BlueJ: a very quick introduction

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BlueJa very quick introduction
Adapted from notes by D. Matuszek, Upenn
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BlueJ

• BlueJ is an IDE
• IDE (InteractiveIntegrated) Development
  Environment
• It includes
• an editor, which you use to write your programs
• a debugger, to help you find your mistakes
• a viewer, to see the parts of your program
• an easy way to run Java programs and program
  components
• an easy way to view documentation
• http//bluej.org/

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(IteractiveIntegrated) Development Environments

• Most IDEs are language specific, tho some basic
  ones can be used with multiple languages.
• There are IDEs for most popular languages (Java,
  C, C, Lisp, Smalltalk, Prolog, )
• There are dozens of IDEs for Java
• Javas capabilities for reflection makes it easy
  to write
• Reflection allows a program to examine or
  "introspect, seeing its own components and
  (even) code.
• IDEs tend to be large, complicated and difficult
  to learn

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BlueJ at UMBC

• Your best bet is to download and install BlueJ on
  your own computer.
• There are specific versions for Windows and MAC
  OS X
• There is a generic Java version that can be run
  on most any machine with Java (e.g., Linux,
  Solaris, )
• BlueJ is installed on O\BlueJ\ on the UMBC OIT
  PC servers
• You may need to show it where the java programs
  are

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Open BlueJ, choose New Project
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Name the project, click Create
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Create and name a newClass or Applet
The name of the class should beginwith a capital
letter
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Double-click the new class to edit it
The stripes show that theclass "Drawing" is
notcompiled (ready to run)
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Edit your class, then Compile it
BlueJ starts you with asimple class or a
simpleapplet. You can modifywhat BlueJ gives
you, orjust replace it with yourown program.
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If it's an applet Right-click the class and
choose Run Applet
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If applet choose how to run it, and what size it
should be
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Here's the running applet!
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If application right-click and choose void
main(args)
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Application Just click Ok
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Application results
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Viewing classes
BlueJs main displayshows all of the classes in
your package and therelationships between them
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Viewing classes and instances
You can interactively create Instances and call
methods Attached to any class
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Final notes

• You don't have to Save your workBlueJ does that
  automatically for you when you compile
• If you quit BlueJ and come back later, use Open
  Project to continue where you left off
• This quick introduction does not replace working
  through the tutorial!

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The End