How to mock a single method in java

Question

Is it possible to Mock a single method of a Java class?

For example:

class A {
    long method1();
    String method2();
    int method3();
}


// in         


        

Answer 1

Use the spy() method from Mockito, and mock your method like this:

import static org.mockito.Mockito.*;

...

A a = spy(new A());
when(a.method1()).thenReturn(10L);