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javalinuxclassweka

run WEKA on Linux

I have downloaded and unzipped the following WEKA version weka-3-4-19. This is on a linux operating system. I wish to use WEKA through the command line, however on executing 

java weka.classifiers.tress.j48.J48

I get the following error message:

Exception in thread "main" java.lang.NoClassDefFoundError: weka/classifiers/tress/j48/J48
Caused by: java.lang.ClassNotFoundException: weka.classifiers.tress.j48.J48
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: weka.classifiers.tress.j48.J48.  Program will exit.

Can someone help me resolve this? Thank you.

Edit1:

On trying the java -jar weka.jar command

java.awt.HeadlessException:
No X11 DISPLAY variable was set, but this program performed an operation which requires it.
    at java.awt.GraphicsEnvironment.checkHeadless(GraphicsEnvironment.java:159)
    at java.awt.Window.<init>(Window.java:432)
    at java.awt.Frame.<init>(Frame.java:403)
    at javax.swing.JFrame.<init>(JFrame.java:202)
    at weka.gui.GUIChooser.<init>(GUIChooser.java:98)
    at weka.gui.GUIChooser.main(GUIChooser.java:285)

No X11 DISPLAY variable was set, but this program performed an operation which requires it.

Edit 2:

On trying java.weka.classifiers.trees.J48

Exception in thread "main" java.lang.NoClassDefFoundError: weka/classifiers/tress/J48
Caused by: java.lang.ClassNotFoundException: weka.classifiers.tress.J48
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: weka.classifiers.tress.J48.  Program will exit.

Edit 3:

{cslinux2:~/weka-3-4-19} echo $CLASSPATH
/people/cs/j/jld082000/weka-3-4-19/weka.jar:
{cslinux2:~/weka-3-4-19} java weka.classifiers.trees.J48

Weka exception: No training file and no object input file given.

General options:

-t <name of training file>
    Sets training file.
-T <name of test file>
    Sets test file. If missing, a cross-validation will be performed on the training data.
Solution

  • That simply means weka.classifiers.tress.j48.J48 class is not in classpath. You can write java command with -classpath switch or set CLASSPATH (permanent) variable. Another way is to use -jar switch as pointed by @jberg.

    EDIT:

    As I checked (I downloaded Weka 3-4-19 from that site) there is definitely no weka.classifiers.tress.j48.J48 class in weka.jar package. Probably you are looking for:

    java weka.classifiers.trees.J48

    For example:

    $ export CLASSPATH=/home/grzegorz/weka-3-4-19/weka.jar:.
$ echo $CLASSPATH 
/home/grzegorz/weka-3-4-19/weka.jar:.
$ java weka.classifiers.trees.J48

Weka exception: No training file and no object input file given.

General options:

-t <name of training file>
    Sets training file.
...