BAEL-2399: Guice vs Spring - Dependency Injection

2018-12-23 16:41:11 -05:00
parent 3df9e64050
commit 8880d96d3a
19 changed files with 531 additions and 0 deletions
@@ -0,0 +1,72 @@
+package com.baeldung.examples;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import org.junit.Test;
+
+import com.baeldung.examples.common.BookService;
+import com.baeldung.examples.guice.Employee;
+import com.baeldung.examples.guice.FooGenerator;
+import com.baeldung.examples.guice.GuiceUser;
+import com.baeldung.examples.guice.GuiceUserService;
+import com.baeldung.examples.guice.Person;
+import com.baeldung.examples.guice.modules.GuiceModule;
+import com.google.inject.Guice;
+import com.google.inject.Injector;
+
+public class GuiceTests {
+
+    @Test
+    public void givenAccountFieldInjectedInGuiceUser_WhenGetAccountInvoked_ThenReturnValueIsNotNull() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        GuiceUser guiceUser = injector.getInstance(GuiceUser.class);
+        assertNotNull(guiceUser.getAccount());
+    }
+
+    @Test
+    public void givenAccountServiceInjectedInGuiceUserService_WhenGetAccountServiceInvoked_ThenReturnValueIsNotNull() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        GuiceUserService guiceUserService = injector.getInstance(GuiceUserService.class);
+        assertNotNull(guiceUserService.getAccountService());
+    }
+
+    @Test
+    public void givenBookServiceIsRegisteredInModule_WhenBookServiceIsInjected_ThenReturnValueIsNotNull() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        BookService bookService = injector.getInstance(BookService.class);
+        assertNotNull(bookService);
+    }
+
+    @Test
+    public void givenFooGeneratorConstructorParameterIsNotNullable_WhenFooGeneratorIsInjected_ThenTestFailsByProvisionException() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        FooGenerator fooGenerator = injector.getInstance(FooGenerator.class);
+        assertNotNull(fooGenerator);
+    }
+
+    @Test
+    public void givenMultipleBindingsForPerson_WhenPersonIsInjected_ThenTestFailsByProvisionException() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        Person person = injector.getInstance(Person.class);
+        assertNotNull(person);
+    }
+
+    @Test
+    public void givenEmployeeConstructorAnnotatedByInject_WhenEmployeeIsInjected_ThenInstanceWillBeCreatedFromTheConstructor() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        Employee employee = injector.getInstance(Employee.class);
+        assertNotNull(employee);
+        assertEquals("Default", employee.getLastName());
+    }
+
+    @Test
+    public void givenAddressAutowiredToGuiceUserBySetterInjection_WhenGuiceUserIsInjected_ThenAddressInitializedByTheSetter() {
+        Injector injector = Guice.createInjector(new GuiceModule());
+        GuiceUser guiceUser = injector.getInstance(GuiceUser.class);
+        assertNotNull(guiceUser);
+        assertNotNull(guiceUser.getAddress());
+        assertEquals("Default", guiceUser.getAddress().getCity());
+    }
+
+}
@@ -0,0 +1,58 @@
+package com.baeldung.examples;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringRunner;
+
+import com.baeldung.examples.common.BookService;
+import com.baeldung.examples.spring.AppConfig;
+import com.baeldung.examples.spring.SpringUser;
+import com.baeldung.examples.spring.Student;
+import com.baeldung.examples.spring.UserService;
+
+@RunWith(SpringRunner.class)
+@ContextConfiguration(classes = { AppConfig.class })
+public class SpringTests {
+    @Autowired
+    ApplicationContext context;
+
+    @Test
+    public void givenAccountFieldAutowiredToSpringUser_WhenGetAccountInvoked_ThenReturnValueIsNotNull() {
+        SpringUser springUser = context.getBean(SpringUser.class);
+        assertNotNull(springUser.getAccount());
+    }
+
+    @Test
+    public void givenAccountServiceFieldAutowiredToUserService_WhenGetAccountServiceInvoked_ThenReturnValueIsNotNull() {
+        UserService userService = context.getBean(UserService.class);
+        assertNotNull(userService.getAccountService());
+    }
+
+    @Test
+    public void givenBookServiceIsRegisteredAsBeanInContext_WhenBookServiceIsRetrievedFromContext_ThenReturnValueIsNotNull() {
+        BookService bookService = context.getBean(BookService.class);
+        assertNotNull(bookService);
+    }
+
+    @Test
+    public void givenStudentConstructorAnnotatedByAutowired_WhenStudentIsRetrievedFromContext_ThenInstanceWillBeCreatedFromTheConstructor() {
+        Student student = context.getBean(Student.class);
+        assertNotNull(student);
+        assertEquals("Default", student.getFirstName());
+        assertEquals("Default", student.getLastName());
+    }
+
+    @Test
+    public void givenAddressAutowiredToSpringUserBySetterInjection_WhenSpringUserRetrievedFromContext_ThenAddressInitializedByTheSetter() {
+        SpringUser springUser = context.getBean(SpringUser.class);
+        assertNotNull(springUser.getAddress());
+        assertEquals("Default", springUser.getAddress().getCity());
+    }
+
+}