Programming Language and Java
1.1 Your First Java Program: Hello World
In this section, our plan is to lead you into the world of Java programming by taking you through the three basic steps required to get a simple program running. The Java system is a collection of applications not unlike any of the other applications that you are accustomed to using (such as your word processor, e-mail program, or internet browser). As with any application, you need to be sure that Java is properly installed on your computer. You also need an editor and a terminal application. Here are system specific instructions for three popular home operating systems. [ Mac OS X · Windows · Linux ]
Programming in Java.
We break the process of programming in Java into three steps: 1. Create the program by typing it into a text editor and saving it to a file named, say, MyProgram.java. 2. Compile it by typing "javac MyProgram.java" in the terminal window. 3. Run (or execute) it by typing "java MyProgram" in the terminal window.
The first step creates the program; the second translates it into a language more suitable for machine execution (and puts the result in a file namedMyProgram.class); the third actually runs the program. • Creating a Java program. A program is nothing more than a sequence of characters, like a sentence, a paragraph, or a poem. To create one, we need only define that sequence characters using a text editor in the same way as we do for e-mail. HelloWorld.java is an example program. Type these character into your text editor and save it into a file named HelloWorld.java.
|public class HelloWorld { |
|public static void main(String[] args) { |
|System.out.println("Hello, World"); |
|} |
|}
In this section, our plan is to lead you into the world of Java programming by taking you through the three basic steps required to get a simple program running. The Java system is a collection of applications not unlike any of the other applications that you are accustomed to using (such as your word processor, e-mail program, or internet browser). As with any application, you need to be sure that Java is properly installed on your computer. You also need an editor and a terminal application. Here are system specific instructions for three popular home operating systems. [ Mac OS X · Windows · Linux ]
Programming in Java.
We break the process of programming in Java into three steps: 1. Create the program by typing it into a text editor and saving it to a file named, say, MyProgram.java. 2. Compile it by typing "javac MyProgram.java" in the terminal window. 3. Run (or execute) it by typing "java MyProgram" in the terminal window.
The first step creates the program; the second translates it into a language more suitable for machine execution (and puts the result in a file namedMyProgram.class); the third actually runs the program. • Creating a Java program. A program is nothing more than a sequence of characters, like a sentence, a paragraph, or a poem. To create one, we need only define that sequence characters using a text editor in the same way as we do for e-mail. HelloWorld.java is an example program. Type these character into your text editor and save it into a file named HelloWorld.java.
|public class HelloWorld { |
|public static void main(String[] args) { |
|System.out.println("Hello, World"); |
|} |
|}