Question

I am trying to load a property file in Java in static initialization code:

public class NFWConfiguration {

private static final Properties PROPS = new Properties();

static {
    try {

        InputStream IS = NFWConfiguration.class.getClassLoader()
            .getResourceAsStream(
                "/net/nfw/Configuration/NFWConfiguration.properties");

        PROPS.load(IS);

    } catch (IOException ex) {
        Logger.getLogger(NFWConfiguration.class.getName())
            .log(Level.SEVERE, null, ex);
    }
}

    // ...

}

Yet, I get the following error message:

Caused by: java.lang.NullPointerException
at java.util.Properties$LineReader.readLine(Properties.java:418)
at java.util.Properties.load0(Properties.java:337)
at java.util.Properties.load(Properties.java:325)
at net.nfw.Configuration.NFWConfiguration.<clinit>(NFWConfiguration.java:28)

Indeed IS is null, but it has no reason to be null. I have double-checked in the .jar, and the property file is there in the right directory.

What am I doing wrong?

Answer 1

Try after removing the leading / in the path as:

      InputStream IS = NFWConfiguration.class.getClassLoader()
        .getResourceAsStream(
            "net/nfw/Configuration/NFWConfiguration.properties");