//Comments begin with a “//”. Note that all keywords are written in red

//in the comments.

//*******************************************************************

// Lincoln.java Author: Lewis and Loftus

//

// Demonstrates the basic structure of a Java class

//*******************************************************************

//the Java interpreter or compiler ignores all of the characters after “//”

//the syntax for a class definition is “modifer class class-identifer”. In

//this case, the modifer is public and the identifier is “Lincoln”.

//Identifiers like “Lincoln” are chosen by the person who writes the

//program, but the name chosen must follow the rules of Java.

//public means that the whole world has access to this class.

public class Lincoln

{ //Again, notice that the class is contained in

//a opening brace “{“ and

// a closing brace “}”

//---------------------------------------------------

// A class to print a presidential quote

//---------------------------------------------------

//A method has the format modifier returnType identifierName.

//The modifier is public, meaning it is accessible to the

//world. It does not return anything, so it has the void as

//the return type. void means nothing is returned.

public void quote()

{ //The method’s definition is contained between

//the opening brace “{“ and

//the closing brace “}”

System.out.println("A quote by Abraham Lincoln:");

System.out.println("Whatever you are, be a good one.");

}

}

//The System.out.println is a call to a Java supplied class (an API)

//”System”, which contains a class of type PrintStream called “out”, which

//has a method called “println”. This sends whatever is in the quotes

//to the standard output, which is the console window.

//So “System.out.println” is a simple way for the program to communicate

//with the outside world. It sends output to the console window. It

//only sends “Strings” to the outside world.

//*******************************************************************

// testLincoln.java Author: Lewis and Loftus

//

// Demonstrates the basic structure of a Java application

//*******************************************************************

public class TestLincoln

{ // the class definition is contained

// between “{“

// and “}”

//---------------------------------------------------

// Calls class to print a presidential quote

//---------------------------------------------------

public static void main(String[] args)

{ //the definition of the method “main is

//also contained between “{“

// and “}”

Lincoln example = new Lincoln();

example.quote();

}

}

//Insider the class we have one method, whose name is “main”.

//All java programs start at the method called “main”, so there can

//be at most one method called “main” in a Java program. This program

//creates an object of type “Lincoln”, defined above. The object is

//given a name of “example”, a user defined name. The keyword new

//means create a new object of this class. “main” returns nothing

//so its return type is void, and it is public so that the world has

//access to it. The term static attached to the method “main”

//signifies that “main” is class method and is not attached to any

//object.

//Finally, the method “quote” of the object “example” is called

//from the class Lincoln. The method “quote” then prints out the

//quote from Abraham Lincoln. The method “quote” is not a static

//method, and hence can only be called though an object of the class.