Execuatble jar file

[coltragon]

Hello,

i have created this code:

package javaapplication6;
import java.util.*;
import java.io.*;
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        int radius;
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            System.out.println("Please enter the radius of your circle");
            radius=Integer.parseInt(br.readLine());
            System.out.println("The radius you entered was: "+radius);
            double area=Math.PI*radius*radius;
            System.out.println("Calculating your circle area... please wait...");
            System.out.println("The area of your circle is:"+area);
        }
        catch (IOException ioe) {
            System.out.println("An error has occured:"+ioe);
        }
        

    }
    }

when i run it in Netbeans it works fine, i wanted to sent it to a friend because i was proud of it.

so i built the projects and tried to run the .JAR file but it doesn't do anything?
anyone know why?
heres my jar file:JavaApplication6.zip

thanks in advance, Jesse

[JosAH]

Hello,

i have created this code:

package javaapplication6;
import java.util.*;
import java.io.*;
public class Main {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        int radius;
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            System.out.println("Please enter the radius of your circle");
            radius=Integer.parseInt(br.readLine());
            System.out.println("The radius you entered was: "+radius);
            double area=Math.PI*radius*radius;
            System.out.println("Calculating your circle area... please wait...");
            System.out.println("The area of your circle is:"+area);
        }
        catch (IOException ioe) {
            System.out.println("An error has occured:"+ioe);
        }
        

    }
    }

when i run it in Netbeans it works fine, i wanted to sent it to a friend because i was proud of it.

so i built the projects and tried to run the .JAR file but it doesn't do anything?
anyone know why?
heres my jar file:JavaApplication6.zip

thanks in advance, Jesse

You can run code from a .jar file in two ways:

1) mention your .jar file in your classpath variable and run the class javaapplication6.Main as you always do.

2) double click on your .jar file (this is what most people want to do). If there is a system association between a .jar extension and the java(w) program, the jvm tries to run a class from that .jar file; it has to know which class to run; you mention that class in the 'manifest' file entry in the .jar. Here's an example:

Manifest-Version: 1.0
Created-By: coltragon
Main-Class: javaapplication6.Main
Built-By: coltragon
Name: Circle Application
Specification-Title: Circle Application
Specification-Version: 1.0
Specification-Vendor: coltragon
Implementation-Title: Circle Application
Implementation-Version: 1.0
Implementation-Vendor: coltragon

Many of the lines above aren't necessary. Check the documentation for the jar utility how to add this manifest file to your jar.

kind regards,

Jos

ps. you need to run your program with the 'java' command, not the 'javaw' command because your program needs a console.