Java Map forEach

We can also initialize the map using the double-brace syntax: Map<String, String> doubleBraceMap = new HashMap<String, String>() {{ put(“key1”, “value1”); put(“key2”, “value2”); }};

Generally if there is no collision in the hashing value of the key then the complexity of the the containskey is O(1) . The complexity can be understood by seeing how the method has been implemented. The Hashmap contains array of nodes.

Create an iterator to iterate over the HashMap using HashMap. iterate() method.

Create an iterator to iterate over the HashMap using HashMap. iterate() method.

We can also initialize the map using the double-brace syntax: Map<String, String> doubleBraceMap = new HashMap<String, String>() {{ put(“key1”, “value1”); put(“key2”, “value2”); }};