I wrote a simple multiplayer JAVA app that can connect to MySQL using JDBC driver.
I ended up packing it up in .jar file. When I was testing on my local machine MacOS, it was fine. (I don't exactly remember all the steps to set up JDBC driver, because it was year ago when I wrote this app). The app at this time connects to an external database on another server (I didn't change that because it had no problems). It would be another error if it was a problem with the remote database.
Now, when I need to put it on production on Windows Server 2003, I keep getting the standard error :
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
And I don't get it, because I think I've done the steps right:
0. Installed Java
1. downloaded this: http://dev.mysql.com/downloads/connector/j/
2. added it to the same folder where the app.jar is
3. wrote in cmd: set CLASSPATH =.;C:\Documents and Settings\Administrator\Desktop\tvplan_exchange\mysql-connector-java-5.1.28-bin.jar
4. tested the variable: echo %CLASSPATH% and it showed the same path
5. runned the app: java -jar app.jar
6. got the error:
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at svagers.Db.connect(Db.java:21)
at svagers.Server.main(Server.java:58)
MYSQL ERRORcom.mysql.jdbc.Driver
Well, for those who think that using app like this is a security error - no worries, that is not a problem, I just need it to be running not to consider risks :)
This is the environment:
OS: Windows Server 2003 (Standard Edition, Service Pack 2)
Java: 1.7.0_45 (SE Runtime Environment
I was going to say "run the app with java -cp %CLASSPATH% -jar app.jar" but then remembered you can't have both: you use either -jar or -cp. See this answer.
Related
I have a Java Project (an application to play connect 4) and I want to turn it into an executable file. I created this project in VsCode, and I am using the Java Language Server (see details below). I extracted the .jar file, and used Launch4J to turn it into an executable, and when I run it, I get an error message (see below).
I researched the problem, and it seems that I need to compile my code targeting Java SE 8 rather than 17 (I have 17 currently installed). Could anyone explain to me how I should do this, or is there anything else I'm doing wrong?
The project has multiple files. I'm not sure if this is relevant, but the project has no external dependencies, although it does use javax.swing, javax.sound, and java.awt (as well as java.io.File, java.io.IOException, and java.util.Random, but I'm pretty sure those are irrelevant).
I have eclipse installed if it's necessary, but I only installed it today, and have no experience using it at all. The JDK I am using is (I believe) version 1.8.0_321. (At least this is what I get when I type in java -version.)
The Java compiler version is javac 17.0.2
When I try to run the executable generated by Launch4J, I this is the error I get:
Exception in thread "main" java.lang.UnsupportedClassVersionError: Main has been compiled by a more recent version of the Java Runtime (class file version 61.65535), this version of the Java Runtime only recognizes class file versions up to 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
And the popup error:
Java Virtual Machine Launcher
Error: A JNI error has occurred, please check your installation and try again.
Here are the Settings I used in Launch4J:
Output File: C:\Users\username\OneDrive\Coding\Java Connect 4 v.2\Connect 4.exe
Jar: C:\Users\username\OneDrive\Coding\Java\Java Connect 4 v.2\Java Connect 4 v.2.jar
Don't wrap the jar, launch only: NOT ticked
Wrapper Manifest: none
Change dir: .
Command Line args: none
Process priority: Normal
Both Options NOT ticked
Min JRE version: 1.2.0, Prefer public JRE, but use JDK runtime if newer
Max JRE version: none, First 64-bit, then 32-bit. (This was the default.)
All other settings are default.
Download the latest Java JDK version as .exe file (“x64 Installer”) and install by clicking on the .jar file.
Now the server should start again
#Holger has answered this question. The answer to the problem was to ship a custom JRE image with the application with the help of JLink. That way it can be used regardless of the local version of JRE.
I've written a code that is supposed to be exporting a set of windows registry keys. I've successfully written the code and was able to also send the results of executing the code as a jar file to my email. However, while testing the jar file ( I've included the piece of code in the build.xml from the java website that will allow me to run the jar file out of the dist folder) I was able to get the desired results on my machine because I wrote the code on a windows 8.1 machine. While testing it on another machine ( with Windows 8 and Windows 7 professional ) I was not able to execute the code and the error I was getting was as follows :
"Java Virtual Machine Launcher, A Java Exception has occurred."
I used to get that error message when I did not include the code in the build.xml page to allow the jar file to run out of the dist folder, but now I'm getting it when I'm executing the jar file on different machines other than my own
Running it from the command prompt this is what i got:
Exception in thread "main" java.lang.UnsupportedClassVersionError: smc_1/SMC_1
W1 : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
#Sara, that error is a JVM mismatch error. I think you're trying to run a jar compiled for Java 8 on a system with Java 7 (or older) installed. Your options are (a) update the JVM to Java 8 or (b) recompile your application with the target set to 1.7 or whatever JVM you need to target, provided that your app doesn't include any Java 8-specific code. Oracle has some information on updating Java to the latest version here: http://www.java.com/en/download/help/java_update.xml
First off. I am a newbie and green with respect to Java programming.
I created a Java Eclipse "SWT" "Application Window" on a Eclipse Kepler 4.3.1 (32-bit) running WindowBuilder and SWT (swt.jar). The design view is a composite.
The java application runs fine from Eclipse. I simply press the play button and presto.
Problem:
Issuing
java -cp . PkgNetAccelerator32.netAcceleratorApp
yields the following error message:
Exception in thread "main" java.lang.NoClassDefFoundError: org/eclipse/swt/widgets/Composite
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at sun.launcher.LauncherHelper.getMainMethod(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.eclipse.swt.widgets.Composite
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 6 more
I was doing some research and several posts on other issues suggested that the cure is to create a manifest. I saw an article that said something like:
Select the src folder, right click and select export, then Java, then JAR file, specify Manifest.jar and a path on the folder, make sure the "Generate the manifest file" is selected, and press finish.
I created the manifest file and tried launching it with the following command line:
java -jar ../Manifest.jar -cp . PkgNetAccelerator32.netAcceleratorApp
That yielded the same error message above.
I saw another article that said that one should add in the swt.jar file, but that is taken care of by the manifest. No? Specifying "swt.jar" instead of the manifest that I created resulted in an error message:
no main manifest attribute, in ../swt.jar
That error message makes sense.
I am at a loss. How do I run the java application?
I am testing on my Windows 7 Professional 64-bit desktop, but I need to run on CENTOS too. That should be no problem, as I assume whatever the fix on Windows is, will work on CENTOS.
UPDATE:
I placed the two lib files in a /lib folder to match the answer given. I then issued the following command line and got the following error message.
C:\SoftDev\Projects\NetAccelerator\JavaWorkspace\NetAccelerator32>java -cp "bin/*;lib/*" PkgNetAccelerator32.netAcceleratorApp
Exception in thread "main" java.lang.UnsatisfiedLinkError: Cannot load 32-bit SWT libraries on 64-bit JVM
at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source)
at org.eclipse.swt.internal.Library.loadLibrary(Unknown Source)
at org.eclipse.swt.internal.C.<clinit>(Unknown Source)
at org.eclipse.swt.widgets.Display.<clinit>(Unknown Source)
at PkgNetAccelerator32.netAcceleratorApp.open(netAcceleratorApp.java:43)
at PkgNetAccelerator32.netAcceleratorApp.main(netAcceleratorApp.java:33)
I found the following article, which produces a command line that works, just that is not reasonable for sending. I much rather use the answer.
Lets assume you have a eclipse project structure similar to this:
Workspace
-> Project
-> src (source code directory)
-> bin (compiled byte code directory as JAR)
-> lib (jar directory)
-> .classpath (eclipse file)
-> .project (eclipse file)
I am assuming that you are exporting the JAR as an executable JAR.
So in order to run a class in that exported JAR with another JAR from the lib directory (swt.jar) while your working directory is the Project directory you will need to execute:
java -cp "bin/*:lib/*" PkgNetAccelerator32.netAcceleratorApp
Using wildcards requires Java 6 or later
Please note: CENTOS requires : as a path separator. Windows uses a semi-colon.
This will add your classes and the swt classes onto the classpath and run your main class PkgNetAccelerator32.netAcceleratorApp
SWT 32bit vs 64bit
You will either need to use a 32bit JVM locally or continue to use a 64bit JVM and use the 64bit version of swt; see swt on windows 64 bit. I would suggest you match your version of your local JVM (32bit or 64bit) with the version that you will be running on the CENTOS machine. You will however need a different swt jar for CENTOS.
Hi I've just installed Pentaho Data Integration v. 5.01 and I'm trying to connect to a database. However, I'm unable to test the connection as I get the error (pasted below).
I have JDK 1.7 installed on the system as well, however I can't seem to locate ojdbc14.jar anywhere.
I downloaded that and pasted it in pentaho's \lib folder but I still get the same error.
Any solutions to this problem?
Error connecting to database [test] : org.pentaho.di.core.exception.KettleDatabaseException:
Error occured while trying to connect to the database
Driver class 'oracle.jdbc.driver.OracleDriver' could not be found, make sure the 'Oracle' driver (jar file) is installed.
oracle.jdbc.driver.OracleDriver
org.pentaho.di.core.exception.KettleDatabaseException:
Error occured while trying to connect to the database
Driver class 'oracle.jdbc.driver.OracleDriver' could not be found, make sure the 'Oracle' driver (jar file) is installed.
oracle.jdbc.driver.OracleDriver
at org.pentaho.di.core.database.Database.normalConnect(Database.java:415)
at org.pentaho.di.core.database.Database.connect(Database.java:353)
at org.pentaho.di.core.database.Database.connect(Database.java:306)
at org.pentaho.di.core.database.Database.connect(Database.java:294)
at org.pentaho.di.core.database.DatabaseFactory.getConnectionTestReport(DatabaseFactory.java:84)
at org.pentaho.di.core.database.DatabaseMeta.testConnection(DatabaseMeta.java:2459)
at org.pentaho.ui.database.event.DataHandler.testDatabaseConnection(DataHandler.java:541)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.pentaho.ui.xul.impl.AbstractXulDomContainer.invoke(AbstractXulDomContainer.java:329)
at org.pentaho.ui.xul.impl.AbstractXulComponent.invoke(AbstractXulComponent.java:139)
at org.pentaho.ui.xul.impl.AbstractXulComponent.invoke(AbstractXulComponent.java:123)
at org.pentaho.ui.xul.swt.tags.SwtButton.access$500(SwtButton.java:26)
at org.pentaho.ui.xul.swt.tags.SwtButton$4.widgetSelected(SwtButton.java:121)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at org.eclipse.jface.window.Window.runEventLoop(Window.java:820)
at org.eclipse.jface.window.Window.open(Window.java:796)
at org.pentaho.ui.xul.swt.tags.SwtDialog.show(SwtDialog.java:375)
at org.pentaho.ui.xul.swt.tags.SwtDialog.show(SwtDialog.java:301)
at org.pentaho.di.ui.core.database.dialog.XulDatabaseDialog.open(XulDatabaseDialog.java:115)
at org.pentaho.di.ui.core.database.dialog.DatabaseDialog.open(DatabaseDialog.java:62)
at org.pentaho.di.ui.spoon.delegates.SpoonDBDelegate.newConnection(SpoonDBDelegate.java:493)
at org.pentaho.di.ui.spoon.delegates.SpoonDBDelegate.newConnection(SpoonDBDelegate.java:478)
at org.pentaho.di.ui.spoon.Spoon.doubleClickedInTree(Spoon.java:2885)
at org.pentaho.di.ui.spoon.Spoon.access$2300(Spoon.java:332)
at org.pentaho.di.ui.spoon.Spoon$27.widgetDefaultSelected(Spoon.java:5657)
at org.eclipse.swt.widgets.TypedListener.handleEvent(Unknown Source)
at org.eclipse.swt.widgets.EventTable.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Widget.sendEvent(Unknown Source)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Unknown Source)
at org.eclipse.swt.widgets.Display.readAndDispatch(Unknown Source)
at org.pentaho.di.ui.spoon.Spoon.readAndDispatch(Spoon.java:1227)
at org.pentaho.di.ui.spoon.Spoon.waitForDispose(Spoon.java:7368)
at org.pentaho.di.ui.spoon.Spoon.start(Spoon.java:8673)
at org.pentaho.di.ui.spoon.Spoon.main(Spoon.java:625)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.pentaho.commons.launcher.Launcher.main(Launcher.java:134)
Caused by: org.pentaho.di.core.exception.KettleDatabaseException:
Driver class 'oracle.jdbc.driver.OracleDriver' could not be found, make sure the 'Oracle' driver (jar file) is installed.
oracle.jdbc.driver.OracleDriver
at org.pentaho.di.core.database.Database.connectUsingClass(Database.java:474)
at org.pentaho.di.core.database.Database.normalConnect(Database.java:399)
... 45 more
Caused by: java.lang.ClassNotFoundException: oracle.jdbc.driver.OracleDriver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at org.pentaho.di.core.database.Database.connectUsingClass(Database.java:467)
... 46 more
Try placing the odbc jar file (eg: ojdbc5-11.1.0.7.0.jar) inside the "data-integration/lib" directory of your installation. Don't forget to restart Pentaho to make it work.
Here's my setup. I had this problem and managed to fix it as follows.
I have SQLDeveloper running on my machine and it works OK, even under VPN. However, I was running Spoon and noticed that it wouldn't work if I use VPN.
I have tried to put Oracle JDBC drivers shipped with SQLDeveloper into Pentaho. That didn't work.
However, I noticed that one big difference between SQLDeveloper and Spoon is that they use different
Java runtimes and JDBC Oracle drivers! In particular, my version of SQLDeveloper is running on 32-bit JRE version 1.6.0_11, whereas my system-wide JDK is 64-bit version 1.7.0_03.
I have found the JDBC drivers that SQLDeveloper uses and used them as a replacement for the driver that is shipped with Spoon -- no change.
Then I retargeted Spoon to use the Java runtime used by SQLDeveloper.
I set two environment variables: PENTAHO_JAVA and PENTAHO_JAVA_HOME -- and it works OK now!
For reference, here are my envvars:
PENTAHO_JAVA=C:\opt\sqldeveloper\jdk\jre\bin\java.exe
PENTAHO_JAVA_HOME=c:\opt\sqldeveloper\jdk\jre\
If that is relevant, I am on Windows 7 x64.
1. First go to Oracle Site:
http://www.oracle.com/technetwork/database/features/jdbc/index-091264.html
2. Download 1 file: ojdbc6.jar
(2,739,670 bytes) - (SHA1 Checksum: a483a046eee2f404d864a6ff5b09dc0e1be3fe6c)
Classes for use with JDK 1.6. It contains the JDBC driver classes except classes for NLS support in Oracle Object and Collection types.
3. Copy it into Pentaho folder: C:\Program Files\Pentaho\data-integration\lib
4. Close Spoon if it is open and re-open again. (transferred from the comment of #mishkin - thanks him)
That works on my Windows 7 X64 Pro with latest Pentaho 5.3 Stable.
In Pentaho version 6.0 put the driver (ojdbc6.jar) in: "PentahoInstallation"\design-tools\data-integration\lib and restart the Data Integration ide.
See, guys we doesn't need all these stuff. We need to paste oracle jdbc driver (ojdbc6.jar) in the following location.
C:\Program Files\pentaho\design-tools\report-designer\lib\jdbc
C:\Program Files\pentaho\design-tools\data-integration\lib
C:\Program Files\pentaho\design-tools\aggregation-designer\lib
C:\Program Files\pentaho\design-tools\schema-workbench\lib
try to put ojdbc driver in libext/JDBC in your PDI path (location)
Try putting the jar on tomcat library folder, then restart Pentaho.
Should be here .../biserver-ce-6.0.0.0-353/biserver-ce/tomcat/lib
There are already some drivers here.
I could solve this issue by selecting Oralce Native connection > Hostname as Ip address of DB server > instead of SN00XXXX I had used DB00XXX name for the Database name.
I hope this works for such issues with oracle connectivity.
In my case, the error was in Report designer
The fix: only copy ojdbc14.jar to
\prd-ce-5.0.1-stable\report-designer\lib
and restart the tool.
My run script start.bat
java -server -Xmx1024m -Xbootclasspath/p:"/Java/Server Applet/bin" applet.Server
When I execute it from SSH terminal ./start.bat
I get this:
Exception in thread "main" java.lang.NoClassDefFoundError: applet/Server
Caused by: java.lang.ClassNotFoundException: applet.Server
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
. Program will exit.in class: applet.Server
Yet when I login using vncviewer, and run the script it runs fine. What could be wrong?
There error seems to indicate a class path error, Java can't find this file:
/Java/Server Applet/bin/applet/Server.class
And like Chochos writes, you can't use any graphical (awt, swing, applet) stuff in this program if you are connect by SSH. Although that is not what this error seems to complain about.
You can use some graphic functions in SSH mode if you run Java in headless mode by adding the following command line parameter:
-Djava.awt.headless=true
But this does not give full graphical access:
Sun Developer network: Using Headless Mode in the Java SE Platform:
Many methods in the java.awt.Toolkit and java.awt.GraphicsEnvironment classes, with the exception of fonts, imaging, and printing, require the availability of a display device, keyboard, and mouse. But some classes, such as Canvas or Panel, can be executed in headless mode. Headless mode support has been available since the J2SE 1.4 platform
You need to use ssh -X to let the remote session use your X server. With VNC you use the local graphic environment (of the remote server) so no problem, but with ssh you are running a remote program in a session with no GUI.