public class ReadProperties{

    private static String proFileName = "/config/MQSubjectId.properties";

    private static Properties pro;  

    static{

        try {

            pro = new Properties();

            InputStream in = ClassLoader.class.getResourceAsStream(proFileName);

            pro.load(in);

            in.close();

        } catch (IOException e) {

            e.printStackTrace();

        }

    } 
}

import java.util.Properties;

public class SystemVar {

    private static Properties cache = new Properties();

    static {

        try {

            cache.load(ClassLoader.class.getResourceAsStream("/config/systemConfig.properties"));

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

    public static String getValue(String key){

        return cache.getProperty(key);

    }

    public static void main(String[] args) {

        System.out.println(getValue("environment"));

    }

}