Question

I need to write a web-aplication that connects to database and reads connections properties from .properties file.
I use Maven and I want to write some unit test for my app.
To test classes that works with database I put my .properties file to src/main/resources and to test/main/resources and wrote the following code for reading properties:

package util;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
import org.apache.log4j.Logger;


/**
 *
 * @author proger
 */
public class ProgrammSettings {

    private static Logger logger = Logger.getRootLogger();
    private static String propertiesPath = "program.settings.properties";

    private static Properties props;

    public static String getProperty(String key) {
        if (props == null)
            loadProperties();

       return props.getProperty(key);

    }

    public static void setResourcesFilePath(String path) {
        propertiesPath = path;
    }

    private static void loadProperties() {
        InputStream propOut = null;
        try {
            //URL url =  ClassLoader.getSystemResource(propertiesPath);
            propOut = ClassLoader.getSystemClassLoader().getResourceAsStream(propertiesPath); //new FileInputStream(url.getFile());
            props = new Properties();
            props.load(propOut);
        } catch (Exception ex) {
            //Logger.getLogger(ProgrammSettings.class.getName()).log(Level.SEVERE, null, ex);
            String errorMessage = "Error during properties file reading. Path to file: '" +
                           propertiesPath + "'";
            logger.error(errorMessage, ex);
            throw new RuntimeException(errorMessage, ex);
        } finally {
            try {
                if (propOut != null)
                    propOut.close();
            } catch (IOException ex) {
                logger.error("Error during closing stream from properties file", ex);
            }
        }
    }
}

I wanted the same code worked both for tests and app classes, so I read properties file from classPath.
All my tests pass and my .properties file is packed into war by Maven. But when I run my App from Netbeans this I receive:

java.lang.NullPointerException
    java.util.Properties$LineReader.readLine(Properties.java:435)
    java.util.Properties.load0(Properties.java:354)
    java.util.Properties.load(Properties.java:342)
    util.ProgrammSettings.loadProperties(ProgrammSettings.java:49)
    util.ProgrammSettings.getProperty(ProgrammSettings.java:33)
    dataacess.AbstractDataMapper.loadDriver(AbstractDataMapper.java:58)
    dataacess.AbstractDataMapper.<init>(AbstractDataMapper.java:41)
    dataacess.UserMapper.<init>(UserMapper.java:25)
    servlets.UserRegistration.processRequest(UserRegistration.java:86)
    servlets.UserRegistration.doPost(UserRegistration.java:132)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:637)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    org.netbeans.modules.web.monitor.server.MonitorFilter.doFilter(MonitorFilter.java:393)

How can I fix it? Thank you in advance

Answer 1

Place program.settings.properties in webapps/appname/WEB-INF/classes

And you can use a simpler line ProgrammSettings.class.getResourceAsStream(..) (i.e. not the system classloader, but the current classloader)