如何从Maven项目中的外部jar读取属性文件

Question

I am new to maven and Java . I am working on a large codebase which uses the Spring web framework. I may be missing fundamentals but I have done my best to go over all the basics of the project implementation.
For the feature I am building,I have properties files that I had earlier saved in src/main/resources in my maven project and was reading from my class named ReaderClass with this statement

ReaderClass.class.getResourceasStream("xyz.properties");

Now I have externalized these files into a separate project and have built a jar out of it. This jar only has the properties files under a folder named resource.
I have added this jar file as an dependency in the IntelliJ IDE and would like to read the properties files from this jar. Had it been a .class file I would use an import statement in ReaderClass but how would I read properties files?

ADDITIONAL INFORMATION

Also, I am not sure if this is a problem but IntelliJ doesn't actually show the jar in the External Libraries Tab but does show my jar in the dependencies tab of the Modules Section in Project Structure. I wanted to make sure this wouldn't affect the solution.

Answer 1

If you are using Spring, try

@Value("${property.name}")
private String property;

to read properties from resources folder.

Answer 2

There are numerous ways to do this.

Assuming your xyz.properties file looks like this:

a=b
y=z
mykey=myvalue

Using java.util.ResourceBundle

If you don't need to pass around the read data as a Properties object, this is the easiest way.

ResourceBundle rb = ResourceBundle.getBundle("xyz");
System.out.println("a=" + rb.getString("a"));

Using java.util.Properties

A bit more work and some boiler-plate, but accomplishes the same thing.

Properties p = new Properties();
try (InputStream is = getClass().getClassLoader().getResourceAsStream("xyz.properties")) {
   p.load(is);
}
catch (IOException e) {
   // Handle as appropriately.
}
System.out.println("mykey=" + p.getProperty("mykey"));