lbpmessage.java

中国移动定位引擎的客户端

package ffcs.lbp;

import java.io.UnsupportedEncodingException;
import java.nio.ByteBuffer;
import java.text.SimpleDateFormat;
import java.util.Date;

/*
 * <p>Title: 与收发模块的内部协议解析</p>
 * <p>Description: Lbp内部协议解析基类</p>
 * <p>Copyright: Copyright (c) 2008</p>
 * <p>Company: 福富软件</p>
 * @author chenxin
 * @version 1.0 
 */

public abstract class LbpMessage {

	public static final int MAX_PACKAGE_SIZE = 2048;

	public static final byte ASCII_NULL = (byte) 0;

	private static final String US_ASCII = "US-ASCII";
	
	/**
	 * 消息的总长度
	 * @return
	 */
	public abstract int getPackLength();

	/**
	 *  消息的命令ID
	 * @return
	 */
	public abstract int getCommandId();

	/**
	 * 消息包的序列号
	 * @return
	 */
	public abstract int getSequenceId();
	/**
	 * 把buf消息转换成消息对象
	 * @param buf 字节缓冲区
	 * @return　true　消息解析成功 false　消息解析不成功
	 * @throws ProtocolException　消息解析异常，如消息大小不对，或者消息包的格式错误等
	 */
	public abstract boolean readMsg(ByteBuffer buf) throws ProtocolException;

	/**
	 * 把消息的各字段值写入缓冲区
	 * @param buf 字节缓冲区
	 * @return　true　写入成功 false　写入失败
	 */
	public abstract boolean writeMsg(ByteBuffer buf);

	/**
	 * 从srcBf拷贝字节到destByte中
	 * @param srcBf ByteBuffer 源缓冲区
	 * @param destByte byte[] 目的数组
	 * @param maxLength int  最大长度
	 * @param terminate byte 结束符
	 * @return int
	 */
	public static int copyToByte(ByteBuffer srcBf, byte[] destByte,
			int maxLength, byte terminate) {
		int index = 0;
		if (srcBf == null && srcBf.remaining() < 1) {
			return 0;
		}
		while (srcBf.remaining() > 0) {
			byte b = srcBf.get();
			destByte[index++] = b;
			if (b == terminate || (index >= maxLength)) {
				break;
			}
		}
		return index;
	}

	/**
	 * 检查对象是否为空
	 * @param o
	 * @param name
	 */
	public static void checkNull(Object o, String name) {
		if (o == null) {
			throw new NullPointerException(name);
		}
	}

	/**
	 * 返回消息简单信息
	 * 该方法似toString方法，但比toString方法返回的信息更简要，
	 * 主要用来调试用
	 * @return　返回字符串信息
	 */
	public String getSimpleInfo() {
		return toString();
	}

	/**
	 * 
	 * @param b
	 * @param offset
	 * @return
	 */
	public static String readCString(byte[] b, int offset) {
		String s;
		int p = offset;
		while (b[p] != (byte) 0) {
			p++;
		}
		try {
			if (p > offset) {
				s = new String(b, offset, p - offset, US_ASCII);
			} else {
				s = "";
			}
		} catch (java.io.UnsupportedEncodingException x) {
			s = "";
		}
		return s;
	}

	/**
	 * 对字符串补指定的字符
	 * @param src
	 * @param length
	 * @param c
	 * @return
	 */
	public static String lpad(String src, int length, char c) {
		if (src == null || src.length() >= length) {
			return src;
		}
		String dest = src;
		char[] temp = new char[length - src.length()];
		for (int i = 0; i < length - src.length(); i++) {
			temp[i] = c;
		}

		return (new String(temp) + dest);
	}

	/**
	 * Read a nul-terminated ASCII string from a ByteBuffer.
	 * @param bf
	 * @return
	 */
	public static String readCString(ByteBuffer bf) {
		return readCString(bf, 256);
	}

	/**
	 * Read a nul-terminated ASCII string from a ByteBuffer.
	 * @param bf
	 * @param maxReadLength 最大读取数
	 * @return
	 */
	public static String readCString(ByteBuffer bf, int maxReadLength) {

		if (bf == null && bf.remaining() < 1) {
			return null;
		}
		byte[] data = new byte[maxReadLength];
		int index = 0;
		String s = null;
		while (bf.remaining() > 0) {
			if (index >= maxReadLength) {
				break;
			}
			/*if (index >= maxReadLength) {
				maxReadLength *= 2;
				byte[] temp = new byte[maxReadLength];
				System.arraycopy(data, 0, temp, 0, data.length);
				data = temp;
			}*/
			data[index] = bf.get();
			if (data[index] == ASCII_NULL) {
				break;
			}
			index++;
		}
		try {
			if(index>0){
				s = new String(data, 0, index, US_ASCII);
			}
		} catch (java.io.UnsupportedEncodingException x) {
			x.printStackTrace();
			s = null;
		}
		return s;

	}

	/**
	 * 把写符串以"C-Octet String"方式（以NULL结束的ASCII字符串）写入ByteBuffer
	 * @param bf  要写入的ByteBuffer
	 * @param s　要写入的字符串
	 */
	public static void writeCString(ByteBuffer bf, String s) {
		if (s != null) {
			bf.put(s.getBytes());
		}
		bf.put(ASCII_NULL);
	}

	/**
	 * 把字符串以"Octet String"方式（不强制以0x00 结尾的定长字符串。当位数不足时，
	 在不明确注明的情况下，应左对齐，右补0x00。在
	 明确注明的情况下，以该字段的明确注明为准。）写入ByteBuffer
	 * @param bf  要写入的ByteBuffer
	 * @param s　要写入的字符串
	 */
	public static void writeOString(ByteBuffer bf, String s, int len) {
		if (s == null) {
			bf.put(new byte[len]);
			return;
		}
		int l = s.getBytes().length;
		bf.put(s.getBytes());
		if (l < len) {
			for (int i = 0; i < (len - l); i++)
				bf.put(ASCII_NULL);
		}
	}

	/**
	 * 把字符串以"Octet String"方式（不强制以0x00 结尾的定长字符串。当位数不足时，
	 在不明确注明的情况下，应左对齐，右补0x00。在
	 明确注明的情况下，以该字段的明确注明为准。）写入ByteBuffer
	 * @param bf  要写入的ByteBuffer
	 * @param s　要写入的字符串
	 */
	public static void writeOString(ByteBuffer bf, String s, int len,
			byte msgFormat) {
		String code = "";
		if (msgFormat == (byte) 0)
			code = US_ASCII;
		else if (msgFormat == (byte) 15)
			code = "GBK";
		else if (msgFormat == (byte) 8)
			code = "UTF-16";
		else
			code = "GBK";
		int l = 0;
		try {
			l = s.getBytes(code).length;

			bf.put(s.getBytes(code));
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		if (l < len) {
			for (int i = 0; i < (len - l); i++)
				bf.put(ASCII_NULL);
		}
	}

	/**
	 * 把字符串以"Octet String"方式（不强制以0x00 结尾的定长字符串。当位数不足时，
	 在不明确注明的情况下，应左对齐，右补0x00。在
	 明确注明的情况下，以该字段的明确注明为准。）读出ByteBuffer
	 * @param bf  要写入的ByteBuffer
	 * @param s　要写入的字符串
	 * modi by chenxin 2008.3.14  把循环改成从后往前循环
	 */

	public static String readOString(ByteBuffer bf, int len) {

		String s = null;
		byte[] data = new byte[len];
		bf.get(data);
		int index = data.length;
		for (int i =  data.length-1; i >0; i--) {

			if (data[i] != ASCII_NULL) {
				index = i;
				break;
			}
		}
/*		if (index == data.length)
			index = len;*/
        if(index>0){
        	s = new String(data, 0, index);
        }

		return s;

	}

	/**
	 * 把字符串以"Octet String"方式（不强制以0x00 结尾的定长字符串。当位数不足时，
	 在不明确注明的情况下，应左对齐，右补0x00。在
	 明确注明的情况下，以该字段的明确注明为准。）读出ByteBuffer
	 * @param bf  要写入的ByteBuffer
	 * @param s　要写入的字符串
	 * modi by chenxin 2008.3.14  把循环改成从后往前循环
	 */

	public static String readOString(ByteBuffer bf, int len, byte msgFormat) {

		String s = null;
		byte[] data = new byte[len];
		bf.get(data);
		int index = -1;
		if (msgFormat != (byte) 8)
			for (int i =  data.length-1; i >0; i--) {
				if (data[i] != ASCII_NULL) {
					index = i;
					break;
				}
			}
		else
			index = data.length;
		String code = "";
		if (msgFormat == (byte) 0)
			code = US_ASCII;
		else if (msgFormat == (byte) 15)
			code = "GBK";
		else if (msgFormat == (byte) 8)
			code = "UTF-16";
		else
			code = "GBK";
		try {
			s = new String(data, 0, index, code);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
		return s;
	}

	public String toString() {
		return super.toString();
	}

	/**
	 * Read an ASCII string from a byte array.
	 * @param b The byte array to read from.
	 * @param offset The offset into <code>b</code> to begin reading from.
	 * @param len The length of the string to read.
	 * @return A string decoded from <code>b</code> of length <code>len</code>.
	 * ASCII is used to convert the bytes into characters.
	 */
	public static String readString(byte[] b, int offset, int len) {
		String s = "";
		try {
			if (len > 0) {
				s = new String(b, offset, len, US_ASCII);
			}
		} catch (java.io.UnsupportedEncodingException x) {
		}
		return s;
	}

	public String strToHex(String val) {
		if (val == null)
			return "NULL";
		byte b[] = val.getBytes();
		return byte2hexString(b);

	}

	public static String byte2hexString(byte[] bytes) {
		if (bytes == null) {
			return null;
		}
		StringBuffer buf = new StringBuffer(bytes.length * 2);
		for (int i = 0; i < bytes.length; i++) {
			if (((int) bytes[i] & 0xff) < 0x10) {
				buf.append("0");
			}

			buf.append(Long.toString((int) bytes[i] & 0xff, 16));
			if (i < (bytes.length - 1)) {
				buf.append(' ');
			}
		}
		return buf.toString();
	}

	public static String byte2hexString(ByteBuffer bufer) {
		if (bufer == null) {
			return null;
		}
		StringBuffer buf = new StringBuffer(bufer.remaining() * 2);
		while (bufer.hasRemaining()) {
			byte b = bufer.get();
			if ((((int) b) & 0xff) < 0x10) {
				buf.append("0");
			}

			buf.append(Long.toString((int) b & 0xff, 16));
			if (bufer.remaining() > 0) {
				buf.append(' ');
			}
		}
		return buf.toString();
	}

	public static String byteToHex(byte val) {
		//  if(val==null) return "NULL";
		String stmp = (java.lang.Integer.toHexString(val & 0XFF));
		if (stmp.length() == 1)
			stmp = "0" + stmp;
		return stmp;

	}

	public String intToHex(int val) {

		String s = Integer.toHexString(val);
		String tmp = "";
		for (int i = 8; i > s.length(); i--)
			tmp += "0";
		return tmp + s;

	}

	public static int byteToUnsignInt(byte b) {
		return (0x000000ff & b);
	}

	public static byte intToByte(int i) {
		return ((byte) (0x000000ff & i));
	}

	public static int bytesToInt(byte[] b, int offset, int size) {
		int num = 0;
		int sw = 8 * (size - 1);

		for (int loop = 0; loop < size; loop++) {
			num |= ((int) b[offset + loop] & 0x00ff) << sw;
			sw -= 8;
		}

		return num;
	}
	
	/**
	 * 按指定的时间格式转换系统当前的时间为字符串
	 * @param dateFormat 时间格式
	 * @return 时间字符串
	 */
	public static String dateConvertToStr(String dateFormat){
		return dateConvertToStr(new Date(),dateFormat);
	}
	/**
	 * 把指定的时间根据指定的时间格式，转换为字符串
	 * @param date 时间
	 * @param dateFormat 时间格式
	 * @return 时间字符串
	 */
	public static String dateConvertToStr(Date date,String dateFormat){
		SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
		return sdf.format(date);
	}
	
	/**
	 * 单元测试
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args)throws Exception{
		String s = dateConvertToStr("yyyyMMddHHmmssSSS");
		System.out.println(s);
	}
}