Question

I have been able to get resources to load in both Netbeans and a JAR file, such as ImageIcons, but today I am unable to “read” from same directory when running my program from a JAR file. I want to list the directories and files in a classpath directory, but when I run the program from a JAR file the directory becomes unreadable. It works fine in Netbeans.

tileDirectory = new File(TileDirectoryLister.class.getResource("/resources/images/tiles").getPath());

    jta.append("\nThe class path for the tile directory is:"
            + "\n\t" + tileDirectory.getPath());

    jta.append("\nThe tile directory is readable: " + tileDirectory.canRead());

When run from Netbeans it prints true; when run from a JAR file it prints false. Why does canRead print false when I run from a JAR file?

Answer 1

A File represents a path on the file system. Your icons are inside a jar file. You can’t use a File to access them.

To get access to some resource in the jar file, just use

SomeClass.class.getResourceAsStream("/resources/images/tiles/SomeIcon.png");

to get an InputStream, or

SomeClass.class.getResource("/resources/images/tiles/SomeIcon.png");

to get a URL.