HashMap - Documentation

Constructor

new HashMap()

Author:

ljsoo0925@gmail.com

Example

var hm = new HashMap ();

Methods

(static) clear()

This method is used to remove all of th mappings from this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);  
hm.put("B", 2); 
hm.clear();

(static) containsKey(key) → {Boolean}

This method is used to check if this hash map contains the specified key.

Example

var hm = new HashMap ();
var ret1 = hm.containsKey("A"); // ret1 = false
hm.put("A", 1);  
var ret2 = hm.containsKey("A"); // ret1 = true

Parameters:

Name	Type	Description
`key`	undefined	The key with which the specified value is to be associated.

Throws:

This method returns 'false' if the parameter is missing.

Returns:

This method returns ‘true’ if this hash map contains the specified key, or ‘false’ if this hash map doesn’t contain the specified key.

Type: Boolean

(static) containsValue(value) → {Boolean}

This method is used to check if this hash map contains the specified value.

Example

var hm = new HashMap ();
var ret1 = hm.containsValue(1); // ret1 = false
hm.put("A", 1);  
var ret2 = hm.containsValue(1); // ret1 = true

Parameters:

Name	Type	Description
`value`	undefined	The value with which the specified key is to be associated.

Throws:

This method returns 'false' if the parameter is missing.

Returns:

This method returns ‘true’ if this hash map contains the specified value, or ‘false’ if this hash map doesn’t contain the specified value.

Type: Boolean

(static) entrySet() → {Set}

This method is used to get a Set of the mappings in this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);  
hm.put("B", 2); 
hm.put("가", 2);
Set set = hm.keySet(); // set = {"A-1", "B-2", "가-2"}

Returns:

This method returns a set of the mappings in this hash map.

Type: Set

(static) get(key) → {undefined}

This method is used to get the value which mapped with the specified key from this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1) ;
var ret = hm.get("A"); // ret1 = 1

Parameters:

Name	Type	Description
`key`	undefined	the key with which the specified value is to be associated.

Throws:

This method return false if the parameter is missing, or null if this hash map doesn’t contain this key.

Returns:

This method returns the value which be associated with the specified key.

Type: undefined

(static) isEmpty() → {Boolean}

This method is used to check if this hash map is empty.

Example

var hm = new HashMap ();
var ret1 = hm.isEmpty(); // ret1 = true;
hm.put("A", 1);  
hm.put("B", 2); 
var ret2 = hm.isEmpty(); // ret2 = false

Returns:

The method returns ‘true’ if this deque is empty, or ‘false’ if this deque is not empty.

Type: Boolean

(static) keySet() → {Set}

This method is used to get a Set of the keys in this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);  
hm.put("B", 2); 
hm.put("가", 2);
Set set = hm.keySet(); // set = {"A", "B", "가"}

Returns:

This method returns a set of the key in this hash map.

Type: Set

(static) put(key, value)

This method is used to insert the specified key with the specified value in this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);   // (key : A) - (Value : 1)
hm.put("가", 1);  // (key : 가) - (Value : 1)
hm.put("A", 2);   // (key : A) - (Value : 2) => change value associated with key A

Parameters:

Name	Type	Description
`key`	undefined	The key with which the specified value is to be associated.
`value`	undefined	The value to be associated with the specified key.

Throws:

This method returns 'false' if the either one parameter is missing.

(static) remove(key)

This method is used to remove the mapping with the specified key from this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);  
hm.put("B", 2); 
hm.remove("A"); // (key : A) - (Value : 1) will be removed

Parameters:

Name	Type	Description
`key`	undefined	the key with which the specified value is to be associated.

Throws:

This method returns 'false' if the parameter is missing, or null if this hash map doesn’t contain this key.

(static) size() → {Number}

This method is used to get the number of key-value mappings in this hash map.

Example

var hm = new HashMap ();
hm.put("A", 1);  
hm.put("B", 2); 
var size = hm.size(); // size = 2

Returns:

The method returns the number of values in this deque.

Type: Number