Hello World

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Hello World

• The Edit Compile Run cycle, Part 1

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Remember

• Computer programs are models of the real world
• What is a computer program?

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(No Transcript)
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Address the computer through a terminal window
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A Terminal Session

• Log In User name and Password
• A window appears
• Check the prompt
• styx
• styx is the computer (it can be different...
  armstrong, dracula, yeager, many more)
• is a separator
• is your home
• is where you type

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Creating Folders (or Subdirectories, or Work
Areas)

• You type
• yeager mkdir Lab1
• yeager cd Lab1
• yeager /Lab1
• What just happened?
• yeager /Lab1 cd
• yeager

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Work Areas on the main computer disk

mkdir Lab1 cd Lab1
/
Lab1/
/Lab1 Work Area is the location of edited
files
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What is a file?

• Dear John,
• I think we should just be
• friends

Created and Saved in an editor yeager
pico Dearjohn.txt Could be a Java program
yeager /Lab1 pico myProgram.java
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Editors like word processors

• pico
• emacs
• JGrasp
• Eclipse
• any editor can be used
• editors are interchangeable, at any time
• text is IN THE FILE, not in the editor

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Compilation

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what's a JDK?

• Java Development Kit - programs that need to hang
  around let you write and run Java programs on
  your computer

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what's a ClassLib

• what do you THINK it is?