源文档 <http://origin100.javaeye.com/blog/267165>
/** |
* 通信格式转换 |
* |
* Java和一些windows编程语言如c、c++、delphi所写的网络程序进行通讯时,需要进行相应的转换 |
* 高、低字节之间的转换 |
* windows的字节序为低字节开头 |
* linux,unix的字节序为高字节开头 |
* java则无论平台变化,都是高字节开头 |
*/ |
public class FormatTransfer { |
/** |
* 将int转为低字节在前,高字节在后的byte数组 |
* @param n int |
* @return byte[] |
*/ |
public static byte[] toLH(int n) { |
byte[] b = new byte[4]; |
b[0] = (byte) (n & 0xff); |
b[1] = (byte) (n >> 8 & 0xff); |
b[2] = (byte) (n >> 16 & 0xff); |
b[3] = (byte) (n >> 24 & 0xff); |
return b; |
} |
/** |
* 将int转为高字节在前,低字节在后的byte数组 |
* @param n int |
* @return byte[] |
*/ |
public static byte[] toHH(int n) { |
byte[] b = new byte[4]; |
b[3] = (byte) (n & 0xff); |
b[2] = (byte) (n >> 8 & 0xff); |
b[1] = (byte) (n >> 16 & 0xff); |
b[0] = (byte) (n >> 24 & 0xff); |
return b; |
} |
/** |
* 将short转为低字节在前,高字节在后的byte数组 |
* @param n short |
* @return byte[] |
*/ |
public static byte[] toLH(short n) { |
byte[] b = new byte[2]; |
b[0] = (byte) (n & 0xff); |
b[1] = (byte) (n >> 8 & 0xff); |
return b; |
} |
/** |
* 将short转为高字节在前,低字节在后的byte数组 |
* @param n short |
* @return byte[] |
*/ |
public static byte[] toHH(short n) { |
byte[] b = new byte[2]; |
b[1] = (byte) (n & 0xff); |
b[0] = (byte) (n >> 8 & 0xff); |
return b; |
} |
/** |
* 将将int转为高字节在前,低字节在后的byte数组 |
public static byte[] toHH(int number) { |
int temp = number; |
byte[] b = new byte[4]; |
for (int i = b.length - 1; i > -1; i--) { |
b = new Integer(temp & 0xff).byteValue(); |
temp = temp >> 8; |
} |
return b; |
} |
public static byte[] IntToByteArray(int i) { |
byte[] abyte0 = new byte[4]; |
abyte0[3] = (byte) (0xff & i); |
abyte0[2] = (byte) ((0xff00 & i) >> 8); |
abyte0[1] = (byte) ((0xff0000 & i) >> 16); |
abyte0[0] = (byte) ((0xff000000 & i) >> 24); |
return abyte0; |
} |
*/ |
/** |
* 将float转为低字节在前,高字节在后的byte数组 |
*/ |
public static byte[] toLH(float f) { |
return toLH(Float.floatToRawIntBits(f)); |
} |
/** |
* 将float转为高字节在前,低字节在后的byte数组 |
*/ |
public static byte[] toHH(float f) { |
return toHH(Float.floatToRawIntBits(f)); |
} |
/** |
* 将String转为byte数组 |
*/ |
public static byte[] stringToBytes(String s, int length) { |
while (s.getBytes().length < length) { |
s += " "; |
} |
return s.getBytes(); |
} |
/** |
* 将字节数组转换为String |
* @param b byte[] |
* @return String |
*/ |
public static String bytesToString(byte[] b) { |
StringBuffer result = new StringBuffer(""); |
int length = b.length; |
for (int i=0; i<length; i++) { |
result.append((char)(b & 0xff)); |
} |
return result.toString(); |
} |
/** |
* 将字符串转换为byte数组 |
* @param s String |
* @return byte[] |
*/ |
public static byte[] stringToBytes(String s) { |
return s.getBytes(); |
} |
/** |
* 将高字节数组转换为int |
* @param b byte[] |
* @return int |
*/ |
public static int hBytesToInt(byte[] b) { |
int s = 0; |
for (int i = 0; i < 3; i++) { |
if (b >= 0) { |
s = s + b; |
} else { |
s = s + 256 + b; |
} |
s = s * 256; |
} |
if (b[3] >= 0) { |
s = s + b[3]; |
} else { |
s = s + 256 + b[3]; |
} |
return s; |
} |
/** |
* 将低字节数组转换为int |
* @param b byte[] |
* @return int |
*/ |
public static int lBytesToInt(byte[] b) { |
int s = 0; |
for (int i = 0; i < 3; i++) { |
if (b[3-i] >= 0) { |
s = s + b[3-i]; |
} else { |
s = s + 256 + b[3-i]; |
} |
s = s * 256; |
} |
if (b[0] >= 0) { |
s = s + b[0]; |
} else { |
s = s + 256 + b[0]; |
} |
return s; |
} |
/** |
* 高字节数组到short的转换 |
* @param b byte[] |
* @return short |
*/ |
public static short hBytesToShort(byte[] b) { |
int s = 0; |
if (b[0] >= 0) { |
s = s + b[0]; |
} else { |
s = s + 256 + b[0]; |
} |
s = s * 256; |
if (b[1] >= 0) { |
s = s + b[1]; |
} else { |
s = s + 256 + b[1]; |
} |
short result = (short)s; |
return result; |
} |
/** |
* 低字节数组到short的转换 |
* @param b byte[] |
* @return short |
*/ |
public static short lBytesToShort(byte[] b) { |
int s = 0; |
if (b[1] >= 0) { |
s = s + b[1]; |
} else { |
s = s + 256 + b[1]; |
} |
s = s * 256; |
if (b[0] >= 0) { |
s = s + b[0]; |
} else { |
s = s + 256 + b[0]; |
} |
short result = (short)s; |
return result; |
} |
/** |
* 高字节数组转换为float |
* @param b byte[] |
* @return float |
*/ |
public static float hBytesToFloat(byte[] b) { |
int i = 0; |
Float F = new Float(0.0); |
i = ((((b[0]&0xff)<<8 | (b[1]&0xff))<<8) | (b[2]&0xff))<<8 | (b[3]&0xff); |
return F.intBitsToFloat(i); |
} |
/** |
* 低字节数组转换为float |
* @param b byte[] |
* @return float |
*/ |
public static float lBytesToFloat(byte[] b) { |
int i = 0; |
Float F = new Float(0.0); |
i = ((((b[3]&0xff)<<8 | (b[2]&0xff))<<8) | (b[1]&0xff))<<8 | (b[0]&0xff); |
return F.intBitsToFloat(i); |
} |
/** |
* 将byte数组中的元素倒序排列 |
*/ |
public static byte[] bytesReverseOrder(byte[] b) { |
int length = b.length; |
byte[] result = new byte[length]; |
for(int i=0; i<length; i++) { |
result[length-i-1] = b; |
} |
return result; |
} |
/** |
* 打印byte数组 |
*/ |
public static void printBytes(byte[] bb) { |
int length = bb.length; |
for (int i=0; i<length; i++) { |
System.out.print(bb + " "); |
} |
System.out.println(""); |
} |
public static void logBytes(byte[] bb) { |
int length = bb.length; |
String out = ""; |
for (int i=0; i<length; i++) { |
out = out + bb + " "; |
} |
} |
/** |
* 将int类型的值转换为字节序颠倒过来对应的int值 |
* @param i int |
* @return int |
*/ |
public static int reverseInt(int i) { |
int result = FormatTransfer.hBytesToInt(FormatTransfer.toLH(i)); |
return result; |
} |
/** |
* 将short类型的值转换为字节序颠倒过来对应的short值 |
* @param s short |
* @return short |
*/ |
public static short reverseShort(short s) { |
short result = FormatTransfer.hBytesToShort(FormatTransfer.toLH(s)); |
return result; |
} |
/** |
* 将float类型的值转换为字节序颠倒过来对应的float值 |
* @param f float |
* @return float |
*/ |
public static float reverseFloat(float f) { |
float result = FormatTransfer.hBytesToFloat(FormatTransfer.toLH(f)); |
return result; |
} |
} |