Java Program Structure|Core Java Tutorial for Beginners|G C Reddy|

Sections of Java Programming, Documentation Section -Optional, Package Declaration Statement, Import Statement/s, Class Declaration / Statement, Interface Section (Outside of main method and inside of the class), Main Program, Create Object //Based on the Program requirement, Call Methods //Based on the Program requirement,
Normal Statements, Variable Declarations, Print Statements, operation etc, and Code Blocks //Based on the Program requirement.

Example:
//It is a Sample Program to explain the Program structure and Syntax of Java...

package xyza;

import java.io.File;

public class Sample {
//Interface section
static int x=100;

public int add(int a, int b) {
int result =a+b;
return result;
}

public static void main(String[] args) {
//Main Program
System.out.println(x+y);//300
Sample obj = new Sample(); // Create Object
int res= obj.add(100, 300);//Call a Method
System.out.println(res);

res= obj.multiply(10, 37);
System.out.println(res);//370

int a=10;
int b=20;

double d=10.98;
char c='E';

System.out.println("Hell Java");
System.out.println(a+b);

if (a b)
{
System.out.println("A is Big Number");
}
else
{
System.out.println("B is Big Number");
}
System.out.println("");
for (int i=1; i =5; i++) {
if (i!=4) {
System.out.println(i);
}
}

}
//Interface section

static int y=200;

public int multiply(int x, int y) {
int result =x*y;
return result;
}

}

1. Documentation Section - Optional

2. Package Declaration - Mandatory

3. Import Statement/s - Depends on your program requirement

4. Class Declaration - Mandatory

5. Interface Section (Outside of the main method (before/after), and Inside of the Class)
Declare variables and methods
Note: we can write comments in interface section, but writing comments is optional

6. main method (Program execution starts from the main method)
Main program - Code with in main method

Within main Program
7. Write Comments, but writing comments is optional
8. Declarations (Variables, Constants / Final Variables)
9. Normal Statements (Print Statements, Operations etc,)
10. Create Object
11. Call method/s
12. Write Code Blocks (Conditions/Loops/Constructor etc,)