Loading struts classes into a webapp

Was this ever solved? I am having a similar class loading problem with struts
jars in web-inf/lib in war packaged in an ear with 8.1.
Thanks, Julie
"Vinod Mehra" <[email protected]> wrote:
Hoki,
After looking at the stack trace you sent us, it looks like the same
problem as CR081073. Which has been fixed already for 700sp1.
One off patches are availiable for the 70 version. Please contact
support for a one off patch with CR081073 as reference.
The problem was that the context classloader was not set correctly
while instantiating the servlet.Struts' ActionServlet invokes the
org.apache.commons.logging.LogFactory in the constructor. If it
can be changed to do the same thing in the init method instead it
will work fine.
Let us know if the patch doesn't fix the problem.
Thanks,
--Vinod.
"Nagesh Susarla" <[email protected]> wrote in message
news:[email protected]...
Oops i meant 'not' being honored.
"Manifest-cp specified in WARS was NOT being honored"
thx
-nagesh
Nagesh Susarla wrote:
Hi,
CR074842 fixes manifest related issues.
Please contact wlsupport and request a patch for the above mentioned
CR.
Actually Manifest-classpath specified in WAR's was being honoredand
thats the reason the war cannot find library.jar
hope that helps
nagesh
Ho-Ki Au wrote:
I created a MANIFEST.MF in both the webapp's META-INF directory
and
the WEB-INF
directory and it still doesn't work. Can you tell me how to packagethis:
MyApp.ear:
Library.jar
EJB.jar:
META-INF/MANIFEST.MF has Class-Path: Library.jar
WebApp.war
WEB-INF/lib/struts.jar
WEB-INF/MANIFEST.MF has Class-Path: Library.jarWebApp.war/WEB-INF/lib/struts.jar
META-INF/MANIFEST.MF has Class-Path: Library.jarWebApp.war/WEB-INF-lib/struts.jar
META-INF/application.xml
in exploded directory form. The web app is actually not able toresolve classes
in Library.jar and struts.jar even it uses the EJB and has an EJBreference in
its deployment descriptors.
Can you explain how the webapp classloading works?
"Ajay" <[email protected]> wrote:
Ho-Ki Au <[email protected]> wrote in message
news:[email protected]...
I have lots of trouble understanding how classloading in weblogic
works.
I have
a ear file which contains two ejb-jars, two library jars, and
a
webapp
war
file.
The webapp uses struts and since it is not used by anybody
else, I
put it
in
the webapp's WEB-INF/lib. I did not specify any classpath for
the
webapp
because
the container is supposed to load all jars in the WEB-INF/lib
directory.
I'm deploying it in the exploded directory mode where everythingis
expanded.
So under the application directory, there is a directorymywebapp/WEB-INF/lib
and struts.jar resides there (not expanded).
when i use a browser to launch the app, I saw some stack trace
in
the
console
saying NoClassDefFoundException for class
org/apache/struts/action/Action.
Another question. if I have a jar file which is shared betweenan
ejb and
a webapp,
i put it at the root level of the ear file. in the ejb jar
file, i
can
use the
Class-Path property in MANIFEST.MF to point to it. how can
a
webapp
specify to
use that library jar file?
You can do the same stuff as in EJB with Webapp, but I am notquite
sure
whether it is in Meta-Inf/manaifest or Web-Inf/Manifest in thewebapp
directory
Hope this helps
Ajay
Thanks for help. Please send me email.
-hoki

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Hello,
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library files in web-inf\lib directory. It gave me the error that class not found
for some class in struts library. The console also told me the classpath. But
I can use javap to find the class using the same classpath. Could any one point
me some direction what I am doing wrong here.
Thanks.
Here is the error message:
java.lang.NoClassDefFoundError: org/apache/commons/beanutils/Converter.>
<Nov 13, 2003 11:05:29 AM EST> <Error> <HTTP> <BEA-101216> <Servlet: "action"
fa
iled to preload on startup in Web application: "voppocWebApp".
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oad\voppocWebApp.war;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extrac
t\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\activation30425.jar;C:
\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp
_voppocWebApp\jarfiles\WEB-INF\lib\commons-beanutils30426.jar;C:\bea\weblogic81\
server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\ja
rfiles\WEB-INF\lib\commons-collections30427.jar;C:\bea\weblogic81\server\bin\.\m
yserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF
\lib\commons-digester30428.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdel
ete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\commons-file
upload30429.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\mys
erver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\commons-lang30430.jar;C:\be
a\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_vo
ppocWebApp\jarfiles\WEB-INF\lib\commons-logging30431.jar;C:\bea\weblogic81\serve
r\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfile
s\WEB-INF\lib\commons-validator30432.jar;C:\bea\weblogic81\server\bin\.\myserver
\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\ja
karta-oro30433.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\
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C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebA
pp_voppocWebApp\jarfiles\WEB-INF\lib\mailapi30435.jar;C:\bea\weblogic81\server\b
in\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\W
EB-INF\lib\struts30436.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\
extract\myserver_voppocWebApp_voppocWebApp\jarfiles\_wl_cls_gen.jar.
java.lang.NoClassDefFoundError: org/apache/commons/beanutils/Converter.
at weblogic.servlet.internal.ServletStubImpl.prepareServlet(ServletStubI
mpl.java:800)
at weblogic.servlet.internal.WebAppServletContext.preloadServlet(WebAppS
ervletContext.java:3236)
at weblogic.servlet.internal.WebAppServletContext.preloadServlets(WebApp
ServletContext.java:3181)

Hello Mark,
Your suggested solution (putting an empty commons-logging.properties into
web-inf/classes or in a jar in web-inf/lib)
does not make any change at all. It still complains about not being able to
preload the servlet and still
gives exceptions upong calling upon LogFactory.
What I have been able to do is put the three classes from
com.bea.wlw.netui.util.logging into a separate jar
and add that to web-inf/lib.
However I am sometimes getting funny exceptions upon undeploy
(NoClassDefFoundError for org.apache.commons.collection.FastHashMap$KeySet).
Regards,
Robert Varga
"Mark Griffith" <[email protected]> wrote in message
news:[email protected]...
From a FAQ on netui:
1. Why do I get a ServletException while trying to deploy a struts web
application on a Workshop/Integration/Portal domain?
In the "<WL-HOME>/server/lib/knex.jar" file there is a properties file
called "commons-logging.properties" which configures the
com.bea.wlw.netui.util.logging.StrutsLogFactory class for Struts loggingas
below:
org.apache.commons.logging.LogFactory=com.bea.wlw.netui.util.logging.StrutsL
ogFactory
This class file is not available for a Struts web application that was not
built using Workshop, the reason being the containing NetUI jar files are
not present in the web application's WEB-INF/lib folder. This leads to a
ServletException while deploying the web application. The solution is toadd
a blank file (or a JAR containing the file) namedcommons-logging.properties
to the server CLASSPATH, or to the WEB-INF/lib folder of the concerned web
application. This issue will be fixed in Service Pack 2.
cheers
mbg
"Robert Varga" <[email protected]> wrote in message
news:[email protected]...
Hi Rob,
I also have a similar error with deploying a Struts web application into
a
8.1 Basic Workshop Domain created
by 8.1 Platform.
I get a ClassNotFoundException for 'com.wlw...StrutsLogFactory', whenStruts
tries to load any Jakarta class
from commons-beanutils or Struts which has logging.
This happens because commons-logging picks up some property whichinstructs
it to load that class, which is
naturally not included in most web applications, since it is
workshop-specific. This property definition, I think,
is in <bea>\weblogic81\server\knex.jar, called
commons-logging.properties,
containing the following line:
org.apache.commons.logging.LogFactory=com.bea.wlw.netui.util.logging.StrutsL
ogFactory
How can I override this in my webapp in a property file, so that when a
Struts or Beanutils class calls
LogFactory.getLog(org.apache.....<classname>.class), it would not try touse
the property file and the
class defined in knex.jar.
Thanks in advance,
Robert Varga
"Rob Woollen" <[email protected]> wrote in message
news:[email protected]...
Actually it complained about a NoClassDefFoundError. Generally this
is
caused by something in a parent classloader that is found but then
depends on something only loadable in a child classloader.
eg.
You have something in your $CLASSPATH that references something in the
WEB-INF/lib. This will NoClassDefFoundError.
So, as I recommended, remove everything you've added to the$CLASSPATH,
add the jars to WEB-INF/lib. If you're still having problems, show me
your $CLASSPATH, the contents of WEB-INF/lib, and the error message
/stack trace.
-- Rob
yuruo chen wrote:
Hello, Rob,
I did put the common-beanutils and other jar files in the
web-inf/lib
directory.
And from the weblogic console, I do see the jar file get included in
the
classpath.
(those generated file name have some number attached at the end.)
As
I
mentioned
before, I can use javap find the class using this weblogic generatedclasspath.
But weblogic complained that the class is not found.
Rob Woollen <[email protected]> wrote:
Remove anything you've added to the server's classpath.
Add the required jar files to WEB-INF/lib
-- Rob
yuruo chen wrote:
Hello,
I am tring to deploy my struts web application in weblogic 8.1. I
have
all the
library files in web-inf\lib directory. It gave me the error that
class
not found
for some class in struts library. The console also told me the
classpath.
But
I can use javap to find the class using the same classpath. Could
any
>>>>>
one point
me some direction what I am doing wrong here.
Thanks.
Here is the error message:
java.lang.NoClassDefFoundError:
org/apache/commons/beanutils/Converter.>
<Nov 13, 2003 11:05:29 AM EST> <Error> <HTTP> <BEA-101216>
<Servlet:
>>>>>
"action"
fa
iled to preload on startup in Web application: "voppocWebApp".
javax.servlet.ServletException:
[HTTP:101250][ServletContext(id=9921725,name=vop
pocWebApp,context-path=/voppocWebApp)]: Servlet classorg.apache.struts.action.A
ctionServlet for servlet action could not be loaded because a classon which it
depends was not found in the classpath
C:\bea\weblogic81\server\bin\myserver\upl
>
oad\voppocWebApp.war;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extrac
>
t\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\activation30425.jar;C:
>
\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp
>
_voppocWebApp\jarfiles\WEB-INF\lib\commons-beanutils30426.jar;C:\bea\weblogic81\
>
server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\ja
>
rfiles\WEB-INF\lib\commons-collections30427.jar;C:\bea\weblogic81\server\bin\.\m
>
yserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF
>
\lib\commons-digester30428.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdel
>
ete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\commons-file
>
upload30429.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\mys
>
erver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\commons-lang30430.jar;C:\be
>
a\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_vo
>
ppocWebApp\jarfiles\WEB-INF\lib\commons-logging30431.jar;C:\bea\weblogic81\serve
>
r\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfile
>
s\WEB-INF\lib\commons-validator30432.jar;C:\bea\weblogic81\server\bin\.\myserver
>
\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\ja
>
karta-oro30433.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\
>
myserver_voppocWebApp_voppocWebApp\jarfiles\WEB-INF\lib\jdbc2_0-stdext30434.jar;
>
C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\extract\myserver_voppocWebA
>
pp_voppocWebApp\jarfiles\WEB-INF\lib\mailapi30435.jar;C:\bea\weblogic81\server\b
>
in\.\myserver\.wlnotdelete\extract\myserver_voppocWebApp_voppocWebApp\jarfiles\W
>
EB-INF\lib\struts30436.jar;C:\bea\weblogic81\server\bin\.\myserver\.wlnotdelete\
extract\myserver_voppocWebApp_voppocWebApp\jarfiles\_wl_cls_gen.jar.
java.lang.NoClassDefFoundError:
org/apache/commons/beanutils/Converter.
atweblogic.servlet.internal.ServletStubImpl.prepareServlet(ServletStubI
mpl.java:800)
atweblogic.servlet.internal.WebAppServletContext.preloadServlet(WebAppS
ervletContext.java:3236)
atweblogic.servlet.internal.WebAppServletContext.preloadServlets(WebApp
ServletContext.java:3181)

Is there a restriction on loading "javax" classes from WEB-INF/lib?

I'm having trouble with a webapp in WL 10MP1 that is having trouble loading classes from the "jsr311-api-1.0.jar" in my WEB-INF/lib. Even though I have no trouble with it in Eclipse (no compile errors), classes from that jar fail with "NoClassDefFound" exceptions. I have a feeling it might be the fact that the packages in that jar start with "javax". Assuming that's the case, is there anything I can do to fix this?
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Unable to load Driver Class

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java.lang.ClassNotFoundException: java.io.FileNotFoundException: C:\oracle\jdbc\
driver\OracleDriver.class (The system cannot find the path specified)
The following code snippet fails because it is unable to find the suitable driver.
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Hi,
maybe I'm too late but try the following :
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Or Your classesxxx.zip file is corrupt.
We had this error after downloading the classes12.zip for Oracle versions
higher 8.1.6.
The original size of this file is 1.888kB.
Remember Windows FTP is downloading in ascii mode per default.
Or Your classpath isn't correct
( the Exception souns like this )
Regards

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This message appears every time I plug my phone into the computer and itunes pops up

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Loading an image into an Applet from a JAR file

Hello everyone, hopefully a simple question for someone to help me with!
Im trying to load some images into an applet, currently it uses the JApplet.getImage(url) method just before registering with a media tracker, which works but for the sake of efficiency I would prefer the images all to be contained in the jar file as oppossed to being loaded individually from the server.
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I don't touch applets, so I can't help you there, but here's some Friday Fun: tracking image loading.
import java.awt.*;
import java.awt.image.*;
import java.beans.*;
import java.io.*;
import java.net.*;
import javax.imageio.*;
import javax.imageio.event.*;
import javax.imageio.stream.*;
import javax.swing.*;
public class ImageLoader extends SwingWorker<BufferedImage, Void> {
    private URL url;
    private JLabel target;
    private IIOReadProgressAdapter listener = new IIOReadProgressAdapter() {
        @Override public void imageProgress(ImageReader source, float percentageDone) {
            setProgress((int)percentageDone);
        @Override public void imageComplete(ImageReader source) {
            setProgress(100);
    public ImageLoader(URL url, JLabel target) {
        this.url = url;
        this.target = target;
    @Override protected BufferedImage doInBackground() throws IOException {
        ImageInputStream input = ImageIO.createImageInputStream(url.openStream());
        try {
            ImageReader reader = ImageIO.getImageReaders(input).next();
            reader.addIIOReadProgressListener(listener);
            reader.setInput(input);
            return reader.read(0);
        } finally {
            input.close();
    @Override protected void done() {
        try {
            target.setIcon(new ImageIcon(get()));
        } catch(Exception e) {
            JOptionPane.showMessageDialog(null, e, "Error", JOptionPane.ERROR_MESSAGE);
    //demo
    public static void main(String[] args) throws IOException {
        final URL url = new URL("http://blogs.sun.com/jag/resource/JagHeadshot.jpg");
        EventQueue.invokeLater(new Runnable(){
            public void run() {
                launch(url);
    static void launch(URL url) {
        JLabel imageLabel = new JLabel();
        final JProgressBar progress = new JProgressBar();
        progress.setBorderPainted(true);
        progress.setStringPainted(true);
        JScrollPane scroller = new JScrollPane(imageLabel);
        scroller.setPreferredSize(new Dimension(800,600));
        JPanel content = new JPanel(new BorderLayout());
        content.add(scroller, BorderLayout.CENTER);
        content.add(progress, BorderLayout.SOUTH);
        JFrame f = new JFrame("ImageLoader");
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setContentPane(content);
        f.pack();
        f.setLocationRelativeTo(null);
        f.setVisible(true);
        ImageLoader loader = new ImageLoader(url, imageLabel);
        loader.addPropertyChangeListener( new PropertyChangeListener() {
             public void propertyChange(PropertyChangeEvent evt) {
                 if ("progress".equals(evt.getPropertyName())) {
                     progress.setValue((Integer)evt.getNewValue());
                     System.out.println(evt.getNewValue());
                 } else if ("state".equals(evt.getPropertyName())) {
                     if (SwingWorker.StateValue.DONE == evt.getNewValue()) {
                         progress.setIndeterminate(true);
        loader.execute();
abstract class IIOReadProgressAdapter implements IIOReadProgressListener {
    @Override public void imageComplete(ImageReader source) {}
    @Override public void imageProgress(ImageReader source, float percentageDone) {}
    @Override public void imageStarted(ImageReader source, int imageIndex) {}
    @Override public void readAborted(ImageReader source) {}
    @Override public void sequenceComplete(ImageReader source) {}
    @Override public void sequenceStarted(ImageReader source, int minIndex) {}
    @Override public void thumbnailComplete(ImageReader source) {}
    @Override public void thumbnailProgress(ImageReader source, float percentageDone) {}
    @Override public void thumbnailStarted(ImageReader source, int imageIndex, int thumbnailIndex) {}
}

How to load a .class file dynamically?

Hello World ;)
Does anyone know, how I can create an object of a class, that was compiled during the runtime?
The facts:
- The user puts a grammar in. Saved to file. ANTLR generates Scanner and Parser (Java Code .java)
- I compile these file, so XYScanner.class and XYParser.class are available.
- Now I want to create an object of XYScanner (the classnames are not fixed, but I know the filename). I tried to call the constructor of XYScanner (using reflection) but nothing works and now I am really despaired!
Isn't there any way to instantiate the class in a way like
Class c = Class.forName("/home/mark/XYScanner");
c scan = new c("input.txt");
The normal call would be:
XYLexer lex = new XYLexer(new ANTLRFileStream("input.txt"));The problem using reflection is now that the parameter is a ANTLRFileStream, not only an Integer, as in this example shown:
Class cls = Class.forName("method2");
Class partypes[] = new Class[2];
partypes[0] = Integer.TYPE;
partypes[1] = Integer.TYPE;
Method meth = cls.getMethod("add", partypes);
method2 methobj = new method2();
Object arglist[] = new Object[2];
arglist[0] = new Integer(37);
arglist[1] = new Integer(47);
Object retobj = meth.invoke(methobj, arglist);
Integer retval = (Integer)retobj;
System.out.println(retval.intValue());Has anyone an idea? Thanks for each comment in advance!!!

Dump all of your class files into a directory.
Use the File class to list all files and iterateover
the files.NastyNot really, when you are dynamically creating code, I would expect the output to be centralized, not spread out all over the place.
>
Use a URLClassloader to load the URL that isobtained
for each file with file.toURI().toURL()(file.toURL()
is depricated in 1.6)Wrong, the URL you give it must be that of the
directory, not the class file.No, I did this quite recently, you can give it a specific class file to load.
>
Load all of the classes in this directory, thatway
any anonymous classes are loaded as well.Anonymous classes automatically loaded when the real
one isIt can't load it if it doesn't know where the code is. Since you haven't used a URL classloader to load once class file at a time, you would never encounter this. But if you loaded a class file that had an anonymous classfile it needed, would it know where to look for it?
>
From this point you should be able to just get a
class with Class.forName(name)No. Class.forName uses the classloader of the class
it's called in, which will be the system classloader.
It won't find classes loaded by a URLClassLoader.got me there.

How to load a class , which isn't in the classpath environment variable.

Hi, you folks.
I have one problem. I want to load a class, which isn't in the classpath
environment variable and I don't want to put into classpath. which method
JVM can use to load it?
Waitting for your sage advice.
Regareds
Hunter.Xiao

You will have to write your own ClassLoader, or use something like URLClassLoader (I've never used this myself, but I've seen it mentioned elsewhere in this forum). Look here.

LoadClass (error loading a class which extends other class at run-time)

Hey!
I'm using the Reflection API
I load a class called 'SubClass' which exists in a directory called 'subdir' at run-time from my program
CustomClassLoader loader = new CustomClassLoader();
Class classRef = loader.loadClass("SubClass");
class CustomClassLoader extends ClassLoader. I have defined 'findClass(String className)' method in CustomClassLoader.
This is what 'findClass(String className)' returns:
defineClass (className,byteArray,0,byteArray.length);
'byteArray' is of type byte[] and has the contents of subdir/SubClass.
the problem:
The program runs fine if SubClass does not extend any class.
If however, SubClass extends another class, the program throws a NoClassDefFoundError. How is it conceptually different?
Help appreciated in Advance..
Thanks!

Because i'm a newbie to the Reflection thing, i'm notI don't see reflection anywhere. All I see is class loading.
sure what role does the superclass play when i'm
trying to load the derived class and how to get away
with the errorWell... hint: all the superclass's stuff is not copied into the subclass.
I am quite sure it fails to load the superclass because of classpath issues.

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