Using methods from a .jar file in Java

Question

Question about Java. I'm using Eclipse, and I've created a simple project called Main. In this project there's a class called MainClass.

public class MainClass
{
}

I have another project called Math. It has only one class called Functions, and it's got one method called add:

public class Functions
{
    public int add(int a, int b)
    {
        return a+b;
    }
}

I've exported this project called Math into a .jar file. I want to use the add method from the .jar file in the project Main, for example:

public class MainClass
{
    int x = add(1, 2);
}

What do I have to do? Thanks for your time.

Edit: Ok, I've added the jar in the lib folder, but now, how do I use add(int a, int b)? It says it is "undefined".

2nd Edit: I created an instance of the class Functions, so now I can use the methods. Thanks for your replies!

welcome to Stack Overflow. If you find a anser helpful, you can accept it :) — mtk
– mtk, Commented Sep 14, 2012 at 14:03
Post the code of what you have tried. If post an SSCCE you will get the solution faster. — basiljames
– basiljames, Commented Sep 15, 2012 at 6:27

Amit Deshpande · Accepted Answer · 2012-09-14 13:23:41Z

3

create folderlib add your jar to it. goto Project->Properties->Java Build Path-> Libraries->Add Jar and you are done.

answered Sep 14, 2012 at 13:23

Amit Deshpande

19.2k4 gold badges48 silver badges72 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Rookie Programmer Aravind Over a year ago

Thanks for adding this answer @AmitD.. it was great help!

Kamal · Accepted Answer · 2012-09-14 13:23:42Z

0

You should include the .jar in your .classpath file. Once this step is done, you can use the method.

answered Sep 14, 2012 at 13:23

Kamal

4,1284 gold badges23 silver badges24 bronze badges

Comments

Samuel · Accepted Answer · 2012-09-14 13:24:39Z

0

You need to include the .jar file in Main's classpath.

Right click on the Main project in Eclipse, click properties, click "Java Build Path", click "Libraries", click add jar or add external jar and find the .jar file. That's it!

answered Sep 14, 2012 at 13:24

Samuel

17.3k6 gold badges65 silver badges77 bronze badges

Collectives™ on Stack Overflow

Using methods from a .jar file in Java

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

1 Comment

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related