache.commons.lang3 and, following is the maven dependency to add the library to your project.           org.apache.commons       commons-lang3       3.0     This package provides a class named ArrayUtils. Using the toPrimitive() method of this class you can convert An object array to an array of primitive types:Exampleimport java.util.Arrays; import org.apache.commons.lang3.ArrayUtils; public class ArraysToPrimitives {    public static void main(String args[]) {       Integer[] myArray = {234, 76, 890, 27, 10, 63};       int[] primitiveArray = ArrayUtils.toPrimitive(myArray);       System.out.println(Arrays.toString(primitiveArray));    } }Output[234, 76, 890, 27, 10, 63]

A 2d array is an array of one dimensional arrays to read the contents of a file to a 2d array –Instantiate Scanner or other relevant class to read data from a file. Create an array to store the contents.To copy contents, you need two loops one nested within the other. the outer loop is to traverse through the array of one dimensional arrays and, the inner loop is to traverse through the elements of a particular one dimensional array.Create an outer loop starting from 0 up to the length of the array. Within this loop read each line trim and ... Read More

Using the copyOfRange() method you can copy an array within a range. This method accepts three parameters, an array that you want to copy, start and end indexes of the range.You split an array using this method by copying the array ranging from 0 to length/2 to one array and length/2 to length to other.Exampleimport java.util.Arrays; import java.util.Scanner; public class SplittingAnArray {    public static void main(String args[]) {       Scanner s =new Scanner(System.in);       System.out.println("Enter the required size of the array ::");       int size = s.nextInt();       int [] myArray ... Read More

The interface Set does not allow duplicate elements, therefore, create a set object and try to add each element to it using the add() method in case of repetition of elements this method returns false − If you try to add all the elements of the array to a Set, it accepts only unique elements − Example import java.util.Arrays; import java.util.HashSet; import java.util.Scanner; import java.util.Set; public class CountingUniqueElements { public static void main(String args[]) { Scanner sc = new Scanner(System.in); System.out.println("Enter the size ... Read More

You can find numbers in an array that are greater than, less than, or equal to a value as:ExampleLive Demopublic class GreaterOrLess {    public static void main(String args[]) {       int value = 65;       int[] myArray = {41, 52, 63, 74, 85, 96 };       System.out.println("Elements of the array that are equal to the given value are::");       for(int i = 0; i