The acronym "API" stands for Application Programming Interface, and so a
Java API is just something (an "interface", but not in the sense of the Java
keyword) that your Java program can talk to. So for example, if someone uses
the C programming language to writes a library to handle MP3 decoding, but
then wants to make the functionality of that library available to Java
programmers, that person might release a Java API which uses JNI to
translate the method calls to something the C code understands.

   Sometimes people use the term to mean documentation for the API (e.g.
the stuff generated by the "Javadoc" tool). When a someone provides you with
a library, they almost always provide you with the documentation for that
library.

   So if I take your question literally, I'd have to say that PeopleSoft is
not an app, but a company. If they release apps, they may on a case by case
basis decide to release APIs for those apps, or maybe they won't. If they
initially choose not to, it's conceivable that a third party may approach
them and request permission to create an API for their products, but I think
this is rarely down for commercial products (though it's somewhat common in
open source products).

   Assuming the application is written in Java, you could use reflection to
accomplish some of the above.

   - Oliver

1) Yes PeopleSoft provides a Java API.  I'm sure you have to license
PeopleSoft to use it.  If you already have access to a PeopleSoft
installation then you will be able to search for Java in PeopleBooks
and find what you need.

2) "dynamic info" is a very general term you could mean almost
anything.

If you are not already a PeopleSoft customer, search the web in your
favorite search engine for "Java PeopleSoft" there's tons.

This one looks like an interesting place to start.  You have to
register on the site so I didn't go so far as to read the paper...

http://whitepapers.zdnet.com/abstract.aspx?promo=50002&docid=119100

Overview: Java is an extremely popular programming language today,
especially for internet applications. Many PeopleSoft customers have
invested heavily in building Java skills within their IT organization
and would like to leverage this investment within their PeopleSoft
environment. With PeopleSoft 8, developers can definitely leverage
their Java skills with PeopleSoft applications. With PeopleTools 8,
PeopleSoft has added support in several key areas to enable developers
to create Java-based PeopleSoft applications. This white paper provides
an overview and examples of how PeopleSoft customers can develop
applications in Java within the PeopleTools Development Environment of
PeopleSoft 8.