How to mock a class and its inner static class using Powermock

Question

I have a class as :

public class SomeClass {    
    private String someField;    
    public SomeClass(String field) {
        someField = field;
    }

    public String getUrl() {    
        return "http://" + someField;
    }

    public static class Builder {  
        private String uri;    
        public Builder(String url) {
            this.uri = url;
        }    
        public SomeClass build() {  
            return new SomeClass(uri);
        }
    }
}

The above class is being called from another class as:

class MainClass {    
    private SomeClass someClass;    
    public boolean isUrlAvailable() {
        someClass = new SomeClass.Builder("myURI").build();
        String url = someClass.getUrl();
        if (url != null && url.length() > 10) {
            return true;
        }
        return false;
    }
}

My requirement is to test the MainClass, for which I need to mock SomeClass and SomeClass.Builder class. I tried to mock the two classes but could not successfully achieve the requirement.

Answer 1

The code you are showing should not require you to mock anything. It only uses that builder to build something. Assuming that you have tested SomeClass/Builder on its own - you just verify that method in Main gives the correct result.

Anyway: mocking a static class is possible - see here. The only thing to pay attention of: to get all the pre-conditions right, for example to have the required annotations:

RunWith(PowerMockRunner.class)
@PrepareForTest(SomeClassBuilderClass.class)

Beyond that: you don't to mock anything static in the first place. Your only problem is the call to new!

And - the real answer here: simply pass in that instance of SomeClass to work in (instead of calling new Builder inside of the method under test)!