Error when calling pure java code (separate project) from android in eclipse

Question

I have this simple java code:

package com.androiddesktoptest.testtest;

public class AndroidDesktopTestMain
{
    public static void main(String[] args)
    {
        callFromAndroid();
    }

    public static void callFromAndroid()
    {
        System.out.println("DESKTOP CODE CALLED FROM ANDROID");
    }
}

And I want to call it from Android like this:

import com.androiddesktoptest.testtest.AndroidDesktopTestMain;

public void onCreate(Bundle savedInstanceState)
{
    //...
    AndroidDesktopTestMain.callFromAndroid();
}

and I get java.lang.NoClassDefFoundError

I am using Eclipse and my project AndroidDesktopTest has checked to export AndroidDesktopTest/src. Also, eclipse autocomplete my code in Android, so it see correcly my code in desktop project.

What I am doing wrong? I did something like this in my previous-previous-previous project, from this time, maybe ADT has chaged or something...

* UPDATE * entire error 07-20 14:02:56.452: E/AndroidRuntime(30233): java.lang.NoClassDefFoundError: com.androiddesktoptest.testtest.AndroidDesktopTestMain

07-20 14:02:56.452: E/AndroidRuntime(30233): java.lang.NoClassDefFoundError: com.androiddesktoptest.testtest.AndroidDesktopTestMain — SuitUp
– SuitUp, Commented Jul 20, 2012 at 12:31
Anders Metnik - one project export source, and second (Android) has java project in "required project in the build path". Is it enough? — SuitUp
– SuitUp, Commented Jul 20, 2012 at 12:57

Graeme · Accepted Answer · 2012-07-20 13:31:19Z

3

Order & Export isn't the most well built feature of the Android ADT.

If you instead include the linked src folder from the Desktop project to your Android project (Right Click Project > Build Path > Link Source Folder) then the Class will be used as if it belongs to the Android Project.

I think the prefered way of doing this would be to create a jar file or a Library Project but these might be too cumbersome to try until you have stable Deskptop code.

Hope that helps!

answered Jul 20, 2012 at 13:31

Graeme

25.9k27 gold badges127 silver badges189 bronze badges

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

Comments

Anders Metnik · Accepted Answer · 2012-07-20 12:47:58Z

2

Sounds like you don't get the class over to the phone when u run your android.

Make sure that:

right click project - properties - java build path - Order and Export (is it checked here?)

answered Jul 20, 2012 at 12:47

Anders Metnik

6,2677 gold badges43 silver badges80 bronze badges

6 Comments

Anders Metnik Over a year ago

In order and export, move up your external project so it is almost at the top (right under your android project).

Graeme Over a year ago

I think he is referring to the precedence of the library export order.

SuitUp Over a year ago

src is at the top from the beginnning

Anders Metnik Over a year ago

And after that needs to be your java project, else it won't reference it right when you load it onto the device.

Anders Metnik Over a year ago

Else attach a screenshot of it (the export order). And I can explain it out from that.

|

Jan Gerlinger · Accepted Answer · 2012-07-20 13:34:38Z

0

This article about including Java libraries into Android projects suggests replacing the "JRE System Library" with the android.jar for your API level in your linked Java project's build path dialog.

answered Jul 20, 2012 at 13:34

Jan Gerlinger

7,4351 gold badge48 silver badges53 bronze badges

Comments

MicroEyes · Accepted Answer · 2012-07-20 12:41:37Z

-1

try this

new AndroidDesktopTestMain.callFromAndroid();

The only way to call a non-static method from a static method is to have an instance of the class containing the non-static method. By definition, a non-static method is one that is called ON an instance of some class, whereas a static method belongs to the class itself.

answered Jul 20, 2012 at 12:41

MicroEyes

3,7524 gold badges28 silver badges35 bronze badges

3 Comments

SuitUp Over a year ago

What? public static void callFromAndroid()

MicroEyes Over a year ago

I m not getting you.. Have you tried the above code? Is it working?

SuitUp Over a year ago

callFromAndroid is static, so I don't understand your answer... and yes, I tried it (look at another answer, same strange advice).

Collectives™ on Stack Overflow

Error when calling pure java code (separate project) from android in eclipse

4 Answers 4

Comments

6 Comments

Comments

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

6 Comments

Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related