IntBuffer array() method in Java

The array() method of java.nio.IntBuffer Class is used to Return the int array that backs this buffer. Modifications to this buffer’s content will cause the returned array’s content to be modified, and vice versa. Invoke() the hasArray() method are used before invoking this method in order to ensure that this buffer has an accessible backing array

Syntax:

public final int[] array()

Return Value: This method returns the array that backs this buffer.

Exception: This method throws the ReadOnlyBufferException(If this buffer is backed by an array but is read-only)

Below program illustrates the array() method:

Examples 1:

// Java program to demonstrate
// array() method

import java.nio.*;
import java.util.*;

public class GFG {
    public static void main(String[] args)
    {

        // Declaring the capacity of the IntBuffer
        int capacity = 10;

        // Creating the IntBuffer
        try {

            // creating object of Intbuffer
            // and allocating size capacity
            IntBuffer ib = IntBuffer.allocate(capacity);

            // putting the value in Intbuffer
            ib.put(7);
            ib.put(2, 6);
            ib.rewind();

            // getting array from ib IntBuffer using array() method
            int[] ibb = ib.array();

            // printing the IntBuffer ib
            System.out.println("IntBuffer:  "
                               + Arrays.toString(ibb));
        }

        catch (IllegalArgumentException e) {

            System.out.println("IllegalArgumentException catched");
        }

        catch (ReadOnlyBufferException e) {

            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

Output:

IntBuffer:  [7, 0, 6, 0, 0, 0, 0, 0, 0, 0]

Examples 2:

// Java program to demonstrate
// array() method

import java.nio.*;
import java.util.*;

public class GFG {
    public static void main(String[] args)
    {

        // Declaring the capacity of the ib
        int capacity1 = 10;

        // Declaring the capacity of the ib1
        int capacity2 = 5;

        // Creating the IntBuffer
        try {
            //
            // ib
            //
            // creating object of Intbuffer ib
            // and allocating size capacity
            IntBuffer ib = IntBuffer.allocate(capacity1);

            // putting the value in ib
            ib.put(7);
            ib.put(2, 6);
            ib.put(3, 7);
            ib.rewind();

            // print the IntBuffer
            System.out.println("IntBuffer ib: "
                               + Arrays.toString(ib.array()));

            //
            // ib1
            //
            // creating object of Intbuffer ib1
            // and allocating size capacity
            IntBuffer ib1 = IntBuffer.allocate(capacity2);

            // putting the value in ib1
            ib1.put(1, 4);
            ib1.put(2, 6);
            ib1.rewind();

            // print the IntBuffer
            System.out.println("\nIntBuffer ib1:  "
                               + Arrays.toString(ib1.array()));

            // Creating a read-only copy of IntBuffer
            // using asReadOnlyBuffer() method
            IntBuffer readOnlyib = ib.asReadOnlyBuffer();

            // print the IntBuffer
            System.out.print("\nReadOnlyBuffer IntBuffer: ");

            while (readOnlyib.hasRemaining())
                System.out.print(readOnlyib.get() + ", ");

            // try to change readOnlyib
            System.out.println("\n\nTrying to get the array"
                               + " from ReadOnlyib for editing");

            int[] ibarr = readOnlyib.array();
        }
        catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException catched");
        }
        catch (ReadOnlyBufferException e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

Output:

IntBuffer ib: [7, 0, 6, 7, 0, 0, 0, 0, 0, 0]

IntBuffer ib1:  [0, 4, 6, 0, 0]

ReadOnlyBuffer IntBuffer: 7, 0, 6, 7, 0, 0, 0, 0, 0, 0, 

Trying to get the array from ReadOnlyib for editing
Exception thrown: java.nio.ReadOnlyBufferException