Mocking static methods with Mockito

Question

I\'ve written a factory to produce java.sql.Connection objects:

public class MySQLDatabaseConnectionFactory implements DatabaseConnectionFactory         


        

Answer 1

Observation : When you call static method within a static entity, you need to change the class in @PrepareForTest.

For e.g. :

securityAlgo = MessageDigest.getInstance(SECURITY_ALGORITHM);

For the above code if you need to mock MessageDigest class, use

@PrepareForTest(MessageDigest.class)

While if you have something like below :

public class CustomObjectRule {

    object = DatatypeConverter.printHexBinary(MessageDigest.getInstance(SECURITY_ALGORITHM)
             .digest(message.getBytes(ENCODING)));

}

then, you'd need to prepare the class this code resides in.

@PrepareForTest(CustomObjectRule.class)

And then mock the method :

PowerMockito.mockStatic(MessageDigest.class);
PowerMockito.when(MessageDigest.getInstance(Mockito.anyString()))
      .thenThrow(new RuntimeException());