# Help me for main method

• 05-26-2009, 12:11 PM
eliCanzee
Help me for main method
Hi I have done the project but I don't know how to add "main" method or better to say I don't know how to create main class for this :

import javax.swing.*;
import java.awt.*;
import java.awt.geom.*;

/**
Sims the shot of a cannonball. Allows user to input trajectory and velocity.
@author Josh

*/
public class Cannonball
{

/** Names angle of ball. */
private double angle;

/** Gives horizontal distance of ball. */
private double x;

/** Vertical distance of ball */
private double y;
/** Names velocity, or speed cannonball will travel. */
private double velocity;

/** The time that the ball is checked. */
public static final double dT = 0.01;

/** Gravity's effect on the ball. */
public static final double GRAVITY = 9.81;

/** Makes a new ball. */
public Cannonball(double speed, double ang)
{
velocity = speed;
angle = ang * Math.PI / 180;
x = 0;
y = 0;
}
/** Gets speed that ball is moving at. */
public double getSpeed()
{
return velocity;
}
/** Allows user to set velocity. */
public void setSpeed(double vel)
{
velocity = vel;
}
/** Gets angle of ball. */
public double getAngle()
{
return angle;
}
/** Lets user set angle. */
public void setA(double ang)
{
angle = ang;
}
/** Gets length of ball travel. */
public double getX()
{
return x;
}
/** Allows length to be set. */
public void setX(double xVal)
{
x = xVal;
}
/** Gets height of ball travel. */
public double getY()
{
return y;
}
/** Lets setting of y value. */
public void setY(double yVal)
{
y = yVal;

}
}
• 05-26-2009, 12:43 PM
RamyaSivakanth
Hi
I have highted the main method in green.Please go thru the sunsite for better undestanding the language.As u are in urgency I told u.

Code:

```import javax.swing.*; import java.awt.*; import java.awt.geom.*; /** Sims the shot of a cannonball. Allows user to input trajectory and velocity. @author Josh */ public class Cannonball { /** Names angle of ball. */ private double angle; /** Gives horizontal distance of ball. */ private double x; /** Vertical distance of ball */ private double y; /** Names velocity, or speed cannonball will travel. */ private double velocity; /** The time that the ball is checked. */ public static final double dT = 0.01; /** Gravity's effect on the ball. */ public static final double GRAVITY = 9.81; /** Makes a new ball. */ public Cannonball(double speed, double ang) { velocity = speed; angle = ang * Math.PI / 180; x = 0; y = 0; } /** Gets speed that ball is moving at. */ public double getSpeed() { return velocity; } /** Allows user to set velocity. */ public void setSpeed(double vel) { velocity = vel; } /** Gets angle of ball. */ public double getAngle() { return angle; } /** Lets user set angle. */ public void setA(double ang) { angle = ang; } /** Gets length of ball travel. */ public double getX() { return x; } /** Allows length to be set. */ public void setX(double xVal) { x = xVal; } /** Gets height of ball travel. */ public double getY() { return y; } /** Lets setting of y value. */ public void setY(double yVal) { y = yVal; } [COLOR="SeaGreen"][B]public static void main(String args[]) {         Cannonball obj = new Cannonball();             //Call whatever method u want using                 obj.method name }//main[/B]}  }//class [/COLOR]```