junit - doNothing void method with params in other class -

i have 2 classes:

public class aclass{    public void meth1(){       bclass b = new bclass();       b.meth2();// dont want call method       //buss logic    } }  public class bclass{    public void meth2(){       // logic    }  } 

currently creating junit test case meth1 in aclass. however, don't want call meth2 in bclass, execute busslogic in aclass.

the classes aclass , bclass fixed - cannot(and won't) change code on aclass , bclass.

i tried many things @injectmock , donothing using mokito , power mock, meth2 gets called when calling meth1 in aclass.

what can fix this?

you can powermockito. link explains details. below how might example.

@runwith(powermockrunner.class) @preparefortest(aclass.class) public class aclasstesting {      @mock     bclass mockb;       @test     public void testmeth1(){          //prepare mocks         whennew(bclass.class).withnoarguments().thenreturn(mockb);         donothing().when(mockb).meth2();          //run         aclass instance = new aclass();         aclass.meth1();          //asserts , verify         verifynew(bclass.class).withnoarguments();         verify(mockb, times(1)).meth2();     }  } 

edit:

when mock out bclass instance using @mock replaces methods in instance mock methods. if want mock of methods in bclas, must spy bclass instance instead of mocking it. spy mocks methods want. replace @mock @spy in example meth2 blocked not other methods in bclass.