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/**
Author:
Date:
Language Version:
Course:
Section:
File Name:
Classes:
Description:
JChildress
2-12-07
Java2 1.5.0_06
CS1043
1
Hello.java
Hello
This program demonstrates how to
output a message.
*/
public class Hello
{
public static void main( String[] args )
{
System.out.printf( "Hello students.\n" );
}
}
// end of class Hello
General Statements about the Java programming language:

A Java program consists of blocks of program statements
organized into classes and methods. Classes and methods
consist of a
o header line
o body of code. The body of code is enclosed in a
matching set of (curly) braces { … }


Braces must be in matching pairs.
Braces can be nested.


Program statements end with a semicolon ;
Header lines do not end with a semicolon

Java is a free-form language. This means that the amount of
empty space and new lines between operators, keywords,
identifiers, classes, and methods is adjustable by the
programmer. Example:
public class Hello{public static void main(String[]
args){System.out.printf("Hello students.\n")}}

Java allows for annotations (aka comments) from the
programmer using the // character sequence and the /*, */
character sequences. The compiler ignores all statements
from the // to the end of the current line. The /*, */
combination is used to create a block of annotations.
Everything between these character sequences is ignored by
the compiler.

Java is case sensitive: Hello is different from hello.

The Java compiler is javac. It is used to find the syntax
errors and convert the source into byte code.

The Java interpreter is known as java. It is used to
execute the statements using a computer. The Java
interpreter is the Java Virtual Machine.

Java programs are in files that have a program name prefix
followed by the suffix .java
o
Our example is Hello.java