Replacing if else statement with pattern

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I have a if else statement which might grow in the near future.

    public void decide(String someCondition){


        }else if(someCondition.equals("conditionTwo")){





Since, this is already looking messy, I think it would be better if I can apply any design patterns here. I looked into Strategy pattern but I am not sure if that will reduce if else condition here. Any suggestions?


This is a classic Replace Condition dispatcher with Command in the Refactoring to Patterns book.

enter image description here

Basically you make a Command object for each of the blocks of code in your old if/else group and then make a Map of those commands where the keys are your condition Strings

interface Handler{
    void handle( myObject o);

 Map<String, Handler> commandMap = new HashMap<>();
 //feel free to factor these out to their own class or
 //if using Java 8 use the new Lambda syntax
 commandMap.put("conditionOne", new Handler(){
         void handle(MyObject o){
                //get desired parameters from MyObject and do stuff

Then instead of your if/else code it is instead:


Now if you need to later add new commands, you just add to the hash.

If you want to handle a default case, you can use the Null Object pattern to handle the case where a condition isn’t in the Map.

 Handler defaultHandler = ...


Source: stackoverflow