Java中16进制与字符串之间的相互转换

　*字符串转化为Unicode编码:

/**
 * 字符串转换unicode
 */
public static String string2Unicode(String string) {
　　StringBuffer unicode = new StringBuffer();
　　for (int i = 0; i < string.length(); i++) {
　　　　// 取出每一个字符
    char c = string.charAt(i);
    // 转换为unicode
    unicode.append("\u" + Integer.toHexString(c));
　　}
　　return unicode.toString();
}  

*字符串转为16进制

/**
 * 字符串转化成为16进制字符串
 * @param s
 * @return
 */
public static String strTo16(String s) {
    String str = "";
    for (int i = 0; i < s.length(); i++) {
        int ch = (int) s.charAt(i);
        String s4 = Integer.toHexString(ch);
        str = str + s4;
    }
    return str;
}

*16进制转为字符串

/**
 * 16进制转换成为string类型字符串
 * @param s
 * @return
 */
public static String hexStringToString(String s) {
    if (s == null || s.equals("")) {
        return null;
    }
    s = s.replace(" ", "");
    byte[] baKeyword = new byte[s.length() / 2];
    for (int i = 0; i < baKeyword.length; i++) {
        try {
            baKeyword[i] = (byte) (0xff & Integer.parseInt(s.substring(i * 2, i * 2 + 2), 16));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    try {
        s = new String(baKeyword, "UTF-8");
        new String();
    } catch (Exception e1) {
        e1.printStackTrace();
    }
    return s;
}

*Unicode转为字符串

/**
 * unicode 转字符串
 */
public static String unicode2String(String unicode) {
    StringBuffer string = new StringBuffer();
    String[] hex = unicode.split("\\u");
    for (int i = 1; i < hex.length; i++) {
        // 转换出每一个代码点
        int data = Integer.parseInt(hex[i], 16);
        // 追加成string
        string.append((char) data);
    }
    return string.toString();
}

此方法虽然解决了转化过程中中文乱码的问题,但是过于复杂,笔者后来又发现一种新的转化方式,可直接转化,中文不乱码,代码如下:

　　*字符串转16进制

 1 /**
 2  * 字符串转换成为16进制(无需Unicode编码)
 3  * @param str
 4  * @return
 5  */
 6 public static String str2HexStr(String str) {
 7     char[] chars = "0123456789ABCDEF".toCharArray();
 8     StringBuilder sb = new StringBuilder("");
 9     byte[] bs = str.getBytes();
10     int bit;
11     for (int i = 0; i < bs.length; i++) {
12         bit = (bs[i] & 0x0f0) >> 4;
13         sb.append(chars[bit]);
14         bit = bs[i] & 0x0f;
15         sb.append(chars[bit]);
16         // sb.append(' ');
17     }
18     return sb.toString().trim();
19 }

*16进制转为字符串

 1 /**
 2  * 16进制直接转换成为字符串(无需Unicode解码)
 3  * @param hexStr
 4  * @return
 5  */
 6 public static String hexStr2Str(String hexStr) {
 7     String str = "0123456789ABCDEF";
 8     char[] hexs = hexStr.toCharArray();
 9     byte[] bytes = new byte[hexStr.length() / 2];
10     int n;
11     for (int i = 0; i < bytes.length; i++) {
12         n = str.indexOf(hexs[2 * i]) * 16;
13         n += str.indexOf(hexs[2 * i + 1]);
14         bytes[i] = (byte) (n & 0xff);
15     }
16     return new String(bytes);
17 }