I have a class where inside a void method it does a new instance creation

public class BaseDao {
        protected void setDataSource(DataSource dataSource) {
            this.defaultTemplate = new JdbcTemplate(dataSource);
        }
}

Now in my Test Class for BaseDao i would like to return a mock when a new instance of JdbcTemplate is created with dataSource arguments instead of a new instance.

@ExtendWith(MockitoExtension.class)
public class BaseDaoTest {
    
    @Mock
    private JdbcTemplate defaultTemplate;

    @Test
    public void testSetDataSource() throws SQLException {
        when(<what to do here?>).thenReturn(mockedDefaultTemplate) //here when new instance of JdbcTemplate is created i would like to return this mockedDefaultTemplate
    }
}

This is possible in PowerMock using whenNew however i don’t want to use PowerMock because it does not have junit 5 support and in general i dont like powerMock.

Please advise how can i do this.