Javascript implementation of a simple Map example

  • 2020-03-30 01:02:28
  • OfStack

 
 
function Map() { 
this.elements = new Array(); 

//Gets the number of MAP elements
this.size = function() { 
return this.elements.length; 
}; 

//Determines if the MAP is empty
this.isEmpty = function() { 
return (this.elements.length < 1); 
}; 

//Delete all elements of the MAP
this.clear = function() { 
this.elements = new Array(); 
}; 

//Add an element (key, value) to the MAP
this.put = function(_key, _value) { 
this.elements.push( { 
key : _key, 
value : _value 
}); 
}; 

//Deletes the element that specifies the KEY, returns True on success, False on failure
this.removeByKey = function(_key) { 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].key == _key) { 
this.elements.splice(i, 1); 
return true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Deletes the element with the specified VALUE, returns True on success, False on failure
this.removeByValue = function(_value) {//removeByValueAndKey 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].value == _value) { 
this.elements.splice(i, 1); 
return true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Deletes the element with the specified VALUE, returns True on success, False on failure
this.removeByValueAndKey = function(_key,_value) { 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].value == _value && this.elements[i].key == _key) { 
this.elements.splice(i, 1); 
return true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Gets the element VALUE of the specified KEY. NULL is returned
this.get = function(_key) { 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].key == _key) { 
return this.elements[i].value; 
} 
} 
} catch (e) { 
return false; 
} 
return false; 
}; 

//Gets the element of the specified index (element.key, element.value gets key and value), fails to return NULL
this.element = function(_index) { 
if (_index < 0 || _index >= this.elements.length) { 
return null; 
} 
return this.elements[_index]; 
}; 

//Determines whether the MAP contains an element with the specified KEY
this.containsKey = function(_key) { 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].key == _key) { 
bln = true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Determines whether the MAP contains an element with the specified VALUE
this.containsValue = function(_value) { 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].value == _value) { 
bln = true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Determines whether the MAP contains an element with the specified VALUE
this.containsObj = function(_key,_value) { 
var bln = false; 
try { 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].value == _value && this.elements[i].key == _key) { 
bln = true; 
} 
} 
} catch (e) { 
bln = false; 
} 
return bln; 
}; 

//Get an ARRAY of all values in the MAP
this.values = function() { 
var arr = new Array(); 
for (i = 0; i < this.elements.length; i++) { 
arr.push(this.elements[i].value); 
} 
return arr; 
}; 

//Get an ARRAY of all values in the MAP
this.valuesByKey = function(_key) { 
var arr = new Array(); 
for (i = 0; i < this.elements.length; i++) { 
if (this.elements[i].key == _key) { 
arr.push(this.elements[i].value); 
} 
} 
return arr; 
}; 

//Get an ARRAY of all the keys in the MAP
this.keys = function() { 
var arr = new Array(); 
for (i = 0; i < this.elements.length; i++) { 
arr.push(this.elements[i].key); 
} 
return arr; 
}; 

//Get key through value
this.keysByValue = function(_value) { 
var arr = new Array(); 
for (i = 0; i < this.elements.length; i++) { 
if(_value == this.elements[i].value){ 
arr.push(this.elements[i].key); 
} 
} 
return arr; 
}; 

//Get an ARRAY of all the keys in the MAP
this.keysRemoveDuplicate = function() { 
var arr = new Array(); 
for (i = 0; i < this.elements.length; i++) { 
var flag = true; 
for(var j=0;j<arr.length;j++){ 
if(arr[j] == this.elements[i].key){ 
flag = false; 
break; 
} 
} 
if(flag){ 
arr.push(this.elements[i].key); 
} 
} 
return arr; 
}; 
} 

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