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how to iterate hashmap in java

how to iterate hashmap in java 


for explanation watch video::



1)

import java.util.*;

public class Test{  

public static void main(String args[])  {  

HashMap<Integer,String> hm = new HashMap<>();

hm.put(1,"raja");

hm.put(2,"ram");

hm.put(3,"mohan");

hm.put(4,"roy");


for(Map.Entry<Integer,String> e : hm.entrySet()){

System.out.println(e.getKey() + " "+e.getValue());

}

}   

2)

Code:

import java.util.*;

public class Test{  

public static void main(String args[])  {  

HashMap<Integer,String> hm = new HashMap<>();

hm.put(1,"raja");

hm.put(2,"ram");

hm.put(3,"mohan");

hm.put(4,"roy");

//keys

for(int i : hm.keySet()){

System.out.print(i+" ");

}

System.out.println();

for(String s : hm.values()){

System.out.print(s+" ");

}

System.out.println();

}   

3)

import java.util.*;

public class Test{  

public static void main(String args[])  {  

HashMap<Integer,String> hm = new HashMap<>();

hm.put(1,"raja");

hm.put(2,"ram");

hm.put(3,"mohan");

hm.put(4,"roy");

Iterator<Map.Entry<Integer,String>> itr = hm.entrySet().iterator();

while(itr.hasNext()){

System.out.println(itr.next());

}

}   

4)

import java.util.*;

public class Test{  

public static void main(String args[])  {  

HashMap<Integer,String> hm = new HashMap<>();

hm.put(1,"raja");

hm.put(2,"ram");

hm.put(3,"mohan");

hm.put(4,"roy");

hm.forEach((k,v)->System.out.println(k+"="+v));

}   



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