Announcement

Collapse
No announcement yet.

applet-servlet communication, object serialization, problem

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

  • applet-servlet communication, object serialization, problem

    hi,

    I encountered a problem with tomcat 5.5. Grazing the whole web i didn't find any solution (some guys are having the same problem but they also got no useful hint up to now). The problem is as follows:
    I try to build an applet-servlet communication using serialized objects. In my test scenario i write a serialized standard java object (e.g. a String object) onto the ObjectOutputStream of the applet/test-application (it doesn't matters wheter to use the first or the latter one for test cases) and the doPost method of the servlet reads the object from the ObjectInputStream. That works fine. But if i use customized objects (which should also work fine) the same code produces an classnotfound exception. When i try to read and cast the object:
    Code:
    TestMessage e = (TestMessage)objin.readObject();
    
    java.lang.ClassNotFoundException: TestMessage
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1359)
        at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1205)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
    ...
    That seems strange to me, because if i instantiate an object of the same customized class (TestMessage) in the servlet code, the webappclassloader doesn't have any problems loading and handling the class and the code works fine!
    The class is located in the web-inf/classes directory of the application. I've already tried to put the class (with and without the package structure) into the common/classes and server/classes directory, but the exception stays the same (I've also tried to build a jar and put it in the appropriate lib directories).
    I've also tried to catch a Throwable object in order to get information on the cause. But i get a "null" value (the docu says, that this will may be caused by an unknown error).
    I've also inspected the log files intensively. But they gave me no hint. Until now I've spend a lot of time on searching and messing around but i always get this classnotfound exception.
    I hope this is the right place to post this problem and i hope that there is anyone out there who can give me some hint on solving this problem.

    Kindly regards,
    Daniel
Working...
X