Create HashMap.java

Author: prashantkumar-cmd

HashMap.java

@@ -0,0 +1,30 @@
+package hashing;
+
+import java.util.*;  
+class HashMap{  
+ public static void main(String args[]){  
+   HashMap<Integer,String> hm=new HashMap<Integer,String>();    
+    System.out.println("Initial list of elements: "+hm);  
+      hm.put(100,"Amit");    
+      hm.put(101,"Vijay");    
+      hm.put(102,"Rahul");   
+       
+      System.out.println("After invoking put() method ");  
+      for(Map.Entry m:hm.entrySet()){    
+       System.out.println(m.getKey()+" "+m.getValue());    
+      }  
+        
+      hm.putIfAbsent(103, "Gaurav");  
+      System.out.println("After invoking putIfAbsent() method ");  
+      for(Map.Entry m:hm.entrySet()){    
+           System.out.println(m.getKey()+" "+m.getValue());    
+          }  
+      HashMap<Integer,String> map=new HashMap<Integer,String>();  // another object map
+      map.put(104,"Ravi");  
+      map.putAll(hm);  
+      System.out.println("After invoking putAll() method ");  
+      for(Map.Entry m:map.entrySet()){    
+           System.out.println(m.getKey()+" "+m.getValue());    
+          }  
+ }  
+}