MP3 Encoding in Java

The LAME4J uses the free but time-limited license and the unlimited license will cost you some money.

I've found the Lamejb library on the SourceForge, which requires only the lame binaries and works well without any additional licensing.

Is has been some time, but Oracle/Sun has released MP3 support for JMF. This can be downloaded from the following url: http://www.oracle.com/technetwork/java/javase/tech/index-jsp-140239.html

Adding it to the classpath will enable playback via the AudioSystem api.

Use the Process API to invoke SoX

SoX comes with source or as precompiled binaries for Windows and Mac.

There may not be an adequate answer for you, yet, as the MP3 format requires the authors of decoder/encoders to obtain a license from the Fraunhofer Institute.

I think the the LAME library is distributed from a country that does not respect these IP issues, but it took a considerably amount of legal hackery to get this far.

For any other libraries - for example one written in Java, the authors need to get a similar license. Where cost is an issue - e.g. in an Open Source project, then this is enough of a disincentive to starting.

For more details see this wikipedia article.

If LAME4J is not stable enough for you, then I'm afraid your options are probably:

• wait for Sun to license the format for the core JRE. This, I believe they have done recently, but I don't know of any release dates (perhaps to do with JavaFX)
• implement your own in Java, and pay the license. I wouldn't fancy this one, either.
• write your own Java wrapper to LAME, via JNA, or SWIG
• contribute to Lame4J.
• pick another format. OGG and FLAC are quite good, and relatively well supported.