Results 1 to 5 of 5
  1. #1
    ITSlave is offline Member
    Join Date
    Sep 2011
    Posts
    6
    Rep Power
    0

    Default Error: Could not find or load main class

    I've searched through the forum and reviewed the other threads on this topic and can't figure out what I'm doing wrong. I'm a java noob taking a grad class that someone didn't tell me would require java. My first assignment was to modify 2 classes, a client and server class for outputing the current date. Instead, I'm supposed to make it output a random joke. The code is working in the Netbeans IDE, but I cannot get it to run from the command line. I am able to compile the code just fine, but when I go to run it here is what I get:

    c:\Temp>java JokerServer
    Exception in thread "main" java.lang.NoClassDefFoundError: JokerServer (wrong na
    me: Assignment1/JokerServer)
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java :791)
    at java.security.SecureClassLoader.defineClass(Secure ClassLoader.java:14
    2)
    at java.net.URLClassLoader.defineClass(URLClassLoader .java:449)
    at java.net.URLClassLoader.access$100(URLClassLoader. java:71)
    at java.net.URLClassLoader$1.run(URLClassLoader.java: 361)
    at java.net.URLClassLoader$1.run(URLClassLoader.java: 355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.j ava:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:4 23)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:3 56)
    at sun.launcher.LauncherHelper.checkAndLoadMain(Launc herHelper.java:472)

    I also tried:

    c:\Temp>java c:\temp\JokerServer
    Error: Could not find or load main class c:\temp\JokerServer

    And:

    c:\Temp>java -cp . JokerServer
    Exception in thread "main" java.lang.NoClassDefFoundError: JokerServer (wrong na
    me: Assignment1/JokerServer)
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(ClassLoader.java :791)
    at java.security.SecureClassLoader.defineClass(Secure ClassLoader.java:14
    2)
    at java.net.URLClassLoader.defineClass(URLClassLoader .java:449)
    at java.net.URLClassLoader.access$100(URLClassLoader. java:71)
    at java.net.URLClassLoader$1.run(URLClassLoader.java: 361)
    at java.net.URLClassLoader$1.run(URLClassLoader.java: 355)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.j ava:354)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:4 23)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:308)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:3 56)
    at sun.launcher.LauncherHelper.checkAndLoadMain(Launc herHelper.java:472)


    What am I doing wrong?

  2. #2
    JosAH's Avatar
    JosAH is offline Moderator
    Join Date
    Sep 2008
    Location
    Voorschoten, the Netherlands
    Posts
    14,043
    Blog Entries
    7
    Rep Power
    23

    Default Re: Error: Could not find or load main class

    Your class is in a package named 'Assignment1' so its full name is 'Assignment1.JokerServer' and you should run it as such (your JVM was trying to tell you so).

    kind regards,

    Jos
    The only person who got everything done by Friday was Robinson Crusoe.

  3. #3
    DeNiS_M is offline Member
    Join Date
    Sep 2011
    Location
    Athens Greece
    Posts
    29
    Rep Power
    0

    Default Re: Error: Could not find or load main class

    try java <package-name>.JokeServer
    Ig that doesn't work just post the code so that we can see what might be wrong.

  4. #4
    ITSlave is offline Member
    Join Date
    Sep 2011
    Posts
    6
    Rep Power
    0

    Default Re: Error: Could not find or load main class

    It gave me an error when I tried to use java Assignment1.JokerServer. However, I went into the project, and deleted the package. Once the class files were in the default package, I was able to run them. Thanks for the help.

  5. #5
    Tolls is offline Moderator
    Join Date
    Apr 2009
    Posts
    12,474
    Rep Power
    21

    Default Re: Error: Could not find or load main class

    If it gave you an error then you ought to post it here.

    I suspect you put the class in a package Assignment1, but didn't actually have the class file in an Assignment1 directory.
    Removing the package statement simply stuck it in the default package, which is not a good habit to get into.

Similar Threads

  1. Replies: 10
    Last Post: 02-02-2012, 09:26 PM
  2. Replies: 29
    Last Post: 02-02-2012, 09:23 PM
  3. Could not find or load main class BubbleSort.class
    By blaqkout in forum New To Java
    Replies: 5
    Last Post: 09-12-2011, 07:54 PM
  4. runtime error 'could not find main class' ?
    By ruud00000 in forum Java Applets
    Replies: 5
    Last Post: 12-31-2010, 06:58 PM
  5. [SOLVED] Could not find the main class: error...
    By bobleny in forum New To Java
    Replies: 21
    Last Post: 03-02-2010, 11:53 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •