Java ByteBuffer demo

BufferTest.java

import java.nio.ByteBuffer;

public class BufferTest {
  private ByteBuffer buffer;

  public BufferTest(){
    buffer = ByteBuffer.allocate(20);
  }

  public void runTest(){
    System.out.println("Running test");


    System.out.println("\nWrite 5 characters, flip, read until they are consumed (5 characters), then compact");
    dumpBuffer(buffer.duplicate());

    buffer.put("hello".getBytes());
    System.out.println("Put \"hello\"");
    dumpBuffer(buffer.duplicate());

    buffer.flip();
    System.out.println("Flipped");
    dumpBuffer(buffer.duplicate());

    while(buffer.hasRemaining()){
    System.out.print( ((char)buffer.get()) + " " );

    }
    System.out.println();
    dumpBuffer(buffer.duplicate());

    buffer.compact();
    System.out.println("Compacted");
    dumpBuffer(buffer.duplicate());





    System.out.println("\nWrite 20 characters, flip, read 5 characters, then compact");
    buffer.put("11111222223333344444".getBytes());
    System.out.println("Put \"11111222223333344444\"");
    dumpBuffer(buffer.duplicate());

    buffer.flip();
    System.out.println("Flipped");
    dumpBuffer(buffer.duplicate());
    int i = 0;
    while(i++ < 5 && buffer.hasRemaining()){
    System.out.print(((char)buffer.get()) +" " );

    }
    System.out.println();
    dumpBuffer(buffer.duplicate());

    buffer.compact();
    System.out.println("Compacted");
    dumpBuffer(buffer.duplicate());


    System.out.println("\nWrite 5 characters, flip, read until they are consumed (20 characters), then compact");

    buffer.put("55555".getBytes());
    System.out.println("Put \"55555\"");
    dumpBuffer(buffer.duplicate());

    buffer.flip();
    System.out.println("Flipped");
    dumpBuffer(buffer.duplicate());

    while(buffer.hasRemaining()){
    System.out.print(((char)buffer.get()) +" " );

    }
    System.out.println();
    dumpBuffer(buffer.duplicate());

    buffer.compact();
    System.out.println("Compacted");
    dumpBuffer(buffer.duplicate());

    System.out.println("Done running test");
  }


  private void dumpBuffer(ByteBuffer b){
    System.out.println("position: " + b.position() +" limit:" + b.limit() + " has more:" + b.hasRemaining() );
  }

  public static void main(String[] args){
    BufferTest test = new BufferTest();
    test.runTest();
  }
}