Spring - Setter Injection with Map

In Spring, setter injection can be used to inject a Map into a bean. The Map can contain key-value pairs where both keys and values can be objects.

Let's dive into an example:

1. Java Classes:

   Let's consider a Classroom where each student (represented by name) has an associated grade.

   // Classroom.java public class Classroom { private Map<String, String> studentGrades; public void setStudentGrades(Map<String, String> studentGrades) { this.studentGrades = studentGrades; } public void displayStudentGrades() { for(Map.Entry<String, String> entry : studentGrades.entrySet()) { System.out.println("Student: " + entry.getKey() + " - Grade: " + entry.getValue()); } } } 

2. Spring XML Configuration:

   Configure the Classroom bean and its student grades using a beans.xml:

   <?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"> <!-- Classroom bean definition --> <bean id="classroomBean" class="Classroom"> <property name="studentGrades"> <map> <entry key="Alice" value="A"/> <entry key="Bob" value="B"/> <entry key="Charlie" value="C"/> </map> </property> </bean> </beans> 

   Here, we are defining a Classroom bean and using a <map> tag to inject student names as keys and their grades as values.

3. Test the Configuration:

   Create a main class to load the beans and test the configuration:

   import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class App { public static void main(String[] args) { ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml"); Classroom classroom = (Classroom) context.getBean("classroomBean"); classroom.displayStudentGrades(); } } 

   When you run this main class, it should display:

   Student: Alice - Grade: A Student: Bob - Grade: B Student: Charlie - Grade: C 

With the steps above, you can inject a Map into a Spring bean using setter injection.

Examples

1. Spring Setter Injection with Map example:

   • Description: Demonstrates how to use setter injection to inject a Map into a Spring bean.
   • Code:

     public class MyBean { private Map<String, Integer> myMap; public void setMyMap(Map<String, Integer> myMap) { this.myMap = myMap; } } 

2. Injecting a Map using Setter Injection in Spring Framework:

   • Description: Illustrates how to inject a Map using setter injection in the Spring framework.
   • Code:

     public class MyBean { private Map<String, String> myMap; public void setMyMap(Map<String, String> myMap) { this.myMap = myMap; } } 

3. Setter Injection with Map in Spring XML configuration:

   • Description: Guides on configuring setter injection with a Map in Spring XML configuration.
   • Code:

     <bean id="myBean" class="com.example.MyBean"> <property name="myMap"> <map> <entry key="key1" value="value1" /> <entry key="key2" value="value2" /> </map> </property> </bean> 

4. Spring Setter Injection for injecting a Map of dependencies:

   • Description: Demonstrates how to use setter injection to inject a map of dependencies in a Spring bean.
   • Code:

     public class MyBean { private Map<String, Dependency> dependencyMap; public void setDependencyMap(Map<String, Dependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

5. Using @Autowired with Map in Spring:

   • Description: Shows how to use @Autowired for injecting a Map in Spring using setter injection.
   • Code:

     public class MyBean { private Map<String, AnotherBean> myMap; @Autowired public void setMyMap(Map<String, AnotherBean> myMap) { this.myMap = myMap; } } 

6. Setter-based injection of Map in Spring components:

   • Description: Demonstrates setter-based injection of a Map in Spring components.
   • Code:

     @Component public class MyComponent { private Map<String, String> myMap; @Autowired public void setMyMap(Map<String, String> myMap) { this.myMap = myMap; } } 

7. Injecting a Map of values using @Value annotation in Spring:

   • Description: Shows how to use @Value annotation for injecting a map of values in Spring.
   • Code:

     public class MyBean { @Value("#{${my.map.values}}") private Map<String, String> myMap; } 

8. Configuring Setter Injection for Map in Spring Beans:

   • Description: Guides on configuring setter injection for a Map in Spring beans.
   • Code:

     @Component public class MyComponent { private Map<String, Integer> myMap; @Autowired public void setMyMap(Map<String, Integer> myMap) { this.myMap = myMap; } } 

9. Spring Setter Injection for handling key-value pairs:

   • Description: Illustrates how to use setter injection for handling key-value pairs in Spring.
   • Code:

     public class MyBean { private Properties keyValuePairs; public void setKeyValuePairs(Properties keyValuePairs) { this.keyValuePairs = keyValuePairs; } } 

10. Setter Injection with Map in Spring components:

    • Description: Demonstrates setter injection with a Map in Spring components.
    • Code:

      @Component public class MyComponent { private Map<String, AnotherComponent> myMap; @Autowired public void setMyMap(Map<String, AnotherComponent> myMap) { this.myMap = myMap; } } 

11. Using @Resource for Setter Injection with Map in Spring:

    • Description: Shows how to use @Resource for setter injection with a Map in Spring.
    • Code:

      public class MyBean { private Map<String, Dependency> dependencyMap; @Resource public void setDependencyMap(Map<String, Dependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

12. Spring Setter Injection for injecting dependencies as a Map:

    • Description: Demonstrates how to use setter injection for injecting dependencies as a map in a Spring bean.
    • Code:

      public class MyBean { private Map<String, Dependency> dependencyMap; public void setDependencyMap(Map<String, Dependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

13. Setter-based injection with autowired Map in Spring:

    • Description: Demonstrates setter-based injection with autowired Map in Spring components.
    • Code:

      @Component public class MyComponent { private Map<String, Dependency> dependencyMap; @Autowired public void setDependencyMap(Map<String, Dependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

14. Spring Setter Injection with different types of Maps:

    • Description: Illustrates how to use setter injection with different types of maps, such as HashMap, LinkedHashMap, etc., in Spring.
    • Code:

      public class MyBean { private HashMap<String, Integer> myHashMap; private LinkedHashMap<String, String> myLinkedHashMap; public void setMyHashMap(HashMap<String, Integer> myHashMap) { this.myHashMap = myHashMap; } public void setMyLinkedHashMap(LinkedHashMap<String, String> myLinkedHashMap) { this.myLinkedHashMap = myLinkedHashMap; } } 

15. Injecting properties as a Map using Setter Injection in Spring:

    • Description: Shows how to use setter injection to inject properties as a map in Spring beans.
    • Code:

      public class MyBean { private Map<String, String> propertiesMap; public void setPropertiesMap(Properties properties) { this.propertiesMap = new HashMap<>((Map) properties); } } 

16. Configuring Spring beans with Setter Injection and Map:

    • Description: Guides on configuring Spring beans with setter injection and a Map for dependencies.
    • Code:

      @Component public class MyComponent { private Map<String, Dependency> dependencyMap; @Autowired public void setDependencyMap(Map<String, Dependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

17. Spring Setter Injection with Map of dependencies:

    • Description: Demonstrates how to use setter injection with a map of dependencies in a Spring bean.
    • Code:

      public class MyBean { private Map<String, AnotherDependency> dependencyMap; public void setDependencyMap(Map<String, AnotherDependency> dependencyMap) { this.dependencyMap = dependencyMap; } } 

18. Setter Injection with Map for managing dynamic configurations in Spring:

    • Description: Shows how to use setter injection with a map for managing dynamic configurations in Spring.
    • Code:

      public class MyBean { private Map<String, String> configurationMap; public void setConfigurationMap(Map<String, String> configurationMap) { this.configurationMap = configurationMap; } } 

19. Handling maps with dependent objects in Spring Setter Injection:

    • Description: Guides on handling maps with dependent objects using setter injection in the Spring framework.
    • Code:

      public class MyBean { private Map<String, DependentObject> dependentObjectMap; public void setDependentObjectMap(Map<String, DependentObject> dependentObjectMap) { this.dependentObjectMap = dependentObjectMap; } } 

---

More Tags

intellij-idea javasound dompdf nginx-reverse-proxy cakephp-3.x maven-jaxb2-plugin double-click database-deadlocks general-network-error ngrok

More Programming Guides

• Variables in Scala
• C# Loops
• Spring Boot - EhCaching
• The eye Method in Numpy
• Perl Operators
• Ruby JSON
• Python integer type (int)
• Spring JDK Dynamic Proxy

Other Guides

• How to skip a pytest using an external fixture?
• How to make a WPF style inheritable to derived classes?
• Reading in environment variables from an environment file in python
• What is the difference between commit() and commitAllowingStateLoss() in Fragments
• How to use Activator.CreateInstance with an Interface in C#?

More Programming Examples

• javascript - How to tap on Allow button on permission pop up
• javascript - running functions one after other in react
• how to save opened page as pdf in Selenium (Python)
• windows - Batch Create a Folder Based on Filename, and Move Multiple Related Files to The Created Folder
• Android TextView display a string to three decimal places through double convertion from another class
• logstash - How to tell Elasticsearch to get the column names from the first line of a file?