A website called computer-books.us provides information about computer books that are available for free download. I think the website good since it is useful for those who are seeking free online books for computer programming.

I was interested in Java so I clicked on the link to Java Programming. The website then showed me a page that contains links to 11 Java programming books. I then clicked the first link, and saw the book cover of “Enterprise JavaBean Second Edition” with the following statement on the right:

For your free electronic copy of this book please verify the numbers below.
(We need to do this to make sure you’re a person and not a malicious script)

At that point, I expected that I would download the whole electronic copy of the book after I entered the number (which is always the same number–89703) and pressed the “download” button. I went on as instructed and got to the page saying that:

You’ve been verified as a person and not a script!
To download this book, click on the title Enterprise JavaBeans
I hope you find the book useful.

I clicked the link to download a zip file, which I expected it should be the electronic copy of the book. The ending of this story is that, at the end, I just got a 2531-bytes HTML file that points to the online version of the book. At that moment, I had the feeling that I was fooled by the website.

I switched to search engines to check the other books listed in the page, and finally found that most of them had their online version only (in a volume of HTML file). Here are my one-hour work; they point to the direct links to those free Java books.

• Enterprise JavaBeans Second Edition (Publisher: O’Reilly & Associates, Inc. Author: Richard Monson-Haefel; ISBN 1-56592-869-5E; Second edition, published March 2000.)
• Essentials of the Java Programming Language, Part 1 (From Sun Developer Network’s Tutorial & Code Camps; Author: Monica Pawlan, March 1999)
• Essentials of the Java Programming Language, Part 2 (From Sun Developer Network’s Tutorial & Code Camps; Author: Monica Pawlan, July 1999)
• Exploring Java (Publisher: O’Reilly & Associates, Inc. Author: Patrick Niemeyer & Joshua Peck; 1-56592-184-271-9, 500 pages (est.) 2nd Edition July 1997 (est.)
• Introduction to Computer Science using Java (Revised and Expanded, July 2003; Bradley Kjell, Central Connecticut State University)
• Introduction to Programming Using Java (Author: David J. Eck)
• Java AWT Reference (Publisher: O’Reilly & Associates, Inc. Author: John Zukowski; 1-56592-240-9, 1074 pages; 1st Edition April 1997)
• Java Language Reference (Publisher: O’Reilly & Associates, Inc. Author: Mark Grand; 1-56592-326-X, 475 pages; 2nd Edition July 1997)
• Java Servlet Programming (Publisher: O’Reilly & Associates, Inc. Author: Jason Hunter with William Crawford; ISBN 1-56592-391-XE; First edition, published October 1998.)

What do you think about that?

Update: I also found the following two websites that contains a lot of online versions of O’Reilly’s books. I have no idea on why they can do that.

• www.wuppy.net.ru/books/Orelly/
• www.unix.org.ua/orelly/