Merge pull request #8346 from albanoj2/BAEL-3290

BAEL-3290: Added source code for Spring DI examples

spring-di/src/main/java/org/baeldung/store/AppConfig.java

@@ -0,0 +1,23 @@
+package org.baeldung.store;
+
+import org.springframework.context.annotation.Bean;
+
+public class AppConfig {
+
+    @Bean
+    public Item item1() {
+        return new ItemImpl1();
+    }
+ 
+    @Bean
+    public Store storeThroughConstructorInjection() {
+        return new Store(item1());
+    }
+    
+    @Bean
+    public Store storeThroughSetterInjection() {
+        Store store = new Store();
+        store.setItem(item1());
+        return store;
+    }
+}

spring-di/src/main/java/org/baeldung/store/Item.java

@@ -0,0 +1,5 @@
+package org.baeldung.store;
+
+public interface Item {
+
+}

spring-di/src/main/java/org/baeldung/store/ItemImpl1.java

@@ -0,0 +1,5 @@
+package org.baeldung.store;
+
+public class ItemImpl1 implements Item {
+
+}

spring-di/src/main/java/org/baeldung/store/Store.java

@@ -0,0 +1,23 @@
+package org.baeldung.store;
+
+import org.springframework.beans.factory.annotation.Autowired;
+
+public class Store {
+    
+    @Autowired
+    private Item item;
+    
+    public Store() {}
+    
+    public Store(Item item) {
+        this.item = item;
+    }
+
+    public Item getItem() {
+        return item;
+    }
+
+    public void setItem(Item item) {
+        this.item = item;
+    }
+}

spring-di/src/main/resources/ioc-context-by-type.xml

@@ -0,0 +1,14 @@
+<?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-3.0.xsd">
+    
+	<!-- Autowired injection -->
+
+    <bean id="item" class="org.baeldung.store.ItemImpl1" />
+	
+    <bean id="xml-store-by-autowire-type" class="org.baeldung.store.Store" autowire="byType">
+    </bean>
+
+</beans>

spring-di/src/main/resources/ioc-context.xml

@@ -0,0 +1,34 @@
+<?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-3.0.xsd">
+    
+    <!-- Constructor injection -->
+
+    <bean id="item1" class="org.baeldung.store.ItemImpl1" />
+    <bean id="xml-store-by-constructor" class="org.baeldung.store.Store">
+        <constructor-arg type="Item" index="0"    name="item" ref="item1" />
+    </bean>
+    
+    <!-- Setter injection -->
+
+    <bean id="xml-store-by-setter" class="org.baeldung.store.Store">
+        <property name="item" ref="item1" />
+    </bean>
+    
+    <!-- Autowired injection -->
+    
+    <bean id="item" class="org.baeldung.store.ItemImpl1" />
+
+    <bean id="xml-store-by-autowire-name" class="org.baeldung.store.Store" autowire="byName">
+    </bean>
+    
+    <!-- Lazy instantiation -->
+    
+    <bean id="item1-lazy" class="org.baeldung.store.ItemImpl1" lazy-init="true" />
+    <bean id="xml-store-by-setter-lazy" class="org.baeldung.store.Store">
+        <property name="item" ref="item1-lazy" />
+    </bean>
+
+</beans>

spring-di/src/test/java/org/baeldung/store/AppConfigUnitTest.java

@@ -0,0 +1,35 @@
+package org.baeldung.store;
+
+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.beans.factory.annotation.Qualifier;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration(classes = AppConfig.class)
+public class AppConfigUnitTest {
+
+    @Autowired
+    @Qualifier("storeThroughConstructorInjection")
+    private Store storeByConstructorInjection;
+    
+    @Autowired
+    @Qualifier("storeThroughSetterInjection")
+    private Store storeBySetterInjection;
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreByConstructorInjection_ThenBeanIsNotNull() {
+        assertNotNull(storeByConstructorInjection);
+        assertNotNull(storeByConstructorInjection.getItem());
+    }
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreBySetterInjection_ThenBeanIsNotNull() {
+        assertNotNull(storeBySetterInjection);
+        assertNotNull(storeByConstructorInjection.getItem());
+    }
+}

spring-di/src/test/java/org/baeldung/store/XmlAppConfigByTypeUnitTest.java

@@ -0,0 +1,30 @@
+package org.baeldung.store;
+
+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.beans.factory.annotation.Qualifier;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+/**
+ * Separate unit test class where only one Item object is available for 
+ * autowiring. If the ioc-context.xml were used for autowiring by type, there 
+ * would be multiple qualifying Item objects, causing a failure.
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:/ioc-context-by-type.xml")
+public class XmlAppConfigByTypeUnitTest {
+
+    @Autowired
+    @Qualifier("xml-store-by-autowire-type")
+    private Store storeByAutowireInjectionByType;
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreByAutowireInjectionByType_ThenBeanIsNotNull() {
+        assertNotNull(storeByAutowireInjectionByType);
+        assertNotNull(storeByAutowireInjectionByType.getItem());
+    }
+}

spring-di/src/test/java/org/baeldung/store/XmlAppConfigUnitTest.java

@@ -0,0 +1,55 @@
+package org.baeldung.store;
+
+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.beans.factory.annotation.Qualifier;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@ContextConfiguration("classpath:/ioc-context.xml")
+public class XmlAppConfigUnitTest {
+    
+    @Autowired
+    @Qualifier("xml-store-by-constructor")
+    private Store storeByConstructorInjection;
+    
+    @Autowired
+    @Qualifier("xml-store-by-setter")
+    private Store storeBySetterInjection;
+
+    @Autowired
+    @Qualifier("xml-store-by-autowire-name")
+    private Store storeByAutowireInjectionByName;
+    
+    @Autowired
+    @Qualifier("xml-store-by-setter-lazy")
+    private Store storeBySetterInjectionLazy;
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreByConstructorInjection_ThenBeanIsNotNull() {
+        assertNotNull(storeByConstructorInjection);
+        assertNotNull(storeByConstructorInjection.getItem());
+    }
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreBySetterInjection_ThenBeanIsNotNull() {
+        assertNotNull(storeBySetterInjection);
+        assertNotNull(storeByConstructorInjection.getItem());
+    }
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreByAutowireInjectionByName_ThenBeanIsNotNull() {
+        assertNotNull(storeByAutowireInjectionByName);
+        assertNotNull(storeByAutowireInjectionByName.getItem());
+    }
+
+    @Test
+    public void givenValidXmlConfig_WhenInjectStoreBySetterInjectionLazy_ThenBeanIsNotNull() {
+        assertNotNull(storeBySetterInjectionLazy);
+        assertNotNull(storeByConstructorInjection.getItem());
+    }
+}