$package("js.lang"); // 沒有包管理時，也可簡單寫成 js = {lang:{}};

js.lang.String = function(){

    this.REGX_HTML_ENCODE = /"|&|'|<|>|[\x00-\x20]|[\x7F-\xFF]|[\u0100-\u2700]/g;

    this.REGX_HTML_DECODE = /&\w+;|&#(\d+);/g;

    this.REGX_TRIM = /(^\s*)|(\s*$)/g;

    this.HTML_DECODE = {
        "<" : "<", 
        ">" : ">", 
        "&" : "&", 
        " ": " ", 
        """: "\"", 
        "©": ""

        // Add more
    };

    this.encodeHtml = function(s){
        s = (s != undefined) ? s : this.toString();
        return (typeof s != "string") ? s :
            s.replace(this.REGX_HTML_ENCODE, 
                      function($0){
                          var c = $0.charCodeAt(0), r = ["&#"];
                          c = (c == 0x20) ? 0xA0 : c;
                          r.push(c); r.push(";");
                          return r.join("");
                      });
    };

    this.decodeHtml = function(s){
        var HTML_DECODE = this.HTML_DECODE;

        s = (s != undefined) ? s : this.toString();
        return (typeof s != "string") ? s :
            s.replace(this.REGX_HTML_DECODE,
                      function($0, $1){
                          var c = HTML_DECODE[$0];
                          if(c == undefined){
                              // Maybe is Entity Number
                              if(!isNaN($1)){
                                  c = String.fromCharCode(($1 == 160) ? 32:$1);
                              }else{
                                  c = $0;
                              }
                          }
                          return c;
                      });
    };

    this.trim = function(s){
        s = (s != undefined) ? s : this.toString();
        return (typeof s != "string") ? s :
            s.replace(this.REGX_TRIM, "");
    };


    this.hashCode = function(){
        var hash = this.__hash__, _char;
        if(hash == undefined || hash == 0){
            hash = 0;
            for (var i = 0, len=this.length; i < len; i++) {
                _char = this.charCodeAt(i);
                hash = 31*hash + _char;
                hash = hash & hash; // Convert to 32bit integer
            }
            hash = hash & 0x7fffffff;
        }
        this.__hash__ = hash;

        return this.__hash__; 
    };

};

js.lang.String.call(js.lang.String);