@ImportResource not working

Question

I am new to Spring boot and I want to implement simple web application which renders UI using some Mustache templates.

I have written some Spring components (controllers,DAO,Services) whose package structure is different (not falling under same or sub directory as Spring boor runner class). So I am using @ImportResource annotation to declare spring configuration. But my application is not reading any configuration files.

Please refer below code snippet for more details

1. Project Structure :

Here not that, Spring boot application launcher classes written in package SpringPropertyReaderApplication.

ApplicationConfiguration class is written under same hierarchical package structure which defined few more configuration using @ImportResource annotation.

2. Spring boot application launcher class.

package com.example.launcher;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;

@SpringBootApplication
public class SpringPropertyReaderApplication {

  public static void main(String[] args) {


      ApplicationContext applicationContext = SpringApplication.run(SpringPropertyReaderApplication.class, args);

      System.out.println("------------------------------------------------");
      System.out.println("-----Printing Bean Definition Names ------------");
      System.out.println("------------------------------------------------");
      for (String name : applicationContext.getBeanDefinitionNames()) {
          System.out.println(name);
      }
      System.out.println("------------------------------------------------");
      System.out.println("--------------------END------------------------");
      System.out.println("------------------------------------------------");
  }
}

3. ApplicationConfiguration class where I have shared location of other Spring configuration files.

package com.example.launcher.configuration;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportResource;

@Configuration
@ImportResource(locations = {"classpath*:application-context.xml"})
public class ApplicationConfiguration {

  @Bean
  public String someDummyBean1() {
      return "someDummyBean1";
  }
}

4. Spring Application configuration which is not getting loaded by the container.

Here, I have added component scan annotation to scan my services and controllers which were not in the same package as Spring launcher class.

<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-2.5.xsd
  http://www.springframework.org/schema/context
  http://www.springframework.org/schema/context/spring-context-2.5.xsd">


  <context:component-scan
      base-package="com.example" />

  <bean id="xmlStringBean1" class="java.lang.String">
      <constructor-arg value="stringBean1" />
  </bean>

</beans>

I have added code to log of all bean names which are loaded by Spring boot. But I did not find any bean with name "xmlStringBean1" and "myController".

Also note that, this application works fine If i put my Rest controller and other classes under the same package hierarchy as Spring boot launcher class.

Answer 1

Since, application-context.xml resides inside the spring folder under src/main/resources. But the @ImportResource annotation defined in ApplicationConfiguration.java tries to scan it just inside the root path. Hence, the file was not detected.

@ImportResource(locations = {"classpath*:application-context.xml"})

to be replaced with

@ImportResource(locations = {"classpath:spring/application-context.xml"}) . 

This will enforce framework to search for application-context.xml inside spring directory (starting from root level).

Answer 2

I think your spring boot application is not detecting the class annotated with @Configuration, because by default it will try to find the Configuration classes in the same or child packages as the main class. Annotate your SpringPropertyReaderApplication with @ComponentScan, like this:

@SpringBootApplication
@ComponentScan(basePackageClasses = {ApplicationConfiguration.class})
public class SpringPropertyReaderApplication {
    // your code here
}