java版本的escape和unescape函数  

class EscapeUnescape {
    public static String escape(String src) {
    int i;
    char j;
    StringBuffer tmp = new StringBuffer();
    tmp.ensureCapacity(src.length() * 6);
    for (i = 0; i < src.length(); i++) {
        j = src.charAt(i);
        if (Character.isDigit(j) || Character.isLowerCase(j)
            || Character.isUpperCase(j))
        tmp.append(j);
        else if (j < 256) {
        tmp.append("%");
        if (j < 16)
            tmp.append("0");
        tmp.append(Integer.toString(j, 16));
        } else {
        tmp.append("%u");
        tmp.append(Integer.toString(j, 16));
        }
    }
    return tmp.toString();
    }

    public static String unescape(String src) {
    StringBuffer tmp = new StringBuffer();
    tmp.ensureCapacity(src.length());
    int lastPos = 0, pos = 0;
    char ch;
    while (lastPos < src.length()) {
        pos = src.indexOf("%", lastPos);
        if (pos == lastPos) {
        if (src.charAt(pos + 1) == 'u') {
            ch = (char) Integer.parseInt(src
                .substring(pos + 2, pos + 6), 16);
            tmp.append(ch);
            lastPos = pos + 6;
        } else {
            ch = (char) Integer.parseInt(src
                .substring(pos + 1, pos + 3), 16);
            tmp.append(ch);
            lastPos = pos + 3;
        }
        } else {
        if (pos == -1) {
            tmp.append(src.substring(lastPos));
            lastPos = src.length();
        } else {
            tmp.append(src.substring(lastPos, pos));
            lastPos = pos;
        }
        }
    }
    return tmp.toString();
    }

    public static void main(String[] args) {
    String tmp = "~!@#$%^&*()_+|\\=-,./?><;'][{}\"";
    System.out.println("testing escape : " + tmp);
    tmp = escape(tmp);
    System.out.println(tmp);
    System.out.println("testing unescape :" + tmp);
    System.out.println(unescape(tmp));
    }
}