将外部属性文件添加到类路径

Question

My application is packaged into a jar file and is run with the regular "java -jar ..." command.

I have a properties file "myApp.properties" in the directory: /opt/myuser/resources

I want to add the /opt/myuser/resources directory to the classpath. I believe this is advantageous because when the properties files are on the classpath, I can access the properties files in my source code without specifying the full path to the properties files (/opt/myuser/resources/myApp.properties). This way I can keep a properties file with environment-specific properties separate from my application.

I've tried to set the classpath using instructions from Oracle ( http://docs.oracle.com/javase/7/docs/technotes/tools/solaris/classpath.html under "Using the JDK tools' -classpath option") like this:

java -cp .:/opt/myuser/resources -jar myApp.jar

but I get an error that the properties file myApp.properties (referenced in the source code) cannot be opened:

Caused by: java.io.FileNotFoundException: class path resource [myApp.properties] cannot be opened because it does not exist

Am I going about this the wrong way? Should I edit the classpath in another way?

Answer 1

Hopefully this will help someone else. I've used as program arguments for spring boot --spring.config.location=file:/opt/myuser/resources/myApp.properties

and then it will use that file.

Answer 2

use gerResource solutions to load file on your Properties Object:

  ClassLoader.getResourceAsStream ("some/pkg/resource.properties");
  Class.getResourceAsStream ("/some/pkg/resource.properties");
  ResourceBundle.getBundle ("some.pkg.resource");