how to declare a hashmap in java code example

Example 1: new hashmap java

Map<String, String> myMap = new HashMap<String, String>() {{
        put("a", "b");
        put("c", "d");
    }};

Example 2: declare hashmap java

//remember to first import java.util.*; first

//you can swap out string or integer for other data types
Map<String, Integer> d = new HashMap<>();

Example 3: java hashmap example

//Hash map creation
Map< String,Integer> hm =  
                        new HashMap< String,Integer>(); 
//inserting elements into hashmap
       hm.put("a", new Integer(100)); 
       hm.put("b", new Integer(200)); 
       hm.put("c", new Integer(300)); 
       hm.put("d", new Integer(400));

Example 4: declare a hashmap in java

HashMap<Integer,String> map=new HashMap<Integer,String>();//Creating HashMap