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javatypeshashmapalias

How do I create some variable type alias in Java?


Let's say I have this code

Map<String, String> list = new HashMap<String, String>();
list.put("number1", "one");
list.put("number2", "two");

how can I make some "alias" the type

Map<String, String>

to something that easier to be rewritten like

// may be something like this
theNewType = HashMap<String, String>;

theNewType list = new theNewType();
list.put("number1", "one");
list.put("number2", "two");

Basically, my question is, how to create "alias" to some "type", so I can make it easier to write and easier when need to change the whole program code.

Thanks, and sorry if this is silly question. I'm kinda new in Java.


Solution

  • There are no aliases in Java. You can extend the HashMap class with your class like this:

    public class TheNewType extends HashMap<String, String> {
        // default constructor
        public TheNewType() {
            super();
        }
        // you need to implement the other constructors if you need
    }
    

    But keep in mind that this will be a class it won't be the same as you type HashMap<String, String>