java - Use Mockito to mock some methods but not others -

is there way, using mockito, mock methods in class, not others?

for example, in (admittedly contrived) stock class want mock getprice() , getquantity() return values (as shown in test snippet below) want getvalue() perform multiplication coded in stock class

public class stock {   private final double price;   private final int quantity;    stock(double price, int quantity) {     this.price = price;     this.quantity = quantity;   }    public double getprice() {     return price;   }    public int getquantity() {     return quantity;   }   public double getvalue() {     return getprice() * getquantity();   }    @test   public void getvaluetest() {     stock stock = mock(stock.class);     when(stock.getprice()).thenreturn(100.00);     when(stock.getquantity()).thenreturn(200);     double value = stock.getvalue();     // unfortunately following assert fails, because mock stock getvalue() method not perform stock.getvalue() calculation code.     assertequals("stock value not correct", 100.00*200, value, .00001); } 

to directly answer question, yes, can mock methods without mocking others. called partial mock. see the mockito documentation on partial mocks more information.

for example, can following, in test:

stock stock = mock(stock.class); when(stock.getprice()).thenreturn(100.00);    // mock implementation when(stock.getquantity()).thenreturn(200);    // mock implementation when(stock.getvalue()).thencallrealmethod();  // real implementation 

in case, each method implementation mocked, unless specify thencallrealmethod() in when(..) clause.

there possibility other way arround spy instead of mock:

stock stock = spy(stock.class); when(stock.getprice()).thenreturn(100.00);    // mock implementation when(stock.getquantity()).thenreturn(200);    // mock implementation // other method call use real implementations 

in case, method implementation real one, except if have defined mocked behaviour when(..).

there 1 important pitfall when use when(object) spy in previous example. real method called (because stock.getprice() evaluated before when(..) @ runtime). can problem if method contains logic should not called. can write previous example this:

stock stock = spy(stock.class); doreturn(100.00).when(stock).getprice();    // mock implementation doreturn(200).when(stock).getquantity();    // mock implementation // other method call use real implementations 

---

however, example, believe still fail, since implementation of getvalue() relies on quantity , price, rather getquantity() , getprice(), you've mocked.

what seems want just:

@test public void getvaluetest() {     stock stock = new stock(100.00, 200);     double value = stock.getvalue();     assertequals("stock value not correct", 100.00*200, value, .00001); }