Downloadable Java implementations

This document describes three Java implementations that can be downloaded for free. In each case, the implementation consists of an IDE (integrated development environment, with a graphical user interface that includes a text editor), and Sun Microsystems' Java SDK (software development kit), which has to be downloaded separately.

Two of these implementations, TextPad and Eclipse, are referred to in the 46A lab exercises and are available in the student labs. TextPad is easier to use than Eclipse, but not as fully featured. The third, BlueJ, is intermediate between the other two in difficulty and in relevant features. BlueJ and Eclipse are free, while TextPad is shareware.

TextPad (and the Java SDK) are bundled with (new) copies of the CS 46A text. If you don't have a new copy of the text, instructions for downloading them are given in the lab manual.

If you download the SDK before TextPad is first run, then there should be no problem in using Java from within TextPad, as described in Lab Exercise 2. Otherwise, see the instructions for enabling the Java tools in TextPad in the "How do I add the JDK commands?" question in the FAQ (frequently asked questions) at http://www.textpad.com/support/faq/java.html

It's convenient to have TextPad configured so that running a Java application opens a window that doesn't immediately disappear. Then you can use the File -> SaveAs menu choice to save your output to a text file. You can close the output window using the File -> Close menu choice. If your output window does close immediately and automatically, you can fix this problem by checking the checkbox in the Preferences menu for "capture output".

The BlueJ download site is http://www.bluej.org/download/download.html. The Eclipse download site is http://eclipse.org. Eclipse and how to download it are discussed in Lab Exercise 6. Remember that if you download BlueJ or Eclipse, you will still need to download and install the Java SDK separately (unless you have already done that).

Downloading the Java SDK
To download the Java SDK, start at http://java.sun.com/j2se/1.4.2/download.html. Download the SDK of J2SE v 1.4.2 (or later edition, if you find one). For Windows, try Windows Installation before Windows Offline Installation.