How to get the property value inside a spring bean class in my class ?

Question

The things I did are:

• Created a property file (data.properties).
• Created a Spring.xml (I use property placeholder)
• Created a bean class.
• I have a class where I have to use the url value.
• I have a web.xml which has context-param where i set the param value to the path of the Spring.xml file.
• My codes are given below:

Propertyfile:url=sampleurl

Spring.xml:

<bean
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="locations" value="classpath*:data.properties*"/>

</bean>

<bean id="dataSource" class="org.tempuri.DataBeanClass">
    <property name="url" value="${url}"></property>
</bean>

beanclass

public class DataBeanClass extends PropertyPlaceholderConfigurer{
private String url;

public String getUrl() {
    return url;
}

public void setUrl(String url) {
    this.url = url;
}
}

entry in web.xml

 <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath*:Spring*.xml</param-value>
</context-param>
<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

Now my problem is I dont know what method of PropertyPlaceholderConfigurer should I override and what should I do to set the value of variable url such that I can call it from other classes using getproperty() method.

Answer 1

Please do the following process to get property file value in class.

1. Define the bean for property file in your spring.xml
   <util:properties id="dataProperties" location="classpath:/data.properties"/>

2. keep your data.properties under src/main/resources.

3. Use the following code to get value from property file for e.g to get value of url key in data.properties

private @Value("#{dataProperties['url']})
String url;

Answer 2

Properties files can be made accessible to Spring via the following namespace element in Spring.xml

<context:property-placeholder location="classpath:data.properties" />

And then you can use like

@Autowired
private Environment env;
...
String url=env.getProperty("url"));

Note:

using <property-placeholder> will not expose the properties to the Spring Environment – this means that retrieving the value like this will not work – it will return null

Answer 3

You can annotate your bean property like this, then spring will auto inject the property from your property file.

@Value("${url}")
private String url;

You dont have to extend PropertyPlaceholderConfigurer

Defining your bean like this will auto populate url as well, but annotation seems to be easiest way

<bean id="dataSource" class="org.tempuri.DataBeanClass">
   <property name="url" value="${url}"></property>
</bean>