mockTest.java

public class SecurityCentralTest {
    Window windowMock = mock(Window.class);
    Door doorMock = mock(Door.class);

    @Test
    public void enabling_security_locks_windows_and_doors() {
        SecurityCentral securityCentral = new SecurityCentral(windowMock, doorMock);
        securityCentral.securityOn();
        verify(doorMock).close();
        verify(windowMock).close();
    }
}