eRunways

Because of its unfussiness, this my favorite way of organizing and compiling Java programs.

Organizing Java

Here is the file SampleOranization.java which contains a class SampleClass and a driver to test it:

/////////////////////////////////////////////////////////////////////

//

//  Java Organizing And Compiling Guide

//

/////////////////////////////////////////////////////////////////////

class TestClass

{

public static void main (String [] args)

{

SampleClass x;

x = new SampleClass();

x.test();

}

} // end class TestClass

/////////////////////////////////////////////////////////////////////

class SampleClass

{

public SampleClass()

{

}

public void test()

{

System.out.println("Test Works!");

}

} // end class SampleClass

/////////////////////////////////////////////////////////////////////

Notice slashes (/////////…) that separate classes. In more complex cases, I would recommend comments at the top of each class.

Similarly, you can separate methods with a row of the form //—–…, and I would recommend comment methods which are not self-explanatory.

Compiling Java

/user/root/java/ > ls

SampleOranization.java

Note that the directory contains only one file, SampleOranization.java. We now compile it.

/user/root/java/ > javac SampleOranization.java

/user/root/java/ > ls

total 6

SampleOranization.java

SampleClass.class

TestClass.class

Notice that I have created two class files, one for each class defined inside the file I just compiled (SampleOranization.java).

Notice that SampleOranization is not the name of a class inside the file SampleOranization.java, so I don’t a file SampleOranization.class does not get created.

Now let’s try runing the program. We use the java command and give it the name of the class which contains the method named main. In our case, this is the class TestClass.

/user/root/java/ > java TestClass

Test Works

This is the output we expect.