Buffer mark() methods in Java with Examples
The mark() method of java.nio.Buffer Class is used to set this buffer’s mark at its position.
Syntax:
public Buffer mark()
Return Value: This method returns this buffer.
Below are the examples to illustrate the mark() method:
Examples 1:
Java
// Java program to demonstrate// mark() methodimport java.nio.*;import java.util.*;public class GFG { public static void main(String[] args) { try { byte[] barr = { 10, 20, 30, 40 }; // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.wrap(barr); // Typecasting ByteBuffer into Buffer Buffer bb1 = (Buffer)bb; // try to set the position at index 2 bb1.position(2); // Set this buffer mark position // using mark() method bb1.mark(); // try to set the position at index 4 bb1.position(4); // display position System.out.println("position before reset: " + bb1.position()); // try to call reset() to restore // to the position we marked bb1.reset(); // display position System.out.println("position after reset: " + bb1.position()); } catch (InvalidMarkException e) { System.out.println("new position is less than " + "the position we marked before "); System.out.println("Exception throws: " + e); } }} |
Output:
position before reset: 4 position after reset: 2
Examples 2: To demonstrate InvalidMarkException
Java
// Java program to demonstrate// mark() methodimport java.nio.*;import java.util.*;public class GFG { public static void main(String[] args) { try { byte[] barr = { 10, 20, 30, 40 }; // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.wrap(barr); // Typecasting ByteBuffer into Buffer Buffer bb1 = (Buffer)bb; // try to set the position at index 2 bb1.position(2); // Set this buffer mark position // using mark() method bb1.mark(); // try to set the position at index 4 bb1.position(1); // display position System.out.println("position before reset: " + bb1.position()); // try to call reset() to restore // to the position we marked bb1.reset(); // display position System.out.println("position after reset: " + bb1.position()); } catch (InvalidMarkException e) { System.out.println("\new position is less than " + "the position we marked before "); System.out.println("Exception throws: " + e); } }} |
Output:
position before reset: 1 new position is less than the position we marked before Exception throws: java.nio.InvalidMarkException
Reference: https://docs.oracle.com/javase/9/docs/api/java/nio/Buffer.html#mark–
