CODEWITHSUNDEEP
javaandroid
user3718237
user3718237

Reputation:

Iterating through object in Hashmap

I need help trying to iterate through a Hashmap with objects. i got really stuck on how to do this. I tried checking on links like this How to iterate through objects in Hashmap but couldn't still implement it exactly as i want.

        List<Object> firstObject = new ArrayList<Object>();
        HashMap<Integer, Object> mapEx = new HashMap<> ();

        /* Put the data to Map*/

        mapEx.put(1, "First");       // String
        mapEx.put(2, 12.01);         // float
        mapEx.put(3, 12345);         // int
        mapEx.put(4, 600851475143L); // Long

        /* add map to firstObject */
        firstObject.add(mapEx);

        HashMap<String, Object> secondMap = new HashMap<> ();
        secondMap.put("mapEx", firstObject);

        Log.d("mapEx: ",secondMap.get("mapEx").toString()); 
        //When i print the line, this is the result below

        D/mapEx:﹕ [{4=600851475143, 1=First, 3=12345, 2=12.01}]

But How can i actually iterate through them? to come out this way.

4=600851475143
1=First
3=12345
2=12.01

and also maybe call each one by its key.

Thanks in advance.

Upvotes: 1

Views: 4723

Answers (2)

Manos Nikolaidis
Manos Nikolaidis

Reputation: 22254

The example you linked does answer the question. This how it would look like for your case :

for (Map.Entry<Integer, Object> entry : mapEx.entrySet()) {
    System.out.println(entry.getKey() + "=" + entry.getValue());
}

Also java 8 solution with streams

mapEx.entrySet().stream().forEach(e ->
    System.out.println(e.getKey() + "=" + e.getValue())
);

Tutorials about HashMaps here and here

And for streams here

Upvotes: 2

schrieveslaach
schrieveslaach

Reputation: 1819

Like this: 

for (HashMap<Object, Object> map : firstObject) {
    for (Object key : map.keySet()) {
        Object value = map.get(key);

        System.out.println("key = " + key + " value = " +  value);
    }
}

Upvotes: 0

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