LongBuffer hasArray() method in Java

The array() method of java.nio.LongBuffer Class is used to Return the Long 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 Long[] array()

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

Throws: 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 LongBuffer
        int capacity = 10;

        // Creating the LongBuffer
        try {

            // creating object of Longbuffer
            // and allocating size capacity
            LongBuffer ib = LongBuffer.allocate(capacity);

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

            // getting array from ib LongBuffer using array() method
            long[] ibb = ib.array();

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

        catch (IllegalArgumentException e) {

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

        catch (ReadOnlyBufferException e) {

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

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 LongBuffer
        try {
            //
            // ib
            //
            // creating object of Longbuffer ib
            // and allocating size capacity
            LongBuffer ib = LongBuffer.allocate(capacity1);

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

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

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

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

            // prLong the LongBuffer
            System.out.println("\nLongBuffer ib1:  "
                               + Arrays.toString(ib1.array()));

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

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

            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");

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