Why wont my added SPI jars register in my Netbeans Platform project?

Question

In Netbeans 8.0 I have a project with multiple modules. I want one module to open a file chooser for audio files that the app will play using javax.sound.sampled library. I use AudioSystem.getAudioFileTypes() to get the file types that can be used and see that there are only 3 available ('wav', 'au' and 'aif') but I'd also like to be able to deal with mp3, ogg and flac.

So I downloaded the SPIs for the codecs I need. All the documentation tells me that I need only put the jars into the classpath and the codecs will become available to Java's sound library. In my project I want more than one module to be able to use these libraries, so I created module wrappers for them. So, for example, I have in my project one module called jflac-1.3-jdk which wraps two jars: jflac-1.3-jdk1.4.jar and jflac-1.3.jar then I make the module that is going to open the file chooser depend on these modules that wrap jars.

Still there are only the same 3 file types available. What am I missing?

Here is the code in the top component of the module that depends on the wrapper modules:

private static String[] audioFileExtensions;
static
{
    AudioFileFormat.Type[] formatTypes = AudioSystem.getAudioFileTypes();
    audioFileExtensions = new String[formatTypes.length];
    for (int i = 0; i < formatTypes.length; i++) {
        audioFileExtensions[i] = formatTypes[i].getExtension();
    }
}

I use the debugger in this code to see that the file types I want aren't available.

Answer 1

The SPIs should be registered using the ServiceLoader mechanism, which the jars you downloaded don't seem to do. That is probably a bug in their packaging.

I have never used jflac, but it looks like you should register:

• org.kc7bfi.jflac.sound.spi.FlacAudioFileReader as a javax.sound.sampled.spi.AudioFileReader and
• org.kc7bfi.jflac.sound.spi.FlacFormatConversionProvider as a javax.sound.sampled.spi.FormatConversionProvider.

The source repository actually contains the necessary service files. Add these to your resources under META-INF/services.