javascript实现的HashMap类代码

<script language = "javascript" >

function HashMap() {

    /**Map大小**/

    var size = 0;

    /**对象**/

    var entry = new Object();

    /**Map的存put方法**/

    this.put = function(key, value) {

        if (!this.containsKey(key)) {

            size++;

            entry[key] = value;

        }

    }

    /**Map取get方法**/

    this.get = function(key) {

        return this.containsKey(key) ? entry[key] : null;

    }

    /**Map删除remove方法**/

    this.remove = function(key) {

        if (this.containsKey(key) && (delete entry[key])) {

            size--;

        }

    }

    /**是否包含Key**/

    this.containsKey = function(key) {

        return (key in entry);

    }

    /**是否包含Value**/

    this.containsValue = function(value) {

        for (var prop in entry) {

            if (entry[prop] == value) {

                return true;

            }

        }

        return false;

    }

    /**所有的Value**/

    this.values = function() {

        var values = new Array();

        for (var prop in entry) {

            values.push(entry[prop]);

        }

        return values;

    }

    /**所有的 Key**/

    this.keys = function() {

        var keys = new Array();

        for (var prop in entry) {

            keys.push(prop);

        }

        return keys;

    }

    /**Map size**/

    this.size = function() {

        return size;

    }

    /**清空Map**/

    this.clear = function() {

        size = 0;

        entry = new Object();

    }
}

//创建HashMap对象 

var hashMap = new HashMap();

hashMap.put("A", "1");

hashMap.put("B", "2");

hashMap.put("A", "5");

hashMap.put("C", "3");

hashMap.put("A", "4");

alert(hashMap.size());
</script>