BAEL-4094: Code example for Spring ApplicationContext article (#9656)

spring-core-4/pom.xml

@@ -24,6 +24,16 @@
             <artifactId>spring-core</artifactId>
             <version>${spring.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-web</artifactId>
+            <version>${spring.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-webmvc</artifactId>
+            <version>${spring.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-expression</artifactId>
@@ -69,6 +79,12 @@
             <version>${assertj-core.version}</version>
             <scope>test</scope>
         </dependency>
+        <dependency>
+            <groupId>javax.servlet</groupId>
+            <artifactId>javax.servlet-api</artifactId>
+            <version>4.0.0</version>
+        </dependency>
+
     </dependencies>
 
     <build>

spring-core-4/src/main/java/com/baeldung/applicationcontext/AccountConfig.java

@@ -0,0 +1,28 @@
+package com.baeldung.applicationcontext;
+
+import org.springframework.context.MessageSource;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.support.ResourceBundleMessageSource;
+
+@Configuration
+public class AccountConfig {
+
+    @Bean
+    public AccountService accountService() {
+        return new AccountService(accountRepository());
+    }
+
+    @Bean
+    public AccountRepository accountRepository() {
+        return new AccountRepository();
+    }
+
+    @Bean
+    public MessageSource messageSource() {
+        ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();
+        messageSource.setBasename("config/messages");
+        return messageSource;
+    }
+
+}

spring-core-4/src/main/java/com/baeldung/applicationcontext/AccountRepository.java

@@ -0,0 +1,5 @@
+package com.baeldung.applicationcontext;
+
+public class AccountRepository {
+
+}

spring-core-4/src/main/java/com/baeldung/applicationcontext/AccountService.java

@@ -0,0 +1,32 @@
+package com.baeldung.applicationcontext;
+
+import java.util.Locale;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.MessageSource;
+
+public class AccountService {
+
+    @Autowired
+    private AccountRepository accountRepository;
+
+    @Autowired
+    private MessageSource messageSource;
+
+    public void setAccountRepository(AccountRepository accountRepository) {
+        this.accountRepository = accountRepository;
+    }
+
+    public AccountRepository getAccountRepository() {
+        return accountRepository;
+    }
+
+    public AccountService(AccountRepository accountRepository) {
+        this.accountRepository = accountRepository;
+    }
+
+    public String getAccountName() {
+        return messageSource.getMessage("account.name", null, Locale.ENGLISH);
+    }
+
+}

spring-core-4/src/main/java/com/baeldung/applicationcontext/MyWebApplicationInitializer.java

@@ -0,0 +1,24 @@
+package com.baeldung.applicationcontext;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRegistration;
+
+import org.springframework.web.WebApplicationInitializer;
+import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
+import org.springframework.web.servlet.DispatcherServlet;
+
+public class MyWebApplicationInitializer implements WebApplicationInitializer {
+
+    public void onStartup(ServletContext container) throws ServletException {
+        AnnotationConfigWebApplicationContext context = new AnnotationConfigWebApplicationContext();
+        context.register(AccountConfig.class);
+        context.setServletContext(container);
+
+        ServletRegistration.Dynamic servlet = container.addServlet("dispatcher", new DispatcherServlet(context));
+        servlet.setLoadOnStartup(1);
+
+        servlet.addMapping("/");
+    }
+
+}

spring-core-4/src/main/java/com/baeldung/applicationcontext/MyXmlWebApplicationInitializer.java

@@ -0,0 +1,24 @@
+package com.baeldung.applicationcontext;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletException;
+import javax.servlet.ServletRegistration;
+
+import org.springframework.web.WebApplicationInitializer;
+import org.springframework.web.context.support.XmlWebApplicationContext;
+import org.springframework.web.servlet.DispatcherServlet;
+
+public class MyXmlWebApplicationInitializer implements WebApplicationInitializer {
+
+    public void onStartup(ServletContext container) throws ServletException {
+        XmlWebApplicationContext context = new XmlWebApplicationContext();
+        context.setConfigLocation("/WEB-INF/spring/applicationContext.xml");
+        context.setServletContext(container);
+
+        ServletRegistration.Dynamic servlet = container.addServlet("dispatcher", new DispatcherServlet(context));
+        servlet.setLoadOnStartup(1);
+
+        servlet.addMapping("/");
+    }
+
+}

spring-core-4/src/main/java/com/baeldung/applicationcontext/UserService.java

@@ -0,0 +1,10 @@
+package com.baeldung.applicationcontext;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class UserService {
+
+    // user service code
+
+}

spring-core-4/src/test/java/com/baeldung/applicationcontext/ApplicationContextUnitTest.java

@@ -0,0 +1,71 @@
+package com.baeldung.applicationcontext;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
+import org.junit.Ignore;
+import org.junit.Test;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.support.ClassPathXmlApplicationContext;
+import org.springframework.context.support.FileSystemXmlApplicationContext;
+
+public class ApplicationContextUnitTest {
+
+    @Test
+    public void givenAnnotationConfigAppContext_whenSpringConfig_thenMappingSuccess() {
+        ApplicationContext context = new AnnotationConfigApplicationContext(AccountConfig.class);
+        AccountService accountService = context.getBean(AccountService.class);
+
+        assertNotNull(accountService);
+        assertNotNull(accountService.getAccountRepository());
+
+        ((AnnotationConfigApplicationContext) context).close();
+    }
+
+    @Test
+    public void givenClasspathXmlAppContext_whenAnnotationConfig_thenMappingSuccess() {
+        ApplicationContext context = new ClassPathXmlApplicationContext("applicationcontext/user-bean-config.xml");
+        UserService userService = context.getBean(UserService.class);
+
+        assertNotNull(userService);
+
+        ((ClassPathXmlApplicationContext) context).close();
+    }
+
+    @Test
+    @Ignore
+    public void givenFileXmlAppContext_whenXMLConfig_thenMappingSuccess() {
+        String path = "D:/workspaces/Baeldung/tutorials/spring-core-4/src/test/resources/applicationcontext/account-bean-config.xml";
+
+        ApplicationContext context = new FileSystemXmlApplicationContext(path);
+        AccountService accountService = context.getBean("accountService", AccountService.class);
+
+        assertNotNull(accountService);
+        assertNotNull(accountService.getAccountRepository());
+
+        ((FileSystemXmlApplicationContext) context).close();
+    }
+
+    @Test
+    public void givenClasspathXmlAppContext_whenXMLConfig_thenMappingSuccess() {
+        ApplicationContext context = new ClassPathXmlApplicationContext("applicationcontext/account-bean-config.xml");
+        AccountService accountService = context.getBean("accountService", AccountService.class);
+
+        assertNotNull(accountService);
+        assertNotNull(accountService.getAccountRepository());
+
+        ((ClassPathXmlApplicationContext) context).close();
+    }
+
+    @Test
+    public void givenMessagesInFile_whenMessageResourceUsed_thenReadMessage() {
+        ApplicationContext context = new AnnotationConfigApplicationContext(AccountConfig.class);
+        AccountService accountService = context.getBean(AccountService.class);
+
+        assertEquals("TestAccount", accountService.getAccountName());
+
+        ((AnnotationConfigApplicationContext) context).close();
+    }
+
+}

spring-core-4/src/test/resources/applicationcontext/account-bean-config.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="
+	  http://www.springframework.org/schema/beans 
+	  http://www.springframework.org/schema/beans/spring-beans.xsd">
+	  
+	<bean id="accountService" class="com.baeldung.applicationcontext.AccountService">
+		<constructor-arg name="accountRepository" ref="accountRepository" />
+	</bean>
+	
+	<bean id="accountRepository" class="com.baeldung.applicationcontext.AccountRepository" />
+</beans>

spring-core-4/src/test/resources/applicationcontext/user-bean-config.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<beans xmlns="http://www.springframework.org/schema/beans"
+	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xmlns:context="http://www.springframework.org/schema/context"
+	xsi:schemaLocation="
+	  http://www.springframework.org/schema/beans 
+	  http://www.springframework.org/schema/beans/spring-beans.xsd 
+	  http://www.springframework.org/schema/context 
+	  http://www.springframework.org/schema/context/spring-context.xsd">
+
+	<context:annotation-config />
+	<context:component-scan
+		base-package="com.baeldung.applicationcontext" />
+
+</beans>

spring-core-4/src/test/resources/config/messages.properties

@@ -0,0 +1 @@
+account.name=TestAccount