I am hazarding a guess here that the InstrumentationFactory is to do
with enhancement of JPA entities. I thought, for some reason, that the
JPA entities were no longer required to be enhanced (or is that with the
1.1.0-SNAPSHOT).
Anyway, I have tried building the trunk for OpenJPA from scratch to see
if I could use the 1.1.0-SNAPSHOT jars, but I the build fails. Are any
OpenJPA devs tuned in to this thread who can provide some inputs?
Thanks,
Rahul
Ming Fai Ma wrote:
hi,
I got exactly the same problem. My version is 1.1.0 snapshot on
2008-01-12, running JBoss 4.2.2 on JDK 6. By looking at the issue in
debug mode, it looks like Sun's InstrumentationImpl tries to lookup
the InstrumentationFactory at a top level classloader, but the OpenJPA
library is available only in a bottom level one (inside JBoss
UnifiedClassloader)
I just did a quick test to put the InstrumentationFactory package as a
jar to the JRE/lib/ext and I can get rid of the exception. And I also
did a debug trace and i found the exception is thrown from the
following piece of code:
org.apache.openjpa.enhance.InstrumentationFactory
vm.getClass().getMethod("loadAgent", new Class[] {
String.class }).
invoke(vm, new Object[] { agentPath }); // exception!
Not sure what would be the impact but I've patched the
InstrumentationFactory so that when it creates the temporary jar, it
writes the InstrumentationFactory class as well. The modified
InstrumentationFactory is attached.
What exactly is the InstrumentationFactory about?
regards,
mingfai
Reference:
private static String getAgentJar() throws IOException {
File file =
File.createTempFile(InstrumentationFactory.class.getName (),
".jar");
file.deleteOnExit();
ZipOutputStream zout = new ZipOutputStream(new
FileOutputStream(file));
zout.putNextEntry(new ZipEntry("META-INF/MANIFEST.MF"));
PrintWriter writer = new PrintWriter(new
OutputStreamWriter(zout));
writer
.println("Agent-Class: "
+ InstrumentationFactory.class.getName ());
writer.println("Can-Redefine-Classes: true");
writer.println("Can-Retransform-Classes: true");
writer.flush();
zout.closeEntry();
String strFilename =
"org/apache/openjpa/enhance/InstrumentationFactory.class";
zout.putNextEntry(new ZipEntry(strFilename));
InputStream in =
InstrumentationFactory.class.getResourceAsStream("/"
+ strFilename);
copy(in, zout);
zout.close();
return file.getAbsolutePath ();
}
On 1/12/08, *Rahul Thakur* <[EMAIL PROTECTED]
<mailto:[EMAIL PROTECTED]>> wrote:
Hi,
I am using OpenJPA 1.0.1 for a web application. When the web
application
starts up (Tomcat 6), the server logs show the stack trace below.
The trace is not really helpful as that class is there in the JAR
under
WEB-INF/lib directory, and google'ing didn't help either; so I am not
sure where to start investigating into this now :-(
Appreciate any pointers.
Thanks in advance,
Rahul
<snip>
DEBUG ArrayConverter - No conversion required, value is already a
java.net.URL[]
INFO StartupServlet - DTO <--> JPA entity registration completed!
DEBUG StoreModule - Configuring module:
com.google.code.cisx.store.StoreModule
java.lang.ClassNotFoundException:
org.apache.openjpa.enhance.InstrumentationFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass (ClassLoader.java:251)
at
sun.instrument.InstrumentationImpl.loadClassAndStartAgent(InstrumentationImpl.java:280)
at
sun.instrument.InstrumentationImpl.loadClassAndCallAgentmain(InstrumentationImpl.java
:348)
12/01/2008 22:15:30 org.apache.coyote.http11.Http11Protocol start
INFO: Starting Coyote HTTP/1.1 on http-8080
</snip>
