PackageBasedClassFinderTest.java

package com.epam.wilma.stubconfig.initializer.support.helper;

/*==========================================================================
Copyright 2013-2017 EPAM Systems

This file is part of Wilma.

Wilma is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Wilma is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with Wilma.  If not, see <http://www.gnu.org/licenses/>.
===========================================================================*/

import static org.mockito.BDDMockito.given;
import static org.mockito.Mockito.verify;
import static org.testng.AssertJUnit.assertNotNull;

import java.util.HashSet;
import java.util.Set;

import org.mockito.InjectMocks;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.mockito.internal.util.reflection.Whitebox;
import org.slf4j.Logger;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

/**
 * Unit test for {@link PackageBasedClassFinder}.
 * @author Adam_Csaba_Kiraly
 *
 */
public class PackageBasedClassFinderTest {

    private static final String PACKAGE_NAME = "a.b.c";
    private static final Class<Object> INTERFACE_OR_CLASS = Object.class;

    private static final String MULTIPLE_CLASSES_FOUND_TEMPLATE = "Warning! Multiple classes found '%s' in package '%s' as subtype of '%s'.";

    @Mock
    private PackageBasedClassFinderCore packageBasedClassFinderCore;

    @InjectMocks
    private PackageBasedClassFinder underTest;

    @Mock
    private Logger logger;

    @BeforeMethod
    public void setUp() throws Exception {
        MockitoAnnotations.initMocks(this);
        Whitebox.setInternalState(underTest, "logger", logger);
    }

    @Test
    public void testFindFirstOfShouldNotReturnNull() throws ClassNotFoundException {
        //GIVEN
        Set<Class<? extends Object>> value = new HashSet<>();
        value.add(Object.class);
        given(packageBasedClassFinderCore.find(PACKAGE_NAME, INTERFACE_OR_CLASS)).willReturn(value);
        //WHEN
        Class<? extends Object> result = underTest.findFirstOf(INTERFACE_OR_CLASS, PACKAGE_NAME);
        //THEN
        assertNotNull(result);
    }

    @Test(expectedExceptions = ClassNotFoundException.class)
    public void testFindFirstOfShouldThrowClassNotFoundExceptionWhenNoClassIsFound() throws ClassNotFoundException {
        //GIVEN
        Set<Class<? extends Object>> value = new HashSet<>();
        given(packageBasedClassFinderCore.find(PACKAGE_NAME, INTERFACE_OR_CLASS)).willReturn(value);
        //WHEN
        underTest.findFirstOf(INTERFACE_OR_CLASS, PACKAGE_NAME);
        //THEN exception is thrown
    }

    @Test
    public void testFindFirstOfShouldWarnIfMoreClassesAreFound() throws ClassNotFoundException {
        //GIVEN
        Set<Class<? extends Object>> value = new HashSet<>();
        value.add(Object.class);
        value.add(String.class);
        given(packageBasedClassFinderCore.find(PACKAGE_NAME, INTERFACE_OR_CLASS)).willReturn(value);
        //WHEN
        underTest.findFirstOf(INTERFACE_OR_CLASS, PACKAGE_NAME);
        //THEN
        String expected = String.format(MULTIPLE_CLASSES_FOUND_TEMPLATE, value, PACKAGE_NAME, INTERFACE_OR_CLASS);
        verify(logger).info(expected);
    }
}