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" ); } } |
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" ); } } |
buffer is ReadOnly buffer
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/Buffer.html#isReadOnly–