Blanca Polo ICS 111

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JAVA

• Your First Program

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Program Skeleton
public class ProgramName public static void
main(String args) //instructions go
here
Comments
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Comments

• Documentation
• They do not affect how a program works

// this comment runs to the end of the line
/ this comment runs to the terminating
symbol, even across line breaks /
/ this is a javadoc comment /

• Spaces, blank lines, and tabs are called white
  space. Extra white space is ignored.

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Comments and JAVADOC
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Comments and JAVADOC
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First Program
public class FirstProgram public static void
main(String args) System.out.println(
My first JAVA program)
No comments
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What is in a Name?

• Always chose a meaningful name
• Class names are always in capital letter
• Long program names are ok but follow the
  upper/lower case rules.

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The Program
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Java Class Format
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Java Method Format
// comments about the class
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Writing a JAVA program in UNIX
After tying your program in pico ltctrlgtX Y ltente
rgt Once in the command prompt javac
MyProgram.java ltentergt If no errors are found,
run the program by typing java MyProgram ltentergt
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Editing your program in UNIX

• Log into UNIX
• Edit your program using PICO
• Save it
• Compile it
• Run it
• Open PINE to send e-mail
• Attach the file
• Read the instructions carefully and send your
  program!

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Time to Try it out
JAVA in UNIX