[ZZ]byte[]到short、int、long的相互转换

public final static byte[] getBytes(short s, boolean asc) 
{
	byte[] buf = new byte[2];
	if (asc)
		for (int i = buf.length - 1; i >= 0; i--) 
		{
			buf[i] = (byte) (s & 0x00ff);
		  s >>= 8;
		}
	else
		for (int i = 0; i < buf.length; i++) 
		{
			buf[i] = (byte) (s & 0x00ff);
		  s >>= 8;
		}
	return buf;
}

public final static byte[] getBytes(int s, boolean asc) 
{
	byte[] buf = new byte[4];
	if (asc)
	  for (int i = buf.length - 1; i >= 0; i--) 
	  {
	    buf[i] = (byte) (s & 0x000000ff);
	    s >>= 8;
	  }
	else
	  for (int i = 0; i < buf.length; i++)
	  {
	    buf[i] = (byte) (s & 0x000000ff);
	    s >>= 8;
	  }
	return buf;
}

public final static byte[] getBytes(long s, boolean asc) 
{
	byte[] buf = new byte[8];
	if (asc)
	  for (int i = buf.length - 1; i >= 0; i--) 
		{
	    buf[i] = (byte) (s & 0x00000000000000ff);
	    s >>= 8;
	  }
	else
	  for (int i = 0; i < buf.length; i++) 
		{
	    buf[i] = (byte) (s & 0x00000000000000ff);
	    s >>= 8;
	  }
	return buf;
}

public final static short getShort(byte[] buf, boolean asc) 
{
	if (buf == null) 
	{
	  throw new IllegalArgumentException("byte array is null!");
	}
	if (buf.length > 2) 
	{
	  throw new IllegalArgumentException("byte array size > 2 !");
	}
	short r = 0;
	if (asc)
	  for (int i = buf.length - 1; i >= 0; i--) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x00ff);
	  }
	else
	  for (int i = 0; i < buf.length; i++) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x00ff);
	  }
	return r;
}

public final static int getInt(byte[] buf, boolean asc) 
{
	if (buf == null) 
	{
	  throw new IllegalArgumentException("byte array is null!");
	}
	if (buf.length > 4) 
	{
	  throw new IllegalArgumentException("byte array size > 4 !");
	}
	int r = 0;
	if (asc)
	  for (int i = buf.length - 1; i >= 0; i--) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x000000ff);
	  }
	else
	  for (int i = 0; i < buf.length; i++) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x000000ff);
	  }
	return r;
}

public final static long getLong(byte[] buf, boolean asc) 
{
	if (buf == null) 
	{
	  throw new IllegalArgumentException("byte array is null!");
	}
	if (buf.length > 8) 
	{
	  throw new IllegalArgumentException("byte array size > 8 !");
	}
	long r = 0;
	if (asc)
	  for (int i = buf.length - 1; i >= 0; i--) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x00000000000000ff);
	  }
	else
	  for (int i = 0; i < buf.length; i++) 
		{
	    r <<= 8;
	    r |= (buf[i] & 0x00000000000000ff);
	  }
	return r;
}

posted on 2010-10-08 15:12  浩然119  阅读(6349)  评论(0编辑  收藏  举报