Introduction

• The Basics: How much do you weigh on other planets?
  •      Version 1: A simple program, comments, semicolon, output
  •      Version 2: Variables, assignment, arithmetic, string concatenation
  •      Version 3: Precedence, parenthesis, type cast, named constants
  •      Scanner Class: Simple form of I/O
                 (Could also use Console IO without the use of the Scanner Class)
    See handout [doc] of the above examples
      
• First BlueJ Program. (See screen shots of running it in ACCC labs.) Also see CFX Hello World program
• Output using Strings. Also see CFX Strings examples
• Planet weights programs, revisted
  •      Input using JOptionPane, including number formatting. Also see CFX examples of JOptionPane and number formatting
  •      Input using BufferedReader for console input. Also see CFX example
• The if statement, the switch statement
• Loops: while, do-while, and for
• break and continue
• Objects and Classes
  • Objects and Classes (has link to BlueJ shapes example)
  • Development of Date examples class handout.doc; also see the directory of code for Date class versions, and some further notes on static methods and variables.
  • Example of variable and parameter scope in Confuse.java (and the Word version)
  • Example (MS Word) of Employee class, with a trace
    (See directory of the source code),
  • See also a few diagrams illustrating object references and how they change
• Arrays: grouping data
• Recursion: a method directly or indirectly calling itself
• ArrayList and LinkedList: dynamically created a list
  
  Advanced Topics
  
• Inheritance: Creating a hierarchy of classes that selectively share date and operations
• Interfaces: A "contract" with the outside world for a class to have certain methods defined.
• Mouse Input requires us to implement a Java Interface.

Downloads for getting started

• Java Compiler
  Download JDK 6 (also called Java SE Development Kit (JDK)). Follow the online instructions for this 73.08 MB download.
  
  
• BlueJ
  To download BlueJ, see http://www.bluej.org/download/download.html where you can download the latest version of BlueJ. The Barnes and Kolling BlueJ book also includes the examples (601K .zip file) from that book. See a browsable local copy of these examples. If you are working on these examples in lab, you should save your files either to your desktop or to the H: drive, since you are not allowed to save files on the C: drive. You may consider bringing in a flash drive to save your work.
  
        Once you've downloaded and installed both the Java JDK as well as BlueJ, then launch the BlueJ application. When it first starts it may ask you for help in locating Java. If you have your own Windows machine this will likely be somewhere like:
         C:\Program Files\Java\jdk1.6.0_12\bin\java.exe
  

  See this set of screen shots showing how to write a BlueJ program that gives output to a terminal window.

• Eclipse
  This is a nice Integrated Development Environment (IDE). For Eclipse, download the latest version from
            http://download.eclipse.org/eclipse/downloads

Online Java Books and Tutorials

• See the online free book Introduction to Programming Using Java, by David Eck, which includes a downloadable pdf version. See a local copy (Aug. 2009)
• Online free book Thinking in Java, 3rd Edition, by Bruce Eckel. You may also browse the source code for the book. See the original download site.
• Javabat.com has live Java coding exercises that you can try for free, developed by Nick Parlante at Stanford.
  
  
• Bradley Kjell gives an online beginner's Introduction to Java, along with review questions.
• Fred Swartz has an online tutorial for Java Basics
• Explanation and many examples are given at Dick Baldwin's Programming Tutorials

Running BlueJ in SEL 2249F (and many other ACCC labs)

See this pictoral tutorial of how to find BlueJ on the ACCC lab machines.

If BlueJ has recently been installed and is not yet configured, you may need the steps below. You may need to do something similar when setting up BlueJ at home. Normally you will not need to do these steps. You will possibly need to do something like the steps below only the first time you run BlueJ on your system.

When BlueJ starts you have to manually choose a Java version. One way to do this is shown in the pictoral tutorial linked to above. Alternatively you can do this two ways:

1. Select the "Search for Java Version" button within the BlueJ popup window. After about 5 seconds, it should find the path to C:\j2sdk1.4.2\bin\java.exe, which you should then select.

2. Choose the option to "browse" for it. When you browse for it the C: drive does not show up. However, if you manually enter in C:\ you will see the C: drive. From there navigate to C:\j2sdk1.4.2\bin and point to java.exe. BlueJ will then work fine.

Running BlueJ in SEL 2254 (CS Linux Lab)

In order to configure your CS account to easily run BlueJ from the Linux lab, you should first copy the CS 107 account settings file into your account. This settings file is called .tcshrc, and it sets up your environment to do various useful things, including correctly setting an alias so that you can easily start up BlueJ. The instructions to copy over this settings file into your account are given below.

You will first need to get a terminal window to use in typing in the commands described below.

Getting a terminal window if you are on the Linux machines:

To get the terminal window, after you login click on the Red Hat on the lower left-hand corner of the screen.  From there select the System Tools menu.  Then select Terminal (it has a terminal icon that you should click on).  See the screenshot.

Updating your settings file

First make sure you are in the root of your home directory (type cd and then press the ENTER key if you're not sure), and type the following two lines after your prompt (press ENTER after each line):

cp ~i107/.tcshrc .
source .tcshrc

You will only need to do the above steps once. After doing it the first time, it will already be set up for you the next time you login.

Running BlueJ

Open up a terminal window and type bluej followed by ENTER.  If you are in the Linux lab, BlueJ will start up and you can use it the same as you do on the Windows XP machines.

Customizing your GNOME desktop

The Linux machines are running the GNOME desktop.  On the GNOME desktop, you can customize your panel.  Open up a new window (right-click on the desktop, then select New Window...), and type the following in the Location text field:

~i102/launchers

Press ENTER and you'll be taken to a directory where you will see three application launchers (shortcuts, in Windows terminology).  Drag and drop these application launchers into your panel.  See the screenshot.

Other Java links

• Java 1.6 (aka Java 6) API Documentation, Operator Precedence
• Sun's tutorial trail on learning Java, though not particularly accessible for beginners
• Fred Swartz has many detailed examples (including more advanced topics) in his Java Notes
• See further non-beginner examples at the CS 340 site