字符串、十六进制、byte数组互转

import java.io.ByteArrayOutputStream;

public class HexUtil {

/**
* @param args
*/
public static void main(String[] args) {

String str = "12345678";

String hexStr = encode(str);

System.out.println("字符串－>十六进制：" + hexStr);

System.out.println("十六进制－>字符串：" + decode(hexStr));

System.out.println("十六进制->byte数组：" + HexString2Bytes(hexStr));

}

public static String stringToHexString(String strPart) {
String hexString = "";
for (int i = 0; i < strPart.length(); i++) {
int ch = (int) strPart.charAt(i);
String strHex = Integer.toHexString(ch);
hexString = hexString + strHex;
}
return hexString;
}

private static String hexString = "0123456789ABCDEF";

/*
* 将字符串编码成16进制数字,适用于所有字符（包括中文）
*/
public static String encode(String str) {
// 根据默认编码获取字节数组
byte[] bytes = str.getBytes();
StringBuilder sb = new StringBuilder(bytes.length * 2);
// 将字节数组中每个字节拆解成2位16进制整数
for (int i = 0; i < bytes.length; i++) {
sb.append(hexString.charAt((bytes[i] & 0xf0) >> 4));
sb.append(hexString.charAt((bytes[i] & 0x0f) >> 0));
}
return sb.toString();
}

/*
* 将16进制数字解码成字符串,适用于所有字符（包括中文）
*/
public static String decode(String bytes) {
ByteArrayOutputStream baos = new ByteArrayOutputStream(
bytes.length() / 2);
// 将每2位16进制整数组装成一个字节
for (int i = 0; i < bytes.length(); i += 2)
baos.write((hexString.indexOf(bytes.charAt(i)) << 4 | hexString
.indexOf(bytes.charAt(i + 1))));
return new String(baos.toByteArray());
}

private static byte uniteBytes(byte src0, byte src1) {
byte _b0 = Byte.decode("0x" + new String(new byte[] { src0 }))
.byteValue();
_b0 = (byte) (_b0 << 4);
byte _b1 = Byte.decode("0x" + new String(new byte[] { src1 }))
.byteValue();
byte ret = (byte) (_b0 | _b1);
return ret;
}

public static byte[] HexString2Bytes(String src) {
byte[] ret = new byte[6];
byte[] tmp = src.getBytes();
for (int i = 0; i < 6; ++i) {
ret[i] = uniteBytes(tmp[i * 2], tmp[i * 2 + 1]);
}
return ret;
}
}