In this post, we feature a comprehensive article about Java Unit Testing with Mockito Example.<\/p>\n
Java unit testing is a software testing which focuses on testing methods in a class. When a class depends on other classes and\/or interfaces, we can test it by using Mockito<\/a> to create and configure mock objects.<\/p>\n In this example, first, I will create a class which depends on an interface and other class. Second, I will test it using Mockito with Junit framework. I will demonstrate the following actions:<\/p>\n The example code in this article was built and run using:<\/p>\n In this step, I will demonstrate how to use Mockito in both JUnit 4 and JUnit 5 in a three-module Maven project:<\/p>\n Parent pom.xml<\/strong> includes three modules.<\/p>\n pom.xml<\/em><\/span> <\/p>\n In this step, I will create a common module which contains four classes:<\/p>\n The pom.xml<\/em><\/span> <\/p>\n In this step, I will create SomeInterface.java<\/em><\/span> <\/p>\n In this step, I will create OtherService.java<\/em><\/span> <\/p>\n In this step, I will create a SomeException.java<\/em><\/span> <\/p>\n In this step, I will create a SomeClass.java<\/em><\/span> <\/p>\n In this step, I will create a JUnit 4 test class to test The pom.xml<\/em><\/span> <\/p>\n In this step, I will create a SomeClassTest.java<\/em><\/span> <\/p>\n Output<\/em><\/span>\n[ulp id=’GhnY46zldrhgoeym’]<\/p>\n In this step, I will create a JUnit 5 test class to test The pom.xml<\/em><\/span> <\/p>\n In this step, I will create a SomeClassTest.java<\/em><\/span> <\/p>\n Output<\/em><\/span>\n<\/p>\n In this example, I demonstrated how to use Mockito to <\/p>\n\n
@Mock<\/code>.<\/li>\n@InjectMocks<\/code>.<\/li>\n2. Technologies Used<\/h2>\n
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3. Maven Project<\/h2>\n
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common<\/code> \u2013 includes four classes \u2013 SomeClass<\/code>, OtherService<\/code>, SomeInterface<\/code>, and SomeException<\/code>. SomeClass<\/code> depends on OtherService<\/code> and SomeInterface<\/code>.<\/li>\nJUnit4-demo<\/code>\u2013 tests SomeClass<\/code> with Mockito in JUnit 4.<\/li>\nJUnit5-demo<\/code> \u2013 tests SomeClass<\/code> with Mockito in JUnit 5.<\/li>\n<\/ul>\n3.1 Dependencies<\/h3>\n
<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<project xmlns=\"http:\/\/maven.apache.org\/POM\/4.0.0\"\n\txmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"\n\txsi:schemaLocation=\"http:\/\/maven.apache.org\/POM\/4.0.0 http:\/\/maven.apache.org\/xsd\/maven-4.0.0.xsd\">\n\t<modelVersion>4.0.0<\/modelVersion>\n\n\t<groupId>jcg.zheng.demo<\/groupId>\n\t<artifactId>junit-demo<\/artifactId>\n\t<version>0.0.1-SNAPSHOT<\/version>\n\t<packaging>pom<\/packaging>\n\n\t<name>junit-demo<\/name>\n\t<url>http:\/\/maven.apache.org<\/url>\n\n\t<properties>\n\t\t<project.build.sourceEncoding>UTF-8<\/project.build.sourceEncoding>\n\t<\/properties>\n\n\n\t<description>parent project for junit demo<\/description>\n\t<modules>\n\t\t<module>common<\/module>\n\t\t<module>junit4-demo<\/module>\n\t\t<module>junit5-demo<\/module>\n\t<\/modules>\n\n\t<build>\n\t\t<plugins>\n\t\t\t<plugin>\n\t\t\t\t<artifactId>maven-compiler-plugin<\/artifactId>\n\t\t\t\t<version>3.8.0<\/version>\n\t\t\t\t<configuration>\n\t\t\t\t\t<release>11<\/release>\n\t\t\t\t<\/configuration>\n\t\t\t<\/plugin>\n\t\t\t<plugin>\n\t\t\t\t<groupId>org.apache.maven.plugins<\/groupId>\n\t\t\t\t<artifactId>maven-surefire-plugin<\/artifactId>\n\t\t\t\t<version>3.0.0-M4<\/version>\n\t\t\t<\/plugin>\n\t\t\t <plugin>\n <groupId>org.apache.maven.plugins<\/groupId>\n <artifactId>maven-site-plugin<\/artifactId>\n <version>3.8.2<\/version>\n <\/plugin>\n\t\t<\/plugins>\n\t<\/build>\n\n\t<reporting>\n\t\t<plugins>\n\t\t\t<plugin>\n\t\t\t\t<groupId>org.apache.maven.plugins<\/groupId>\n\t\t\t\t<artifactId>maven-surefire-report-plugin<\/artifactId>\n\t\t\t\t<version>3.0.0-M4<\/version>\n\t\t\t<\/plugin>\n\t\t<\/plugins>\n\t<\/reporting>\n<\/project><\/pre>\n
4. Common Module<\/h2>\n
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OtherService<\/code> – a class which has three public methods.<\/li>\nSomeInterface<\/code> – an interface which defines two public methods.<\/li>\nSomeException<\/code> – a run time exception<\/li>\nSomeClass<\/code> – has four methods and depends on both OtherService<\/code> and SomeInterface<\/code>.<\/li>\n<\/ul>\n4.1 POM<\/h3>\n
common<\/code> module\u2019s pom.xml<\/strong> is defined as the following:<\/p>\n<?xml version=\"1.0\"?>\n<project\n\txsi:schemaLocation=\"http:\/\/maven.apache.org\/POM\/4.0.0 http:\/\/maven.apache.org\/xsd\/maven-4.0.0.xsd\"\n\txmlns=\"http:\/\/maven.apache.org\/POM\/4.0.0\"\n\txmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\">\n\t<modelVersion>4.0.0<\/modelVersion>\n\t<parent>\n\t\t<groupId>jcg.zheng.demo<\/groupId>\n\t\t<artifactId>junit-demo<\/artifactId>\n\t\t<version>0.0.1-SNAPSHOT<\/version>\n\t<\/parent>\n\n\t<artifactId>common<\/artifactId>\n\n\t<name>comon<\/name>\n\t<url>http:\/\/maven.apache.org<\/url>\n\n<\/project>\n<\/pre>\n
4.2 SomeInterface<\/h3>\n
SomeInterface<\/code> which has the following methods:<\/p>\n\n
doSomething<\/code> – it does not return anything.<\/li>\ngetSomeList<\/code> – it returns a list of string values.<\/li>\n<\/ul>\npackage jcg.zheng.demo;\n\nimport java.util.List;\n\npublic interface SomeInterface {\n\t\n\tvoid doSomething(String input);\n\t\n\tList<String> getSomeList(String input);\n\n}\n<\/pre>\n4.3 OtherService<\/h3>\n
OtherService<\/code>.<\/p>\npackage jcg.zheng.demo;\n\npublic class OtherService {\n\n\tpublic int calculateByDoubleIt(int num) {\n\t\treturn num * 2;\n\t}\n\t\n\tpublic void doSomething(String input) {\n\t\tif (\"Ok\".equalsIgnoreCase(input)) {\n\t\t\tSystem.out.println(\"do something.\");\n\t\t} else {\n\t\t\tthrow new RuntimeException(\"Remote service failed\");\n\t\t}\n\n\t}\n\t\n\tpublic boolean returnABoolean(String inputData) {\n\t\tif (\"Save\".equalsIgnoreCase(inputData)) {\n\t\t\treturn true;\n\t\t} else {\n\t\t\treturn false;\n\t\t}\n\t}\n}\n<\/pre>\n4.4 SomeException<\/h3>\n
SomeException<\/code> class which extends from RuntimeExcpetion<\/code>.<\/p>\npackage jcg.zheng.demo;\n\npublic class SomeException extends RuntimeException {\n\n\tprivate static final long serialVersionUID = 347808963459470775L;\n\t\n\tpublic SomeException(String msg) {\n\t\tsuper(msg);\n\t}\n\n}\n<\/pre>\n4.5 SomeClass<\/h3>\n
SomeClass<\/code> which depends on both SomeInterface<\/code> and OtherService<\/code>. It has the following methods:\n
doubleANumber<\/code> – returns an integer after invoking someService.calculateByDoubleIt<\/code>.<\/li>\nprocessData<\/code> – returns void<\/code>. It depends on someInterface.getSomeList<\/code> and someService.doSomething<\/code><\/li>\nreturnABoolean<\/code> – returns a Boolean<\/code> value after calling someService.returnABoolean<\/code><\/li>\nvoidFoo<\/code> – returns void<\/code>. It depends on someInterface.doSomething<\/code> and someService.doSomething<\/code>.<\/li>\n<\/ul>\npackage jcg.zheng.demo;\n\nimport java.util.List;\n\npublic class SomeClass {\n\n\tprivate SomeInterface someInterface;\n\n\tprivate OtherService someService;\n\n\tpublic int doubleANumber(int num) {\n\t\ttry {\n\t\t\treturn someService.calculateByDoubleIt(num);\n\t\t} catch (Exception e) {\n\t\t\tthrow new SomeException(\"External Service-calculateByDoubleIt failed \" + e.getMessage());\n\t\t}\n\t}\n\n\tpublic void processData(String input) {\n\t\tList<String> rawList = someInterface.getSomeList(input);\n\t\tif (rawList != null) {\n\t\t\tfor (String item : rawList) {\n\t\t\t\tsomeService.doSomething(item);\n\t\t\t}\n\t\t}\n\n\t}\n\n\tpublic boolean returnABoolean(String inputData) {\n\t\ttry {\n\t\t\treturn someService.returnABoolean(inputData);\n\t\t} catch (Exception e) {\n\t\t\tthrow new SomeException(\"External Service-returnABoolean failed \" + e.getMessage());\n\t\t}\n\t}\n\n\tpublic void voidFoo(String inputData) {\n\t\ttry {\n\t\t\tif (\"Interface\".equalsIgnoreCase(inputData)) {\n\t\t\t\tsomeInterface.doSomething(inputData);\n\t\t\t}\n\t\t\tsomeService.doSomething(inputData);\n\t\t} catch (Exception e) {\n\t\t\tthrow new SomeException(\"External Service-doSomething failed \" + e.getMessage());\n\t\t}\n\t}\n}\n<\/pre>\n5. JUnit 4 Test<\/h2>\n
SomeClass<\/code> with mocked SomeInterface<\/code> and OtherService<\/code>.<\/p>\n5.1 POM<\/h3>\n
JUnit4-demo<\/code> module\u2019s pom.xml<\/code> and depends on mockito-core<\/code> and the common<\/code> module.<\/p>\n<?xml version=\"1.0\"?>\n<project\n\txsi:schemaLocation=\"http:\/\/maven.apache.org\/POM\/4.0.0 http:\/\/maven.apache.org\/xsd\/maven-4.0.0.xsd\"\n\txmlns=\"http:\/\/maven.apache.org\/POM\/4.0.0\"\n\txmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\">\n\t<modelVersion>4.0.0<\/modelVersion>\n\t<parent>\n\t\t<groupId>jcg.zheng.demo<\/groupId>\n\t\t<artifactId>junit-demo<\/artifactId>\n\t\t<version>0.0.1-SNAPSHOT<\/version>\n\t<\/parent>\n\n\t<artifactId>junit4-demo<\/artifactId>\n\n\t<name>junit4-demo<\/name>\n\t<url>http:\/\/maven.apache.org<\/url>\n\t<properties>\n\t\t<junit.version>4.12<\/junit.version>\n\t<\/properties>\n\n\t<dependencies>\n\t\t<dependency>\n\t\t\t<groupId>jcg.zheng.demo<\/groupId>\n\t\t\t<artifactId>common<\/artifactId>\n\t\t\t<version>0.0.1-SNAPSHOT<\/version>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>junit<\/groupId>\n\t\t\t<artifactId>junit<\/artifactId>\n\t\t\t<version>${junit.version}<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\t\t<dependency>\n\t\t\t<groupId>org.mockito<\/groupId>\n\t\t\t<artifactId>mockito-core<\/artifactId>\n\t\t\t<version>3.2.4<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\t<\/dependencies>\n\n<\/project>\n<\/pre>\n5.2 SomeClassTest<\/h3>\n
SomeClassTest<\/code> class in JUnit 4. It will use the following Mockito annotation and libraries:<\/p>\n\n
when<\/code>, doThrow<\/code>, times<\/code>, and verify<\/code>.<\/li>\n<\/ul>\npackage jcg.zheng.demo.junit4;\n\nimport static org.junit.Assert.assertEquals;\nimport static org.junit.Assert.assertFalse;\nimport static org.junit.Assert.assertTrue;\nimport static org.junit.Assert.fail;\nimport static org.mockito.ArgumentMatchers.anyString;\nimport static org.mockito.Mockito.doThrow;\nimport static org.mockito.Mockito.times;\nimport static org.mockito.Mockito.verify;\nimport static org.mockito.Mockito.when;\n\nimport java.util.Arrays;\nimport java.util.List;\n\nimport org.junit.Test;\nimport org.junit.runner.RunWith;\nimport org.mockito.InjectMocks;\nimport org.mockito.Mock;\nimport org.mockito.junit.MockitoJUnitRunner;\n\nimport jcg.zheng.demo.SomeException;\nimport jcg.zheng.demo.SomeClass;\nimport jcg.zheng.demo.OtherService;\nimport jcg.zheng.demo.SomeInterface;\n\n@RunWith(MockitoJUnitRunner.class)\npublic class SomeClassTest {\n\n\t@InjectMocks\n\tprivate SomeClass classUnderTest;\n\t\n\t@Mock\n\tprivate SomeInterface mockedInterface;\n\n\t@Mock\n\tprivate OtherService mockedService;\n\n\t@Test\n\tpublic void test_doubleANumber() {\n\t\twhen(mockedService.calculateByDoubleIt(3)).thenReturn(6);\n\n\t\tassertEquals(6, classUnderTest.doubleANumber(3));\n\t\tverify(mockedService, times(1)).calculateByDoubleIt(3);\n\t}\n\n\t@Test(expected = SomeException.class)\n\tpublic void test_doubleANumber_exception() {\n\t\twhen(mockedService.calculateByDoubleIt(3)).thenThrow(NullPointerException.class);\n\t\tclassUnderTest.doubleANumber(3);\n\n\t\tverify(mockedService, times(1)).calculateByDoubleIt(3);\n\t}\n\n\t@Test\n\tpublic void test_processData() {\n\t\twhen(mockedInterface.getSomeList(anyString())).thenReturn(null);\n\t\tclassUnderTest.processData(\"NA\");\n\t\t\n\t\tverify(mockedInterface, times(1)).getSomeList(anyString());\n\t\tverify(mockedService, times(0)).doSomething(anyString());\n\t}\n\n\t@Test\n\tpublic void test_processData_2() {\n\t\tList<String> twoItemsList = Arrays.asList(\"Mary\", \"Zheng\");\n\t\twhen(mockedInterface.getSomeList(anyString())).thenReturn(twoItemsList);\n\t\tclassUnderTest.processData(\"NA\");\n\t\t\n\t\tverify(mockedInterface, times(1)).getSomeList(anyString());\n\t\tverify(mockedService, times(2)).doSomething(anyString());\n\t}\n\n\t@Test(expected = SomeException.class)\n\tpublic void test_returnBooleanFoo_exception() {\n\t\twhen(mockedService.returnABoolean(\"NA\")).thenThrow(NullPointerException.class);\n\t\tclassUnderTest.returnABoolean(\"NA\");\n\n\t\tverify(mockedService, times(1)).returnABoolean(\"NA\");\n\t}\n\n\t@Test\n\tpublic void test_returnBooleanFoo_false() {\n\t\twhen(mockedService.returnABoolean(\"NA\")).thenReturn(false);\n\n\t\tboolean shouldReturnFalse = classUnderTest.returnABoolean(\"NA\");\n\t\tassertFalse(shouldReturnFalse);\n\t}\n\n\t@Test\n\tpublic void test_returnBooleanFoo_true() {\n\t\twhen(mockedService.returnABoolean(\"Save\")).thenReturn(true);\n\n\t\tboolean shouldReturnTrue = classUnderTest.returnABoolean(\"Save\");\n\t\tassertTrue(shouldReturnTrue);\n\t\tverify(mockedService, times(1)).returnABoolean(\"Save\");\n\t}\n\n\t@Test\n\tpublic void test_voidFoo() throws IllegalAccessException {\n\t\ttry {\n\t\t\tclassUnderTest.voidFoo(\"Ok\");\n\t\t\tverify(mockedService, times(1)).doSomething(\"Ok\");\n\t\t\tverify(mockedInterface, times(0)).doSomething(anyString());\n\t\t} catch (Exception e) {\n\t\t\tfail(\"Should not throw exception\");\n\t\t}\n\t}\n\n\t\n\t@Test(expected = SomeException.class)\n\tpublic void test_voidFoo_exception() {\n\t\tdoThrow(IllegalStateException.class).when(mockedService).doSomething(\"NA\");\n\t\tclassUnderTest.voidFoo(\"NA\");\n\t}\n\t\n\t@Test\n\tpublic void test_voidFoo_interface() throws IllegalAccessException {\n\t\ttry {\n\t\t\tclassUnderTest.voidFoo(\"Interface\");\n\t\t\tverify(mockedService, times(1)).doSomething(\"Interface\");\n\t\t\tverify(mockedInterface, times(1)).doSomething(\"Interface\");\n\t\t} catch (Exception e) {\n\t\t\tfail(\"Should not throw exception\");\n\t\t}\n\t}\n}\n<\/pre>\n[INFO] Running jcg.zheng.demo.junit4.SomeClassTest\n[INFO] Tests run: 7, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.43 s - in jcg.zheng.demo.junit4.SomeClassTest\n[INFO]\n[INFO] Results:\n[INFO]\n[INFO] Tests run: 7, Failures: 0, Errors: 0, Skipped: 0<\/pre>\n
6. JUnit 5 Module<\/h2>\n
SomeClass<\/code> with mocked objects. <\/p>\n6.1 POM<\/h3>\n
JUnit5-demo<\/code> module\u2019s pom.xml<\/code> depends on JUnit 5 and common modules. Please note that it includes: junit-jupiter-engine <\/code>,junit-jupiter-api<\/code>, mockito-core<\/code>, and mockito-junit-jupiter<\/code>.<\/p>\n<?xml version=\"1.0\"?>\n<project\n\txsi:schemaLocation=\"http:\/\/maven.apache.org\/POM\/4.0.0 http:\/\/maven.apache.org\/xsd\/maven-4.0.0.xsd\"\n\txmlns=\"http:\/\/maven.apache.org\/POM\/4.0.0\"\n\txmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\">\n\t<modelVersion>4.0.0<\/modelVersion>\n\t<parent>\n\t\t<groupId>jcg.zheng.demo<\/groupId>\n\t\t<artifactId>junit-demo<\/artifactId>\n\t\t<version>0.0.1-SNAPSHOT<\/version>\n\t<\/parent>\n\n\t<artifactId>junit5-demo<\/artifactId>\n\n\t<name>junit5-demo<\/name>\n\t<url>http:\/\/maven.apache.org<\/url>\n\t<properties>\n\t\t<junit-jupiter.version>5.5.2<\/junit-jupiter.version>\n\t<\/properties>\n\n\t<dependencies>\n\t\t<dependency>\n\t\t\t<groupId>jcg.zheng.demo<\/groupId>\n\t\t\t<artifactId>common<\/artifactId>\n\t\t\t<version>0.0.1-SNAPSHOT<\/version>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>org.junit.jupiter<\/groupId>\n\t\t\t<artifactId>junit-jupiter-engine<\/artifactId>\n\t\t\t<version>${junit-jupiter.version}<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>org.junit.jupiter<\/groupId>\n\t\t\t<artifactId>junit-jupiter-api<\/artifactId>\n\t\t\t<version>${junit-jupiter.version}<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>org.junit.platform<\/groupId>\n\t\t\t<artifactId>junit-platform-runner<\/artifactId>\n\t\t\t<version>1.5.2<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\t\t<dependency>\n\t\t\t<groupId>org.mockito<\/groupId>\n\t\t\t<artifactId>mockito-core<\/artifactId>\n\t\t\t<version>3.2.4<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>org.mockito<\/groupId>\n\t\t\t<artifactId>mockito-junit-jupiter<\/artifactId>\n\t\t\t<version>2.23.0<\/version>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\n\t<\/dependencies>\n\n\n<\/project>\n<\/pre>\n6.2 SomeClassTest<\/h3>\n
SomeClassTest<\/code> class in JUnit 5. It has the same annotations as Junit 4, the only difference is Junit 5 uses @ExtendWith(MockitoExtension.class)<\/code>.<\/p>\npackage jcg.zheng.demo.junit5;\n\nimport static org.junit.jupiter.api.Assertions.assertEquals;\nimport static org.junit.jupiter.api.Assertions.assertFalse;\nimport static org.junit.jupiter.api.Assertions.assertThrows;\nimport static org.junit.jupiter.api.Assertions.assertTrue;\nimport static org.mockito.ArgumentMatchers.anyString;\nimport static org.mockito.Mockito.doThrow;\nimport static org.mockito.Mockito.times;\nimport static org.mockito.Mockito.verify;\nimport static org.mockito.Mockito.when;\n\nimport java.util.Arrays;\nimport java.util.List;\n\nimport org.junit.jupiter.api.DisplayName;\nimport org.junit.jupiter.api.Test;\nimport org.junit.jupiter.api.extension.ExtendWith;\nimport org.mockito.InjectMocks;\nimport org.mockito.Mock;\nimport org.mockito.junit.jupiter.MockitoExtension;\n\nimport jcg.zheng.demo.SomeException;\nimport jcg.zheng.demo.SomeClass;\nimport jcg.zheng.demo.OtherService;\nimport jcg.zheng.demo.SomeInterface;\n\n@ExtendWith(MockitoExtension.class)\npublic class SomeClassTest {\n\n\t@InjectMocks\n\tprivate SomeClass classUnderTest;\n\n\t@Mock\n\tprivate SomeInterface mockedInterface;\n\n\t@Mock\n\tprivate OtherService mockedService;\n\n\t@Test\n\t@DisplayName(\"It should double a number\")\n\tpublic void test_doubleANumber() {\n\t\twhen(mockedService.calculateByDoubleIt(3)).thenReturn(6);\n\n\t\tassertEquals(6, classUnderTest.doubleANumber(3));\n\t\tverify(mockedService, times(1)).calculateByDoubleIt(3);\n\t}\n\n\t@Test\n\tpublic void test_doubleANumber_exception() {\n\t\twhen(mockedService.calculateByDoubleIt(3)).thenThrow(NullPointerException.class);\n\n\t\tassertThrows(SomeException.class, () -> {\n\t\t\tclassUnderTest.doubleANumber(3);\n\t\t});\n\n\t\tverify(mockedService, times(1)).calculateByDoubleIt(3);\n\t}\n\n\t@Test\n\tpublic void test_processData() {\n\t\twhen(mockedInterface.getSomeList(anyString())).thenReturn(null);\n\t\tclassUnderTest.processData(\"NA\");\n\n\t\tverify(mockedInterface, times(1)).getSomeList(anyString());\n\t\tverify(mockedService, times(0)).doSomething(anyString());\n\t}\n\n\t@Test\n\tpublic void test_processData_2() {\n\t\tList<String> twoItemsList = Arrays.asList(\"Mary\", \"Zheng\");\n\t\twhen(mockedInterface.getSomeList(anyString())).thenReturn(twoItemsList);\n\t\tclassUnderTest.processData(\"NA\");\n\n\t\tverify(mockedInterface, times(1)).getSomeList(anyString());\n\t\tverify(mockedService, times(2)).doSomething(anyString());\n\t}\n\n\t@Test\n\tpublic void test_returnBooleanFoo_exception() {\n\t\twhen(mockedService.returnABoolean(\"NA\")).thenThrow(NullPointerException.class);\n\t\tassertThrows(SomeException.class, () -> {\n\t\t\tclassUnderTest.returnABoolean(\"NA\");\n\t\t});\n\n\t\tverify(mockedService, times(1)).returnABoolean(\"NA\");\n\t}\n\n\t@Test\n\tpublic void test_returnBooleanFoo_false() {\n\t\twhen(mockedService.returnABoolean(\"NA\")).thenReturn(false);\n\n\t\tboolean shouldReturnFalse = classUnderTest.returnABoolean(\"NA\");\n\t\tassertFalse(shouldReturnFalse);\n\t}\n\n\t@Test\n\tpublic void test_returnBooleanFoo_true() {\n\t\twhen(mockedService.returnABoolean(\"Save\")).thenReturn(true);\n\n\t\tboolean shouldReturnTrue = classUnderTest.returnABoolean(\"Save\");\n\t\tassertTrue(shouldReturnTrue);\n\t\tverify(mockedService, times(1)).returnABoolean(\"Save\");\n\t}\n\n\t@Test\n\tpublic void test_voidFoo() throws IllegalAccessException {\n\n\t\tclassUnderTest.voidFoo(\"OK\");\n\t\tverify(mockedService, times(1)).doSomething(\"OK\");\n\n\t}\n\n\t@Test\n\tpublic void test_voidFoo_exception() {\n\t\tdoThrow(IllegalStateException.class).when(mockedService).doSomething(\"NA\");\n\t\tassertThrows(SomeException.class, () -> {\n\t\t\tclassUnderTest.voidFoo(\"NA\");\n\t\t});\n\n\t}\n\n\t@Test\n\tpublic void test_voidFoo_interface() throws IllegalAccessException {\n\n\t\tclassUnderTest.voidFoo(\"Interface\");\n\t\tverify(mockedService, times(1)).doSomething(\"Interface\");\n\t\tverify(mockedInterface, times(1)).doSomething(\"Interface\");\n\n\t}\n\n}\n<\/pre>\n[INFO] Running jcg.zheng.demo.junit5.SomeClassTest\n[INFO] Tests run: 10, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 1.042 s - in jcg.zheng.demo.junit5.SomeClassTest\n[INFO]\n[INFO] Results:\n[INFO]\n[INFO] Tests run: 10, Failures: 0, Errors: 0, Skipped: 0<\/pre>\n
7. Summary<\/h2>\n
\n
@Mock<\/code>.<\/li>\n@InjectMocks<\/code>.<\/li>\nstatic<\/code> method to mock the object’s behavior.<\/li>\n8. Download the Source Code<\/h2>\n