Java hashmap question

Question

1.00/5 (1 vote)

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I have the code

Java

import java.util.*;

class factory{
    int a;
    int b;
    public factory(int a,int b){
        this.a = a;
        this.b = b;

    }

    public int getA() {
        return a;
    }

    public int getB() {
        return b;
    }
    
}
public class JavaApplication2 {

    public static void main(String[] args) {

        Map<Integer,factory> base = new HashMap<>();
        Scanner in;
        in = new Scanner(System.in);
        int entityCount = in.nextInt();
            for (int i = 0; i < entityCount; i++) {
                int entityId = in.nextInt();
                int arg1 = in.nextInt();

                base.put(entityId, new factory(entityId,arg1));
            }
            base.values().forEach((factory _item) -> {
                HERE if
        });
    }
    
}

i add the value for exemple
2
1 2
3 4
how do i check the value from the entityId 0 value a(which is 1) with the entityid 1 value b(which is 4).

on this phot you will find more specific what i want to compare
http://oi66.tinypic.com/j7enar.jpg

What I have tried:

i have try

Java

base.values().iterator()

but i get

java.util.HashMap$ValueIterator@e9e54c2
java.util.HashMap$ValueIterator@65ab7765

Posted 1-Mar-17 14:22pm

soulbog

Updated 9-Jun-19 22:17pm

v3

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Comments

Richard MacCutchan 2-Mar-17 3:22am

You need to extract each factory object and compare them against each other. The forEach construct may not be the best choice of operation.

soulbog 2-Mar-17 4:54am

yes but how? that i dont know

Richard MacCutchan 2-Mar-17 5:39am

Probably better to use an iterator as described in HashMap in Java with Example[^].

soulbog 2-Mar-17 5:47am

if use that i need to make a entry and iterator. i posted a shorter solution in answear..

2 solutions

Solution 2

Hello, to completely understand how Map and its methods work you can check this example
Java Map Example

Posted 9-Jun-19 22:17pm

Member 14491029

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soulbog · Accepted Answer · 2017-03-01T23:32:00

Solution 1

found 2 solution now..

Java

base.values().forEach((factory _item) -> {
                System.out.println(_item.getA()+ " " _item.getB());
               
        });

and the second one is

Java

for (factory t1:base.values()){
              System.out.println(t1.getA() + ", " + t1.getB());
          }

if somoane knows a better one pls let me know

Posted 1-Mar-17 23:32pm

soulbog

Updated 1-Mar-17 23:46pm

Comments

Richard MacCutchan 2-Mar-17 5:56am

Do not post extra information as Solutions, edit your question. It just means people think you have been answered and there is no need to look at your question.

Also, I am still not sure exactly what problem you are trying to solve.

soulbog 2-Mar-17 6:19am

The problem was figuring out how to get the value of a b from inside factory from the hash map . Because when I add 2 entityId and base.put(entityId, new factory(entityId,arg1)); it creates 2 factory
and the solutions I posted gives me the values that i need, but just prints them but I can easily compare them if i have them