JNLP API section in the developers guide still refer to jnlp.jar in jnlp developers bundle. but the jnlp developers bundle does not exists anymore. we should either to ask them to look for jnlp.jar in the jnlp samples directory; or use javaws.jar directly.

If you Google "JNLP BasicService" the first hit is
a document full of useful examples from Sun:
http://java.sun.com/j2se/1.4.2/docs/guide/jws/developersguide/examples.html

This page begins with an important bit of information - where
the APIs are defined:

 The public classes and interfaces in the JNLP API are included in the
 jnlp.jar file. This JAR file must be included in the classpath when
 compiling source files that use the JNLP API. ...

 The jnlp.jar file is included in the JNLP Developers Pack.

There's no link here, no information about where this "Developers
Pack" could be found. Ofcourse the alert 1.5 developer would
have noticed that this URL is for the 1.4.2 release. Since
there's been an incompatible change (now jnlp.jar is "in" the JRE)
we might have updated this page to say as much.

Except the 1.5 version of the page is worse. It not only includes
the exact same semi-helpful text; now that text is completely wrong.

And the "Enhancements to Java Web Start in J2SE 5.0" page further
confuses the situation:

http://java.sun.com/j2se/1.5.0/docs/guide/javaws/enhancements-1.5.0.html

 Elimination of Developer Bundle: Java Web Start is now fully
 integrated into the JRE and the JDK. The items which were previously
 contained in a separate developer bundle are now contained in the
 JDK. The documentation which was previously contained in the
 developers bundle is now available online. ... The JDK now also
 contains jardiff.jar, jnlp.jar, and jnlp-servlet.jar.

Except that it doesn't. Both the JRE and the JDK contain something
called javaws.jar in jre/lib. That's what you want. If you're
groveling around looking for jnlp.jar you may find
sample\jnlp\servlet\jnlp.jar.