Threads are "flows of control" or "flows of
execution" where your program seems to "do
more than one thing at a time." (Unless you
run the program on a computer with more than
one CPU, it really only does one thing at a
time. Very quickly, but one at a time.)
There are several good Java books for learning
about threads and multi-threaded programming.
I like one by Doug Lea, called
"Concurrent Programming in Java, 2nd Edition"
It has a lot of very good information.
Beans are either
Java Beans, a type of Java class which is
"self contained" to make it easy to use in several
types of tools, or
Enterprise Java Beans (EJBs), one of the topics
which is appropriate for this forum. They are
also special classes which are "self contained"
but for use in several different server products,
commercial and freeware.
A good book for learning about them might be the
one that Java Ranch is giving away this week,
"Professional Java Server Programming
J2EE,
1.3 Edition." The publisher notes at Amazon.com
say
"This book is for professional Java developers
who want to employ Java as the platform for their
distributed, enterprise applications. It provides
a comprehensive guide to the J2EE APIs implemented
by J2EE-licensed application servers.
No knowledge of J2EE technologies is assumed...."
How you use these things depends almost entirely
on what you're trying to do. If you're trying to
learn about them, get some open source products
like
Tomcat (jakarta.apache.org) and/or
JBoss (www.jboss.org) and begin with the examples,
then experiment.
Joe
