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 Mockito's spy mechanism:

A a = new A();
A aSpy = Mockito.spy(a);
Mockito.when(aSpy.method1()).thenReturn(5l);

The use of a spy calls the default behavior of the wrapped object for any method that is not stubbed.

Mockito.spy()/@Spy