Java

How to Think Like a Computer Scientist

Java Version

ii

How to Think Like a Computer Scientist
Java Version

Allen B. Downey

Version 4.1.1

Copyright c 2011 Allen Downey.

Permission is granted to copy, distribute, and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with Invariant Sections being
“Preface”, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the appendix entitled “GNU Free Documentation
License.”
The GNU Free Documentation License is available from www.gnu.org or by writing to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
Boston, MA 02111-1307, USA.
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Preface
“As we enjoy great Advantages from the Inventions of others, we should be glad of an Opportunity to serve others by any Invention of ours, and this we should do freely and generously.”
—Benjamin Franklin, quoted in Benjamin Franklin by Edmund S.
Morgan.

Why I wrote this book
This is the fourth edition of a book I started writing in 1999, when I was teaching at Colby College. I had taught an introductory computer science class using the
Java programming language, but I had not found a textbook I was happy with.
For one thing, they were all too big! There was no way my students would read
800 pages of dense, technical material, even if I wanted them to. And I didn’t want them to. Most of the material was too specific—details about Java and its libraries that would be obsolete by the