Hashmap

Home Answers Viewqa Java-Beginners Hashmap

Rahul Dubey

Hashmap
1 Answer(s) 5 months and 25 days ago
Posted in : Java Beginners

public class HashTable {

public static void main(String args[]){

HashMap hm=new HashMap(); hm.put(new Integer(2), "Two"); hm.put(new Integer(1), "One"); hm.put(new Integer(3), "Three"); hm.put(new Integer(4), "Four");

    Set s=hm.entrySet();


    Iterator it=s.iterator();

    while(it.hasNext())
    {

        Map.Entry m =(Map.Entry)it.next();


        m.getKey();


      //  String value=(String)m.getValue();

        System.out.println("The Key is:"+Key+"  The Value is:");//+value);

    }
}

}

i got an error in the "Key" variable..java.lang error please tell me the solution..

View Answers

November 27, 2012 at 1:03 PM

We have modified your code. Here is your code:

import java.util.*;
public class HashTable {

public static void main(String args[]){

HashMap hm=new HashMap(); 
    hm.put(new Integer(2), "Two");
    hm.put(new Integer(1), "One");
    hm.put(new Integer(3), "Three");
    hm.put(new Integer(4), "Four");

    Set s=hm.entrySet();
    Iterator it=s.iterator();
    while(it.hasNext()){
        Map.Entry m =(Map.Entry)it.next();
        System.out.println("The Key is:"+m.getKey()+"  The Value is:"+m.getValue());

    }
}

}

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