JAVA-628: Moved 3 articles to spring-di-2, added README

Author: sampadawagde

spring-di-2/README.md

@@ -0,0 +1,11 @@
+## Spring Dependency Injection
+
+This module contains articles about dependency injection with Spring
+
+### Relevant Articles
+
+- [Injecting Spring Beans into Unmanaged Objects](https://www.baeldung.com/spring-inject-bean-into-unmanaged-objects)
+- [Injecting a Value in a Static Field in Spring](https://www.baeldung.com/spring-inject-static-field)
+- [Spring – Injecting Collections](https://www.baeldung.com/spring-injecting-collections)
+- [Wiring in Spring: @Autowired, @Resource and @Inject](https://www.baeldung.com/spring-annotations-resource-inject-autowire)
+- More articles: [[<-- prev]](/spring-di)

spring-di-2/pom.xml

@@ -25,11 +25,26 @@
             <artifactId>spring-boot-starter-data-jpa</artifactId>
             <version>${spring-boot.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-web</artifactId>
+            <version>${spring-boot.version}</version>
+        </dependency>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-aspects</artifactId>
             <version>${spring.version}</version>
         </dependency>
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <version>${lombok.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>javax.inject</groupId>
+            <artifactId>javax.inject</artifactId>
+            <version>${javax.inject.version}</version>
+        </dependency>
     </dependencies>
 
     <build>
@@ -61,5 +76,6 @@
     <properties>
         <spring-boot.version>2.3.1.RELEASE</spring-boot.version>
         <aspectj-plugin.version>1.11</aspectj-plugin.version>
+        <javax.inject.version>1</javax.inject.version>
     </properties>
 </project>

spring-di-2/src/main/java/com/baeldung/collection/BaeldungBean.java

@@ -0,0 +1,18 @@
+package com.baeldung.collection;
+
+/**
+ * Created by Gebruiker on 5/22/2018.
+ */
+public class BaeldungBean {
+
+    private String name;
+
+    public BaeldungBean(String name) {
+        this.name = name;
+    }
+
+    @Override
+    public String toString() {
+        return name;
+    }
+}

spring-di-2/src/main/java/com/baeldung/collection/CollectionConfig.java

@@ -0,0 +1,50 @@
+package com.baeldung.collection;
+
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.core.annotation.Order;
+
+import java.util.*;
+
+@Configuration
+public class CollectionConfig {
+
+    @Bean
+    public CollectionsBean getCollectionsBean() {
+        return new CollectionsBean(new HashSet<>(Arrays.asList("John", "Adam", "Harry")));
+    }
+
+    @Bean
+    public List<String> nameList(){
+        return Arrays.asList("John", "Adam", "Harry", null);
+    }
+
+    @Bean
+    public Map<Integer, String> nameMap(){
+        Map<Integer, String>  nameMap = new HashMap<>();
+        nameMap.put(1, "John");
+        nameMap.put(2, "Adam");
+        nameMap.put(3, "Harry");
+        return nameMap;
+    }
+
+    @Bean
+    @Qualifier("CollectionsBean")
+    @Order(2)
+    public BaeldungBean getElement() {
+        return new BaeldungBean("John");
+    }
+
+    @Bean
+    @Order(3)
+    public BaeldungBean getAnotherElement() {
+        return new BaeldungBean("Adam");
+    }
+
+    @Bean
+    @Order(1)
+    public BaeldungBean getOneMoreElement() {
+        return new BaeldungBean("Harry");
+    }
+}

spring-di-2/src/main/java/com/baeldung/collection/CollectionInjectionDemo.java

@@ -0,0 +1,21 @@
+package com.baeldung.collection;
+
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+
+/**
+ * Created by Gebruiker on 5/18/2018.
+ */
+public class CollectionInjectionDemo {
+
+    public static void main(String[] args) {
+
+        ApplicationContext context = new AnnotationConfigApplicationContext(CollectionConfig.class);
+        CollectionsBean collectionsBean = context.getBean(CollectionsBean.class);
+        collectionsBean.printNameList();
+        collectionsBean.printNameSet();
+        collectionsBean.printNameMap();
+        collectionsBean.printBeanList();
+        collectionsBean.printNameListWithDefaults();
+    }
+}

spring-di-2/src/main/java/com/baeldung/collection/CollectionsBean.java

@@ -0,0 +1,62 @@
+package com.baeldung.collection;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Qualifier;
+import org.springframework.beans.factory.annotation.Value;
+
+/**
+ * Created by Gebruiker on 5/18/2018.
+ */
+public class CollectionsBean {
+
+    @Autowired
+    private List<String> nameList;
+
+    private Set<String> nameSet;
+
+    private Map<Integer, String> nameMap;
+
+    @Autowired(required = false)
+    @Qualifier("CollectionsBean")
+    private List<BaeldungBean> beanList = new ArrayList<>();
+
+    @Value("${names.list:}#{T(java.util.Collections).emptyList()}")
+    private List<String> nameListWithDefaultValue;
+    
+    public CollectionsBean() {
+    }
+
+    public CollectionsBean(Set<String> strings) {
+        this.nameSet = strings;
+    }
+
+    @Autowired
+    public void setNameMap(Map<Integer, String> nameMap) {
+        this.nameMap = nameMap;
+    }
+
+    public void printNameList() {
+        System.out.println(nameList);
+    }
+
+    public void printNameSet() {
+        System.out.println(nameSet);
+    }
+
+    public void printNameMap() {
+        System.out.println(nameMap);
+    }
+
+    public void printBeanList() {
+        System.out.println(beanList);
+    }
+    
+    public void printNameListWithDefaults() {
+        System.out.println(nameListWithDefaultValue);
+    }
+}

spring-di-2/src/main/java/com/baeldung/dependency/AnotherArbitraryDependency.java

@@ -0,0 +1,13 @@
+package com.baeldung.dependency;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class AnotherArbitraryDependency extends ArbitraryDependency {
+
+    private final String label = "Another Arbitrary Dependency";
+
+    public String toString() {
+        return label;
+    }
+}

spring-di-2/src/main/java/com/baeldung/dependency/ArbitraryDependency.java

@@ -0,0 +1,13 @@
+package com.baeldung.dependency;
+
+import org.springframework.stereotype.Component;
+
+@Component(value = "autowiredFieldDependency")
+public class ArbitraryDependency {
+
+    private final String label = "Arbitrary Dependency";
+
+    public String toString() {
+        return label;
+    }
+}

spring-di-2/src/main/java/com/baeldung/dependency/YetAnotherArbitraryDependency.java

@@ -0,0 +1,13 @@
+package com.baeldung.dependency;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class YetAnotherArbitraryDependency extends ArbitraryDependency {
+
+    private final String label = "Yet Another Arbitrary Dependency";
+
+    public String toString() {
+        return label;
+    }
+}

spring-di-2/src/main/java/com/baeldung/staticvalue/injection/Application.java

@@ -0,0 +1,17 @@
+package com.baeldung.staticvalue.injection;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.jdbc.DataSourceAutoConfiguration;
+import org.springframework.context.annotation.PropertySource;
+
+@SpringBootApplication(exclude={DataSourceAutoConfiguration.class})
+@PropertySource("/application.properties")
+
+public class Application {
+
+	public static void main(String[] args) {
+		SpringApplication.run(Application.class, args);
+	}
+
+}

spring-di-2/src/main/java/com/baeldung/staticvalue/injection/PropertyController.java

@@ -0,0 +1,30 @@
+package com.baeldung.staticvalue.injection;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import java.util.Arrays;
+import java.util.List;
+
+@RestController
+public class PropertyController {
+
+    @Value("${name}")
+    private String name;
+
+    @Value("${name}")
+    private static String NAME_NULL;
+
+    private static String NAME_STATIC;
+
+    @Value("${name}")
+    public void setNameStatic(String name){
+        PropertyController.NAME_STATIC = name;
+    }
+
+    @GetMapping("/properties")
+    public List<String> getProperties(){
+        return Arrays.asList(this.name, NAME_STATIC, NAME_NULL)  ;
+    }
+}

spring-di-2/src/main/resources/application.properties

@@ -0,0 +1 @@
+name = Inject a value to a static field

spring-di-2/src/test/java/com/baeldung/wiring/configuration/ApplicationContextTestAutowiredName.java

@@ -0,0 +1,9 @@
+package com.baeldung.wiring.configuration;
+
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan(basePackages = {"com.baeldung.dependency"})
+public class ApplicationContextTestAutowiredName {
+}

spring-di-2/src/test/java/com/baeldung/wiring/configuration/ApplicationContextTestAutowiredQualifier.java

@@ -0,0 +1,25 @@
+package com.baeldung.wiring.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.baeldung.dependency.AnotherArbitraryDependency;
+import com.baeldung.dependency.ArbitraryDependency;
+
+@Configuration
+public class ApplicationContextTestAutowiredQualifier {
+
+    @Bean
+    public ArbitraryDependency autowiredFieldDependency() {
+        ArbitraryDependency autowiredFieldDependency = new ArbitraryDependency();
+
+        return autowiredFieldDependency;
+    }
+
+    @Bean
+    public ArbitraryDependency anotherAutowiredFieldDependency() {
+        ArbitraryDependency anotherAutowiredFieldDependency = new AnotherArbitraryDependency();
+
+        return anotherAutowiredFieldDependency;
+    }
+}

spring-di-2/src/test/java/com/baeldung/wiring/configuration/ApplicationContextTestAutowiredType.java

@@ -0,0 +1,16 @@
+package com.baeldung.wiring.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.baeldung.dependency.ArbitraryDependency;
+
+@Configuration
+public class ApplicationContextTestAutowiredType {
+
+    @Bean
+    public ArbitraryDependency autowiredFieldDependency() {
+        ArbitraryDependency autowiredFieldDependency = new ArbitraryDependency();
+        return autowiredFieldDependency;
+    }
+}

spring-di-2/src/test/java/com/baeldung/wiring/configuration/ApplicationContextTestInjectName.java

@@ -0,0 +1,17 @@
+package com.baeldung.wiring.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.baeldung.dependency.ArbitraryDependency;
+import com.baeldung.dependency.YetAnotherArbitraryDependency;
+
+@Configuration
+public class ApplicationContextTestInjectName {
+
+    @Bean
+    public ArbitraryDependency yetAnotherFieldInjectDependency() {
+        ArbitraryDependency yetAnotherFieldInjectDependency = new YetAnotherArbitraryDependency();
+        return yetAnotherFieldInjectDependency;
+    }
+}

spring-di-2/src/test/java/com/baeldung/wiring/configuration/ApplicationContextTestInjectQualifier.java

@@ -0,0 +1,23 @@
+package com.baeldung.wiring.configuration;
+
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import com.baeldung.dependency.AnotherArbitraryDependency;
+import com.baeldung.dependency.ArbitraryDependency;
+
+@Configuration
+public class ApplicationContextTestInjectQualifier {
+
+    @Bean
+    public ArbitraryDependency defaultFile() {
+        ArbitraryDependency defaultFile = new ArbitraryDependency();
+        return defaultFile;
+    }
+
+    @Bean
+    public ArbitraryDependency namedFile() {
+        ArbitraryDependency namedFile = new AnotherArbitraryDependency();
+        return namedFile;
+    }
+}