One of Java's greatest features is its cross-platform capability.
The same exact Java binary file can run on many different operating systems:
... and many different microprocessors:
Java accomplishes this by defining a "Virtual Machine" that operates on its own set of instructions (called bytecodes). This "Virtual Machine" is then written for each target Operating System / Processor so that it can read the bytecodes and execute the program.
This is particularly important for applications that need to be shared by people over the internet who may be using different operating systems on different processors.
Here's one of the simplest Java programs that simply prints out the message "Hello World!!":
- Code: Select all
import java.io.*;
public class hello {
public static void main ( String[] args ) {
System.out.println ( "Hello World!!" );
}
}
The code is very similar to another popular programming language called "C":
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#include <stdio.h>
int main ( int argc, char **argv ) {
printf ( "Hello World!!\n" );
}
Now programming isn't for everyone. It can be tedious work. But for those interested in making a computer do exactly what you want there's no better alternative.
So far, I've used Java on our US Hawks forum to make animations (like the circling Little Hawk):
... and for support programs (like this US Hawks Voting Machine):
I suspect we'll find many other uses, so anyone interested in learning Java is encouraged to post here and maybe we can get a Java Programming class started.