ClassNotFoundException when trying to deploy with JNLP?

Question

I have an application written in Java that uses Maven to build. I'd like to deploy it using JNLP. This is the folder structure I have:

MyProject
├── pom.xml
├── src
│   ├── main
│   │   ├── java
│   │   │   ├── folder
│   │   │   │   ├── to
│   │   │   │   │   ├── my
│   │   │   │   │   │   ├── project
│   │   │   │   │   │   │   ├── ClassWithMain.java
│   │   ├── jnlp
│   │   │   ├── myjnlp.jnlp
│   │   │   ├── myjar.jar
│   │   │   ├── mymanifest.txt
│   │   │   ├── keystore
│   │   │   ├── pageToLaunchJnlp.html
├── target
│   ├── classes
│   │   ├── folder
│   │   │   ├── to
│   │   │   │   ├── my
│   │   │   │   │   ├── project
│   │   │   │   │   │   ├── ClassWithMain.class

I created the jar using mymanifest.txt and the ClassWithMain.class from within the target folder, and I signed it using the keystore and a timestamp url.

There are other files besides ClassWithMain, but that's the one with the main method.

But when I try to run the jnlp file, I get the error:

java.lang.ClassNotFoundException: folder.to.my.project.ClassWithMain
    at java.net.URLClassLoader.findClass(Unknown Source)
    at com.sun.jnlp.JNLPClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at com.sun.jnlp.JNLPClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at com.sun.javaws.Launcher.doLaunchApp(Unknown Source)
    at com.sun.javaws.Launcher.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

Here's my jnlp file below. I took out the codebase attribute since I saw the tutorial of deploying without a codebase at this link. My HTML file uses the launchWebStartApplication and createWebStartLaunchButtonEx functions, but I still get the ClassNotFoundException.

I've tried changing it to main.java.folder.to.my.project.ClassWithMain, but that doesn't work either.

<?xml version="1.0" encoding="utf-8"?>
<jnlp spec="1.0"
      href="myjnlp.jnlp">
    <information>
        <title>My Project</title>
        <description>My Project Webstart</description>
        <offline-allowed/>
    </information>
    <security>
        <sandbox/>
    </security>

    <resources>
        <j2se href="http://java.sun.com/products/autodl/j2se" version="1.6+" initial-heap-size="512m"
              max-heap-size="512m"/>
        <property name="sun.java2d.noddraw" value="true"/>
        <jar href="myjar.jar" main="true"/>
    </resources>
    <application-desc main-class="folder.to.my.project.ClassWithMain"/>
</jnlp>

Here's where my ClassWithMain is located according to the jar tvfcommand: Users/myusername/MyProject/target/classes/folder/to/my/project/ClassWithMain.class

Is this an issue with my folder structure, and if so, what is the correct structure/location for the jnlp file, jar file, keystore, etc. so the main class file is detected properly?

Thanks, any help is appreciated.

Answer 1

Your folder structure should be like this -

MyProject
├── pom.xml
├── src
│   ├── main
│   │   ├── java
│   │   │   ├── folder
│   │   │   │   ├── to
│   │   │   │   │   ├── my
│   │   │   │   │   │   ├── project
│   │   │   │   │   │   │   ├── ClassWithMain.java
            resources
            ├── folder
            │   ├── to
            │   │   ├── my
            │   │   │   ├── project
                            ├── myjnlp.jnlp
                            ├── myjar.jar
                            ├── mymanifest.txt
                            ├── keystore
                            ├── pageToLaunchJnlp.html

you will get

├── target
│   ├── classes
│   │   ├── folder
│   │   │   ├── to
│   │   │   │   ├── my
│   │   │   │   │   ├── project
│   │   │   │   │   │   ├── ClassWithMain.class
                        ├── myjnlp.jnlp
                        ├── mymanifest.txt
                        ├── pageToLaunchJnlp.html

At the run time myjnlp.jnlp will get ClassWithMain.class at same location. And yes I doubt about your jar location it should not be where you were showing, second think keystore, why you need to keep in build ? if you need it should be move to meta-inf of your build.