Oracle JDBC project with Maven: runs fine in IDE but ClassNotFoundException in command-line

Question

I currently have a class project that consists in making a software in Java using JavaFX and Oracle JDBC. In order to make the project run on the school's computers, we are asked to make it using Java 1.8 and ojdbc6.jar.

I use Maven for this project, and normally I would just have to install ojdbc6 locally, but I need it to work on the teacher's computer, who has the jar file under /opt/oracle/ojdbc6.jar.Thus, I added a copy of this ojdbc6.jar inside my project directory, and I imported the dependency in pom.xml the following way:

<dependency>
    <groupId>com.oracle</groupId>
    <artifactId>ojdbc6</artifactId>
    <version>12.1.0.1.0</version>
    <scope>system</scope>
    <systemPath>${basedir}/ojdbc6.jar</systemPath>
</dependency>

This way, the teacher will be able to compile the project because all it needs is already there.

I understood from other posts that this wasn't a good solution, but as the teacher won't install the jar file locally, I don't really know what else to do.

I am using the following lines to make my program connect to the database:

try {
    Class.forName("oracle.jdbc.OracleDriver");
    connection = DriverManager.getConnection(url, user, passwd);
}
catch /* etc */

The problem is: this works just fine inside IntelliJ, I can make requests to the database and get data, etc. However, when I try to run the project using command-line interface command:

mvn clean compile jfx:run

It works fine until I make an action that uses the database, and I get the following exception:

java.lang.ClassNotFoundException: oracle.jdbc.OracleDriver
        at java.net.URLClassLoader.findClass(URLClassLoader.java:382)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:264)
        at fr.ensimag.equipe3.model.DAO.ConnectionDB.connect(ConnectionDB.java:34)
        at fr.ensimag.equipe3.model.DAO.ConnectionDB.<init>(ConnectionDB.java:29)
        at fr.ensimag.equipe3.model.DAO.ConnectionDB.<clinit>(ConnectionDB.java:12)
        at fr.ensimag.equipe3.model.DAO.UserDAO.get(UserDAO.java:32)
        at fr.ensimag.equipe3.controller.LoginController.connexion(LoginController.java:28)
        at fr.ensimag.equipe3.controller.LoginController.onEnter(LoginController.java:49)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71)
        at sun.reflect.GeneratedMethodAccessor9.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
        at java.lang.reflect.Method.invoke(Method.java:498)
        at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275)
        at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769)
        at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657)
        at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
        at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
        at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
        at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
        at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
        at javafx.event.Event.fireEvent(Event.java:198)
        at javafx.scene.Node.fireEvent(Node.java:8411)
        at com.sun.javafx.scene.control.behavior.TextFieldBehavior.fire(TextFieldBehavior.java:179)
        at com.sun.javafx.scene.control.behavior.TextInputControlBehavior.callAction(TextInputControlBehavior.java:178)
        at com.sun.javafx.scene.control.behavior.BehaviorBase.callActionForEvent(BehaviorBase.java:218)
        at com.sun.javafx.scene.control.behavior.TextInputControlBehavior.callActionForEvent(TextInputControlBehavior.java:127)
        at com.sun.javafx.scene.control.behavior.BehaviorBase.lambda$new$74(BehaviorBase
.java:135)
        at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
        at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
        at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
        at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
        at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
        at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
        at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
        at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
        at javafx.event.Event.fireEvent(Event.java:198)
        at javafx.scene.Scene$KeyHandler.process(Scene.java:3964)
        at javafx.scene.Scene$KeyHandler.access$1800(Scene.java:3910)
        at javafx.scene.Scene.impl_processKeyEvent(Scene.java:2040)
        at javafx.scene.Scene$ScenePeerListener.keyEvent(Scene.java:2501)
        at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:217)
        at com.sun.javafx.tk.quantum.GlassViewEventHandler$KeyEventNotification.run(GlassViewEventHandler.java:149)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleKeyEvent$352(GlassViewEventHandler.java:248)
        at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389)
        at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleKeyEvent(GlassViewEventHandler.java:247)
        at com.sun.glass.ui.View.handleKeyEvent(View.java:546)
        at com.sun.glass.ui.View.notifyKey(View.java:966)
        at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method)
        at com.sun.glass.ui.gtk.GtkApplication.lambda$null$48(GtkApplication.java:139)
        at java.lang.Thread.run(Thread.java:748)

So it looks like Java can't find my ojdbc6.jar file... I tried to display the classpath used by Maven using:

mvn dependency:build-classpath

and it turns out ojdbc6.jar is in the classpath, so I really can't understand why the same program works in IntelliJ but not in command-line interface: I would have thought that both the IDE and mvn jfx:run would run the same commands in order to launch the program.

Thank you for your time if you read this post, I hope I have been clear enough and don't hesitate to tell me if I missed another post that would solve my problem.

Answer 1

Oracle JDBC drivers are on Maven central repos now.

For Java8 / Oracle 12 you should use:

<dependency>
    <groupId>com.oracle.jdbc</groupId>
    <artifactId>ojdbc8</artifactId>
    <version>12.2.0.1</version>
</dependency>

Answer 2

The correct GAV for 12.1.0.1 is given below. Refer to the blog for more details on the versions and the files available.

<dependency>
    <groupId>com.oracle.database.jdbc</groupId>
    <artifactId>ojdbc6</artifactId>
    <version>12.1.0.1</version>
</dependency>