Slide 4.2: My first Java program (cont.) Slide 4.4: Naming conventions Home

Basic Syntax

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The following list gives the basic syntax of Java:

• Case sensitivity: It means identifiers Hello and hello have different meaning.


• Class names: For all class names, the first letter should be in upper case. If several words are used to form a name of the class, each inner word’s first letter should be in upper case (e.g., MyFirstJavaClass).


• Method names: All method names should start with a lower case letter. If several words are used to form the name of the method, then each inner word’s first letter should be in upper case (e.g., myMethodName).


• Program file names: Name of the program file should exactly match the class name. When saving the file, you should save it using the class name and append .java to the end of the name.
  
  
  ^†If the file name and the class name do not match, your program will not compile. In case you do not have a public class present in the file, then file name can be different from class name. It is also not mandatory to have a public class in the file.
  
  For example, assuming MyFirstJavaProgram is the class name, the file should be saved as MyFirstJavaProgram.java.


• public static void main(String args[]): Java program processing starts from the main() method which is a mandatory part of every Java program. Any code inside the main() method will be executed.


• Miscellaneous syntax:
  
  
  • Each code statement must end with a semicolon.
  • Every line of code that runs in Java must be inside a class.
  • Having a semicolon at the end of class is optional.
  • A line containing only white space, possibly with a comment, is known as a blank line, and Java totally ignores it.

Review: Checking Syntax

Which statement is NOT true?   Each code statement must end with a semicolon.   Every line of code that runs in Java must be inside a class.   Java is case sensitive.   The main( ) method is optional for a Java program.

Result:

Slide 4.2: My first Java program (cont.) Slide 4.4: Naming conventions Home

“If you’re reading this...           Congratulations, you're alive.           If that’s not something to smile about,           then I don’t know what is.”           ― Chad Sugg, Monsters Under Your Head