Buffer rewind() methods in Java with Examples
Last Updated :
23 Jul, 2019
The rewind() method of java.nio.ByteBuffer Class is used to rewind this buffer. The position is set to zero and the mark is discarded. Invoke this method before a sequence of channel-write or get operations, assuming that the limit has already been set appropriately. Invoking this method neither changes nor discards the mark’s value.
Syntax:
public ByteBuffer rewind()
Return Value: This method returns this buffer.
Below are the examples to illustrate the rewind() method:
Examples 1:
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
ByteBuffer byteBuffer
= ByteBuffer.allocate( 4 );
byteBuffer.put(( byte ) 20 );
byteBuffer.put(( byte ) 'a' );
Buffer buffer = (Buffer)byteBuffer;
System.out.println( "Buffer before operation: "
+ Arrays.toString(
( byte [])buffer.array())
+ "\nPosition: "
+ buffer.position()
+ "\nLimit: "
+ buffer.limit());
buffer.rewind();
System.out.println( "\nBuffer after operation: "
+ Arrays.toString(
( byte [])buffer.array())
+ "\nPosition: "
+ buffer.position()
+ "\nLimit: "
+ buffer.limit());
}
}
|
Output:
Buffer before operation: [20, 97, 0, 0]
Position: 2
Limit: 4
Buffer after operation: [20, 97, 0, 0]
Position: 0
Limit: 4
Examples 2:
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
ByteBuffer byteBuffer
= ByteBuffer.allocate( 5 );
byteBuffer.put(( byte ) 20 );
byteBuffer.put(( byte ) 30 );
byteBuffer.put(( byte ) 40 );
byteBuffer.mark();
Buffer buffer = (Buffer)byteBuffer;
System.out.println( "Buffer before operation: "
+ Arrays.toString(
( byte [])buffer.array())
+ "\nPosition: "
+ buffer.position()
+ "\nLimit: "
+ buffer.limit());
buffer.rewind();
System.out.println( "\nBuffer after operation: "
+ Arrays.toString(
( byte [])buffer.array())
+ "\nPosition: "
+ buffer.position()
+ "\nLimit: "
+ buffer.limit());
}
}
|
Output:
Buffer before operation: [20, 30, 40, 0, 0]
Position: 3
Limit: 5
Buffer after operation: [20, 30, 40, 0, 0]
Position: 0
Limit: 5
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/Buffer.html#rewind–
Like Article
Suggest improvement
Share your thoughts in the comments
Please Login to comment...