<p>I need to compress portions of our application's network traffic for performance.  I presume this means I need to stay away from some of the newer algorithms like bzip2, which I think I have heard is slower.</p>

You can use
Deflater
/
Inflater
which is built into the JDK.  There are also GZIPInputStream and GZIPOutputStream, but it really depends on your exact use.
Edit:
Reading further comments it looks like the network taffic is HTTP.  Depending on the server, it probably has support for compression (especially with deflate/gzip).  The problem then becomes on the client.  If the client is a browser it probably already supports it.  If your client is a webservices client or an
http client
check the documentation for that package to see if it is supported.
It looks like jakarta-commons httpclient may require you to manually do the compression.  To enable this on the client side you will need to do something like
```
```
.addRequestHeader("Accept-Encoding","gzip,deflate");
```
```