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Mockito mock objects library core API and implementation

There is a newer version: 5.12.0

/*
 * Copyright (c) 2007 Mockito contributors
 * This program is made available under the terms of the MIT License.
 */

package org.mockito;

import org.mockito.exceptions.base.MockitoException;
import org.mockito.internal.configuration.GlobalConfiguration;
import org.mockito.junit.MockitoJUnitRunner;
import org.mockito.plugins.AnnotationEngine;

/**
 * MockitoAnnotations.initMocks(this); initializes fields annotated with Mockito annotations.
 *   
 * 

 * Allows shorthand creation of objects required for testing. 
 * Minimizes repetitive mock creation code. 
 * Makes the test class more readable.
 * Makes the verification error easier to read because field name is used to identify the mock.
 * 
 * 
 * 
 *   public class ArticleManagerTest extends SampleBaseTestCase { 
 *     
 *       @Mock private ArticleCalculator calculator;
 *       @Mock private ArticleDatabase database;
 *       @Mock private UserProvider userProvider;
 *     
 *       private ArticleManager manager;
 *     
 *       @Before public void setup() {
 *           manager = new ArticleManager(userProvider, database, calculator);
 *       }
 *   }
 *   
 *   public class SampleBaseTestCase {
 *   
 *       @Before public void initMocks() {
 *           MockitoAnnotations.initMocks(this);
 *       }
 *   }
 * 
 * 
 * Read also about other annotations @{@link Spy}, @{@link Captor}, @{@link InjectMocks}
 * 

 * MockitoAnnotations.initMocks(this) method has to called to initialize annotated fields.
 * 

 * In above example, initMocks() is called in @Before (JUnit4) method of test's base class. 
 * For JUnit3 initMocks() can go to setup() method of a base class.
 * You can also put initMocks() in your JUnit runner (@RunWith) or use built-in runner: {@link MockitoJUnitRunner}
 */
public class MockitoAnnotations {

    /**
     * Initializes objects annotated with Mockito annotations for given testClass:
     *  @{@link org.mockito.Mock}, @{@link Spy}, @{@link Captor}, @{@link InjectMocks} 
     * 
     * See examples in javadoc for {@link MockitoAnnotations} class.
     */
    public static void initMocks(Object testClass) {
        if (testClass == null) {
            throw new MockitoException("testClass cannot be null. For info how to use @Mock annotations see examples in javadoc for MockitoAnnotations class");
        }

        AnnotationEngine annotationEngine = new GlobalConfiguration().tryGetPluginAnnotationEngine();
        annotationEngine.process(testClass.getClass(), testClass);
    }
}