LongBuffer asReadOnlyBuffer() method in Java

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The asReadOnlyBuffer() method of java.nio.LongBuffer Class is used to create a new, read-only Long buffer with this buffer’s content. The new buffer is a replica of this buffer. Hence changes made to this buffer’s content will be visible in the new buffer.

Since the new buffer is read-only, therefore any modification to its content won’t be allowed. The two buffers’ position, limit, and mark values will be independent. The new buffer’s capacity, limit, position, and mark values will be identical to those of this buffer. If this buffer is itself read-only then this method behaves in exactly the same way as the duplicate method.

Syntax:

public abstract LongBuffer asReadOnlyBuffer()

Return Value: This method returns the new, read-only Long buffer with the same content as that of this buffer.

Below are the examples to illustrate the asReadOnlyBuffer() method:

Examples 1:

// Java program to demonstrate
// asReadOnlyBuffer() 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(8);
            ib.put(2, 9);
            ib.rewind();
  
            // prLong the LongBuffer
            System.out.println("Original LongBuffer:  "
                               + Arrays.toString(ib.array()));
  
            // Creating a read-only copy of LongBuffer
            // using asReadOnlyBuffer() method
            LongBuffer LongBuffer = ib.asReadOnlyBuffer();
  
            // prLong the LongBuffer
            System.out.print("\nReadOnlyBuffer LongBuffer: ");
  
            while (LongBuffer.hasRemaining())
                System.out.print(LongBuffer.get() + ", ");
        }
  
        catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException catched");
        }
  
        catch (ReadOnlyBufferException e) {
            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

Output:

Original LongBuffer:  [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]

ReadOnlyBuffer LongBuffer: 8, 0, 9, 0, 0, 0, 0, 0, 0, 0,

Examples 2:

// Java program to demonstrate
// asReadOnlyBuffer() method
  
import java.nio.*;
import java.util.*;
  
public class GFG {
  
    public static void main(String[] args) throws Exception
    {
  
        // Declaring the capacity of the ib
        int capacity1 = 10;
  
        // Declaring the capacity of the ib1
        int capacity2 = 5;
  
        // Creating the LongBuffer
        try {
            // creating object of Longbuffer ib
            // and allocating size capacity
            LongBuffer ib = LongBuffer.allocate(capacity1);
  
            // putting the value in ib
            ib.put(8);
            ib.put(2, 9);
            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");
        }
  
        catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException catched");
        }
  
        catch (ReadOnlyBufferException e) {
            System.out.println("Exception thrown: " + e);
        }
    }
}

Output:

LongBuffer ib: [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]

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

ReadOnlyBuffer LongBuffer: 8, 0, 9, 0, 0, 0, 0, 0, 0, 0, 

Trying to get the array from ReadOnlyib for editing