How to make Component Plugin Module dependency-injected.

1. Write the below in the atlassian-plugin.xml.

<component key="helloWorldService" public="true" class="com.akira.MyHelloWorldServiceImpl">
<interface>com.akira.MyHelloWorldService</interface>
</component>

2. MyHelloWorldService

package com.akira;

public interface MyHelloWorldService {
String getMessage();
}

3. MyHelloWorldServiceImpl

package com.akira;

public class MyHelloWorldServiceImpl implements MyHelloWorldService {

public String getMessage() {
return "Hello World";
}
}

4. Use the Component Plugin Module in an ActionSupport class.

public class AkiraActionSupport extends JiraWebActionSupport {

private MyHelloWorldService _myHelloWorldService;

public String doExecute() {
System.out.println(_myHelloWorldService.getMessage());
return SUCCESS;
}
}

5. A NullPointerException occurs because the dependency-injection fails.

6. What other steps are required to make Componet Module available.