Recipe : How to get property value in a Spring Application

If you work with Spring, I am sure you might have come across the scenario when you need to access the value of a property key in your application.

The class "org.springframework.beans.factory.config.PropertyPlaceholderConfigurer" is normally used to resolve the runtime key/value pairs. However, if you need to use a property value in your bean, it doesn't expose that to be read.

Here is a very simple work-around :-

1. Extend the PropertyPlaceholderConfigurer

public class OpenPropertyPlaceholderConfigurer extends PropertyPlaceholderConfigurer {

  Properties mergedProperties;

  public Properties getMergedProperties() throws IOException {
    if (mergedProperties == null) {

      mergedProperties = mergeProperties();

    }
    return mergedProperties;

  }
}

2. Configure it to be used instead of PropertyPlaceholderConfigurer

  
  <bean id="propertyConfigurer" class="com.mypackage.OpenPropertyPlaceholderConfigurer">
        <property name="ignoreResourceNotFound" value="false"/>
        <property name="locations">
            <list>
                <value>classpath:common.properties</value>
                <value>classpath:${YOUR_ENV}.properties</value>
            </list>
        </property>
    </bean>

3. Inject this "propertyConfigurer" in your defined bean.

4. Get the key value propertyConfigurer.getMergedProperties().getProperty("your.prop.key")

I am sure, there could be some better ways. Let me know, if you know one.

Credit goes to Mat for this recipe.