Java ByteBuffer copy to another ByteBuffer

import java.nio.ByteBuffer;

public class Main {
  public static void main(String[] argv) {
    ByteBuffer b = ByteBuffer.wrap("demo2s.com".getBytes());
    ByteBuffer c = ByteBuffer.allocate(30);
    copy(b, c);//from   w w w. jav  a 2s. co m
    System.out.println(b);
    System.out.println(c);
  }

  public final static int copy(final ByteBuffer from, final ByteBuffer to) {
    final int len = from.limit();
    return copy(from, 0, to, 0, len);
  }

  public final static int copy(final ByteBuffer from, final int offset1, final ByteBuffer to, final int offset2,
      final int len) {
    System.arraycopy(from.array(), offset1, to.array(), offset2, len);
    to.limit(offset2 + len);
    return len;
  }
}

import java.nio.ByteBuffer;
import java.nio.ByteOrder;

public class Main {
  public static void main(String[] argv) {
    ByteBuffer b = ByteBuffer.wrap("demo2s.com".getBytes());
    ByteBuffer c = copyByteBuffer(b);
    System.out.println(b);/*from   w ww. j a  v  a  2s.co m*/
    System.out.println(c);
  }
    public static ByteBuffer copyByteBuffer(ByteBuffer paramByteBuffer) {
        ByteBuffer localByteBuffer = newByteBuffer(paramByteBuffer
                .remaining());
        paramByteBuffer.mark();
        localByteBuffer.put(paramByteBuffer);
        paramByteBuffer.reset();
        localByteBuffer.rewind();
        return localByteBuffer;
    }

    public static ByteBuffer newByteBuffer(int paramInt) {
        ByteBuffer localByteBuffer = ByteBuffer.allocateDirect(paramInt);
        localByteBuffer.order(ByteOrder.nativeOrder());
        return localByteBuffer;
    }
}

import java.nio.ByteBuffer;

public class Main {
  public static void main(String[] argv) {
    ByteBuffer b = ByteBuffer.wrap("demo2s.com".getBytes());
    ByteBuffer c = copyByteBuffer(b);
    System.out.println(b);//from   w  w  w  . j  a  v  a2s .  c  o m
    System.out.println(c);
  }

  public static java.nio.ByteBuffer copyByteBuffer(java.nio.ByteBuffer data) {
    if (data == null) {
      return null;
    }
    java.nio.ByteBuffer buf = createDirectByteBuffer(convertByteBufferToArray(data));
    return buf;
  }

  public static java.nio.ByteBuffer createDirectByteBuffer(byte[] data) {
    if (data == null) {
      return null;
    }
    java.nio.ByteBuffer buf = java.nio.ByteBuffer.allocateDirect((Byte.SIZE / 8) * data.length)
        .order(java.nio.ByteOrder.nativeOrder());
    buf.clear();
    buf.put(data);
    buf.flip();
    return buf;
  }

  public static byte[] convertByteBufferToArray(java.nio.ByteBuffer buf) {
    if (buf.hasArray()) {
      return buf.array();
    } else {
      buf.rewind();
      byte[] array = new byte[buf.remaining()];
      int index = 0;
      while (buf.hasRemaining()) {
        array[index++] = buf.get();
      }
      return array;
    }
  }
}