ByteBuffer asLongBuffer() method in Java with Examples

The asLongBuffer() method of java.nio.ByteBuffer class is used to create a view of this byte buffer as a long buffer.
The content of the new buffer will start at this buffer’s current position. Changes to this buffer’s content will be visible in the new buffer, and vice versa; the two buffers’ position, limit, and mark values will be independent.
The new buffer’s position will be zero, its capacity and its limit will be the number of bytes remaining in this buffer divided by eight, and its mark will be undefined. The new buffer will be direct if, and only if, this buffer is direct, and it will be read-only if, and only if, this buffer is read-only.
Syntax:

public abstract LongBuffer asLongBuffer()

Return Value: This method returns a new long buffer.
Below are the examples to illustrate the asLongBuffer() method:
Examples 1:

Java

// Java program to demonstrate
// asLongBuffer() method
// for ByteBuffer

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

public class GFG {

    public static void main(String[] args)
    {

        // Declaring the capacity  of the ByteBuffer
        int capacity = 50;

        // Creating the ByteBuffer
        try {

            // creating object of  ByteBuffer
            // and allocating size capacity
            ByteBuffer bb = ByteBuffer.allocate(capacity);

            // changing  bytebuffer into
            // LongBuffer
            LongBuffer lb = bb.asLongBuffer();

            // putting the value in LongBuffer
            lb.put(1000000);
            lb.put(2000000);
            lb.put(3000000);
            lb.put(3000000);
            lb.rewind();

            // Declaring variable c
            long c;

            // print the ByteBuffer
            System.out.print("LongBuffer : ");
            while ((c = lb.get()) != 0)
                System.out.print(c + "  ");
        }

        catch (IllegalArgumentException e) {

            System.out.println("Exception thrown : " + e);
        }

        catch (ReadOnlyBufferException e) {

            System.out.println("Exception thrown : " + e);
        }
    }
}

Output:

LongBuffer : 1000000  2000000  3000000  3000000

Examples 2:

Java

// Java program to demonstrate
// asLongBuffer() method
// for ByteBuffer

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

public class GFG {

    public static void main(String[] args)
    {

        // Declaring the capacity  of the ByteBuffer
        int capacity = 50;

        // Creating the ByteBuffer
        try {

            // creating object of  ByteBuffer
            // and allocating size capacity
            ByteBuffer bb = ByteBuffer.allocate(capacity);

            // changing  bytebuffer into
            // LongBuffer
            LongBuffer lb = bb.asLongBuffer();

            // putting the value in LongBuffer
            lb.put(1000000);
            lb.put(2000000);
            lb.put(3000000);
            lb.rewind();

            // Declaring variable c
            long c;

            // print the ByteBuffer
            System.out.print("LongBuffer : ");
            while ((c = lb.get()) != 0)
                System.out.print(c + "  ");

            // Creating a read-only copy of ByteBuffer
            // using asReadOnlyBuffer() method
            ByteBuffer bb1 = bb.asReadOnlyBuffer();

            // changing read-only bytebuffer into
            // read-only LongBuffer
            LongBuffer lb1 = bb1.asLongBuffer();

            // putting the value in read-only LongBuffer
            System.out.println("\n\nTrying to put the value "
                               + "in read only LongBuffer");
            lb1.put(10);
            lb1.put(20);
            lb1.put(30);
            lb1.rewind();
        }

        catch (IllegalArgumentException e) {

            System.out.println("Exception thrown : " + e);
        }

        catch (ReadOnlyBufferException e) {

            System.out.println("Exception thrown : " + e);
        }
    }
}

Output:

LongBuffer : 1000000  2000000  3000000  

Trying to put the value in read only LongBuffer
Exception thrown : java.nio.ReadOnlyBufferException