How to Initialize a Java HashMap Directly?

How to initialize a HashMap directly (in a literal way)?

Question:
Is it possible to initialize a Java HashMap in a concise way like this?

Map<String,String> test = 
    new HashMap<String, String>{"test":"test","test":"test"};

If so, what is the correct syntax?

Answer for Java Version 9 or higher:

Yes, this is now possible using factory methods added in Java 9:

// For up to 10 elements
Map<String, String> test1 = Map.of("a", "b", "c", "d");

// For any number of elements
import static java.util.Map.entry;
Map<String, String> test2 = Map.ofEntries(entry("a", "b"), entry("c", "d"));

Answer for up to Java Version 8:

Unfortunately, direct initialization in the provided syntax is not possible. However, you can use an anonymous subclass to shorten the code:

Map<String, String> myMap = new HashMap<String, String>() {{
    put("a", "b");
    put("c", "d");
}};

Alternatively, you can create a function for initialization:

Map<String, String> myMap = createMap();

private static Map<String, String> createMap() {
    Map<String,String> myMap = new HashMap<String,String>();
    myMap.put("a", "b");
    myMap.put("c", "d");
    return myMap;
}

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