Can I use an Environment variable based location for Spring FileSystemResource?

Question

I have a requirement to have all our properties files be stored in a directory. The location of this directory should be stored in a system environment variable. In my appli

Answer 1

Example:

Start you app with -DDA_HOME=c:\temp

c:\temp must contain directory called "config"

In c:\temp\config you have file app.properties (for example)

Extend the Spring loader:

public class Loader extends org.springframework.beans.factory.config.PropertyPlaceholderConfigurer{

    private String appHome;

    public void setAppHome(String appHome) {
        this.appHome = appHome;
    }

    @Override
    public void setLocation(Resource location) {
        if(appHome==null){
            throw new RuntimeException("You must specify VM property DA_HOME, this directory must contain " +
                    "another directory, called config, inside the config directory app.properties " +
                    "file must be found with the configuration properties");
        }
        String configurationDirectory = appHome + System.getProperty("file.separator") + "config";
        String fileName = location.getFilename();
        Resource file = new FileSystemResource( configurationDirectory + System.getProperty("file.separator")+ fileName);
        super.setLocation(file);
    }
}

Specify the new loader and its configuration base: