The java.nio.CharBuffer is a class we can use to store a buffer of characters. We can use this class’s rewind() method to rewind a buffer. Rewinding a buffer sets the buffer position to zero.
Note:
- The
of the buffer remains unaffected. limit Limit of a buffer is its first index that should not be read or written. - Any position previously marked is discarded.
The CharBuffer.rewind() method is declared as follows:
buff.rewind()
buff: The CharBuffer to rewind.The CharBuffer.rewind() method returns the CharBuffer buff after rewinding.
Consider the code snippet below, which demonstrates the use of the CharBuffer.rewind() method.
import java.nio.*;import java.util.*;public class main {public static void main(String[] args) {int n1 = 4;int n2 = 4;try {CharBuffer buff1 = CharBuffer.allocate(n1);buff1.put('a');buff1.put('c');System.out.println("buff1: " + Arrays.toString(buff1.array()));System.out.println("position at(before rewind): " + buff1.position());System.out.println("rewind()");buff1.rewind();System.out.println("position at(after rewind): " + buff1.position());buff1.put('d');System.out.println("buff1: " + Arrays.toString(buff1.array()));} catch (IllegalArgumentException e) {System.out.println("Error!!! IllegalArgumentException");} catch (ReadOnlyBufferException e) {System.out.println("Error!!! ReadOnlyBufferException");}}}
CharBuffer buff1 is declared in line 8.buff1 using the put() method in line 9-10 . After adding the first element, the position of buff1 is incremented from 0 to 1. After adding the second element, the position of buff1 is incremented from 1 to 2.rewind() method in line 16, the position of buff1 is set to 0. This is why calling the put() method on buff1 adds the element at the 0th index of buff1.Free Resources