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I want you to read over this information. if it seems a
little confusing just relax we are just getting you used to the language and
even if it doesn't REALLY mean much to you right now it will when we start
putting it to use more. What we are setting up for here is what I call (in the
words of Laura Croft) an "ahaa" moment so really I want you to scan
this over a time two don't worry I wont be quizzing you yet but do read it. You
are learning another language and that takes time and effort before you become
literate in it so put the effort in and stick with me here.
To print to
standard output you type
System.out.println(string); an example of this would be
System.out.println("Your Looking Good Today!");
Variables: To
lay the base down in programming languages Variables are your starting blocks
acting as a place in memory to store a value . There are basically
3 kind of variables local, field and class. You will want to consider the
following characteristics of the variable, Data
Type, Scope, Lifetime , Initial Value, Names, and Declaration.
You can name your Variable almost anything, except
for after java keywords. if we name our variable "lesson" as in lesson
= 4; the script will translate it into 4. if you type System.out.println(lesson);
it will show as 4 in the Java Console. Refering
back to when you built your application again you have already used this
/**
* The LamersSuckApp class implements an application that
* displays "Lamers Suck!" to the standard output.
*/
public class LamersSuck {
public static void main(String[] args) {
// Display "Lamers Suck!"
System.out.println("Lamers Suck!");
}
}
If your going to use a variable you
will need to declare its type. The different types of data the variable
holds some primitive data types are int, short, long, byte, float, double,
char, and boolean.
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Type
|
|
What the hell does that mean?
|
|
int
|
|
An integer between -2,147,483,648
and 2,147,483,647.
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|
short
|
|
An integer between -32,768 to
32,767.
|
|
long
|
|
An integer between
-9,223,372,036,854,775,808L to 9,223,372,036,854,775, 807L.
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|
byte
|
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Uses 8 bits to represent a number
from -128 to 127
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|
float
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Represents integers with
fractional parts such as 12.3456. Valid values span 6-7 decimal digits
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|
double
|
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Valid values span 15 decimal
digits.
|
| char |
|
represents single characters
between single quotes using Unicode encoding. |
| boolean |
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An integer that can be either true or false. |
Okay that's enough for now get ready to make your second applet in the next
lesson so we can keep this as hands on as possible.
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