How to read properties (or any other text) file in Java Spring MVC app?

Question

I need to read java properties file inside my Spring MVC app but I can't find the way to do that. I tried several answers from similar question here on SO, but I was unsuccessful. I'm new to Java, and especially Spring MVC so I probably messed up something.

I'm not sure anymore that the file is being successfully deployed. I'm using Tomcat btw.

It would be good to know your spring mvc version, do you use xml config or java, how your war looks like(if you have one) and other detail. — Admit, Oct 08 '13 at 16:25
`Properties.load(Reader)` comes to mind: http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html#load%28java.io.Reader%29 — , Oct 08 '13 at 16:28
http://stackoverflow.com/questions/2797162/getresourceasstream-is-always-returning-null — Frederic Close, Oct 08 '13 at 16:38

score 11 · Answer 1 · answered Oct 08 '13 at 18:04

11

If you are using Spring 3.1+ you can use the @PropertySource annotation:

@Configuration
@PropertySource("classpath:/com/example/app.properties")
public class AppConfig {
    // create beans
}

or for XML-based configuration you can use the <context:property-placeholder>:

<beans>
    <context:property-placeholder location="classpath:com/example/app.properties"/>
    <!-- bean declarations -->
</beans>

then you can autowire the key in the properties file using the @Value annotation:

@Value("${property.key}") String propertyValue;

Read more details in the Spring reference docs.

answered Oct 08 '13 at 18:04

matsev

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I tried doing this way. But am getting the value as null. It is not reading the value of the property. – user Sep 30 '14 at 21:05
1

Please make sure that the class that contains the `@Value` annotation is annotated with `@Component` (or any of the other component stereotype annotations). – matsev Oct 07 '14 at 12:45

gregwhitaker · Answer 2 · 2013-10-08T16:48:09.720

You can have properties files automatically loaded in Spring by using the PropertySourcesPlaceholderConfigurer.

Here is an example of configuring a PropertySourcesPlaceholderConfigurer using Spring JavaConfig:

@Bean
public static PropertySourcesPlaceholderConfigurer properties() {
    PropertySourcesPlaceholderConfigurer props = new PropertySourcesPlaceholderConfigurer();
    props.setLocations(new Resource[] {
            new ClassPathResource("/config/myconfig.properties"),
            new ClassPathResource("version.properties")
    });
}

This will load the properties from the files above on the classpath.

You can use these properties in property replacements within your application. For example, assume that there is a property in one of those files above named myprop. You could inject myprop's value into a field using the following:

@Value(${myprop})
private String someProperty;

You can also access the values of the properties by injecting Spring's Environment object into your classes.

@Resource
private Environment environment;

public void doSomething() {
   String myPropValue = environment.getProperty("myprop");
}

In order to read any old file from within a web application the link that Frederic posted in the comments above provides a good explanation of the normal classloader hurdles one encounters when attempting to read files from within their war file and the solutions around it.

score 1 · Answer 3 · answered Jan 14 '17 at 16:04

1

You can try the below code.

Add this to servelt-context.xml

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

And to access the contents of config file in java,

@Value("${KEY}")
private String value;

answered Jan 14 '17 at 16:04

Santosh Hegde

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How to read properties (or any other text) file in Java Spring MVC app?

3 Answers3