java - Injecting Properties using Spring & annotation @Value

Question

I am trying to load a properties file into a Spring bean and then inject that bean into a class.

The only part I can't get to work seems to be using the @Resource reference.Can someone connect the last piece for me? I get a null value every time. Doesn't seem to want to inject the value.

[EDIT] - I originally thought using the @Resource was the best way but the proposed solution I found easier.

I saw this solution in another post:

Reference Solution Link: Inject Property Value into Spring - posted by DON

Credit to Don for the post but I just wasn't sure how to finish it with the @Resource.

Debugging Results: The variable value appProperties is always null. It's not being injected.

Spring Config.

Sample Class:

package test;

import java.util.Properties;
import javax.annotation.Resource;


public class foo {
    public foo() {}
    @Resource private java.util.Properties appProperties;
}

Based on the advice in the approved solution below. Here are the changes I made.

---

Solution Update:

Spring Config:

Java Class:

Answer 1

For your solution to work you would also need to make foo a Spring managed bean; because otherwise how would Spring know that it has to deal with any of your annotations on your class?

• You can either specify it in your appcontext xml as a bean with ..class="foo"
• Or use component-scan and specify a base package which contains your foo class.

Since I'm not entirely sure this is exactly what you want (don't you want a .properties file to be parsed by Spring and have it's key-value pairs available instead of a Properties object?), I'm suggesting you another solution: Using the util namespace

<util:properties id="props" location="classpath:com/foo/bar/props.properties"/>

And reference the values inside your beans (also, have to be Spring managed):

@Value("#{props.foo}")
public void setFoo(String foo) {
    this.foo = foo;
}

EDIT:

just realized that you are importing org.springframework.context.ApplicationContext in your class which is probably unnecessary. I strongly encourage you to read Spring reference at least the first few chapters, because a) it's a great read b) you will find it much easier to understand Spring if the basics are clear.