get string value from HashMap depending on key name

user_155695 0
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I have a HashMap with various keys and values, how can I get one value out?

I have a key in the map called my_code, it should contain a string, how can I just get that without having to iterate through the map?

So far I've got..

   HashMap newMap = new HashMap(paramMap);
   String s = newMap.get("my_code").toString();

I'm expecting to see a String, such as "ABC" or "DEF" as that is what I put in there initially, but if I do a System.out.println() I get something like java.lang.string#F0454

Sorry, I'm not too familiar with maps as you can probably guess ;)

hashmap collections java
10 Answers

This is another example of how to use keySet(), get(), values() and entrySet() functions to obtain Keys and Values in a Map:

        Map<Integer, String> testKeyset = new HashMap<Integer, String>();

        testKeyset.put(1, "first");
        testKeyset.put(2, "second");
        testKeyset.put(3, "third");
        testKeyset.put(4, "fourth");

        // Print a single value relevant to a specified Key. (uses keySet())
        for(int mapKey: testKeyset.keySet())
            System.out.println(testKeyset.get(mapKey));

        // Print all values regardless of the key.
        for(String mapVal: testKeyset.values())
            System.out.println(mapVal.trim());

        // Displays the Map in Key-Value pairs (e.g: [1=first, 2=second, 3=third, 4=fourth])
        System.out.println(testKeyset.entrySet());
user_36819340 
 HashMap<Integer, String> hmap = new HashMap<Integer, String>();
 hmap.put(4, "DD");

The Value mapped to Key 4 is DD

user_103580460
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