The isReadOnly() method of java.nio.Buffer class is used to tell whether or not this buffer is read-only.
Syntax:
public abstract boolean isReadOnly()
Returns: This method will return true if, and only if, this buffer is read-only.
Below are the examples to illustrate the isReadOnly() method:
Examples 1:
// Java program to demonstrate// isReadOnly() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 10; // creating object of bytebuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the value in bytebuffer bb.put((byte)10); bb.put((byte)20); bb.rewind(); // Typecast bytebuffer to Buffer Buffer buffer = (Buffer)bb; // checking buffer is backed by array or not boolean isReadOnly = buffer.isReadOnly(); // checking if else condition if (isReadOnly) System.out.println("buffer is" + " ReadOnly buffer"); else System.out.println("buffer is not" + " ReadOnly buffer"); }} |
Output:
buffer is not ReadOnly buffer
Examples 2:
// Java program to demonstrate// isReadOnly() method import java.nio.*;import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 10; // creating object of bytebuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the value in bytebuffer bb.put((byte)10); bb.put((byte)20); bb.rewind(); // Creating a read-only copy of ByteBuffer // using asReadOnlyBuffer() method ByteBuffer bb1 = bb.asReadOnlyBuffer(); // Typecast read-only ByteBuffer to read-only buffer Buffer buffer = (Buffer)bb1; // checking buffer is backed by array or not boolean isReadOnly = buffer.isReadOnly(); // checking if else condition if (isReadOnly) System.out.println("buffer is" + " ReadOnly buffer"); else System.out.println("buffer is not" + " ReadOnly buffer"); }} |
Output:
buffer is ReadOnly buffer
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/Buffer.html#isReadOnly–