Dependency injection pattern with XML-based configuration

Spring provides dependency injection with XML-based configuration from the very beginning. It is the primary way of configuring a Spring application. According to me, every developer should have an understanding of how to use XML with a Spring application. In this section, I am going to explain the same example as discussed in the previous section of Java-based configuration with reference to XML-based configuration.

 

Creating an XML configuration file

In the section on Java-based configuration, we had created an AppConfig class annotated with the @Configuration annotation. Similarly, for XML-based configuration, we will now create an applicationContext.xml file rooted with a <beans> element. The following simplest possible example shows the basic structure of XML-based configuration metadata:

Following is the applicationContext.xml file:

    <?xml version="1.0" encoding="UTF-8"?> 
    <beans xmlns="http://www.springframework...