I had to add
<prefer-web-inf-classes>true</prefer-web-inf-classes>
to weblogic.xml to resolve a Hibernate antr compatibility issue with Weblogic. after adding that I was getting all different kind of classCastException related to XML parsers.
I understood from reading other threads that weblogic is trying to use a different class that what the application is expecting.
I spend all day researching and tried different solutions like removing "xml-apis......." jar files. but everytime I get ClassCastException. The cast "from" class changes when I remove jar files, but I always get
ClassCastException: "some xml parser related class" can not be cast to javax.xml.parsers.DocumentBuilderFactory
is there a way to know which xml parser jars are really causing the issue.
I m using Maven 2 to manage dependencies
Answering my own question:
I removed all jars that contains classes from javax.xml.* package by doing a java search and searching Package and check search in "application Libraries". then I had to remove sax..jar file. everything worked as expected after that.
Good answer to your own question. I also found this method (if you use maven), which generates a really nice dependency chart. I had this same problem, and using the dependency chart I was able to determine that the offending library, xml-apis*.jar, was loaded by maven as a dependency of jasperreports. Adding the exclusion element to the pom.xml for the jasperreports module fixed the problem.
http://maven.40175.n5.nabble.com/where-is-xml-apis-1-0-b2-jar-coming-from-td88057.html
Related
Recently I've been working on report generation with Jasper. I have created a simple program to test it and when running it via IDE it did work fine.
Then I moved the (very short) class to WildFly sever application and despite having the exact same code and library generation fails with cannot find symbol. Those symbols it cannot find are JREvaluator, JRFillVariable as well as packages such as net.sf.jasperreports.engine
In so far I have confirmed that:
Project builds (meaning those classes are visible for javac, but not jvm)
jasperreports-6.13.0.jar is added to war (it's present in /WEB-INF/lib folder alongside other libraries, like gson and hibernate
jasperreports-6.13.0.jar contains the missing classes
It looks to me like the problem doesn't lie in library not being loaded or missing classes (because in testing environment it works), but like something was preventing JBoss class loader from loading those classes
Attempted (and failed) solutions
Clean and Build
Adding -Djava.awt.headless=true to VM options - this did not changed anything
Adding -Djava.awt.headless=false to VM options - also didn't change a thing, but once caused NullPointerException inside jasperreport library. For testing program - worked in both cases
Adding commons-beanutils-1.9.4.jar, commons-digester-2.1.jar, commons-collections4-4.4.jar and commons-loggin-1.2.jar - with no changes
Adding jasper-compiler-jdt-5.5.23.jar - this caused a different error, namely NoSuchMethodError for org.eclipse.jdt.internal.compiler.ICompilerRequestor and few others. This library however should not be necessary as - from what I understand - jasperreport-6.13.0.jar already contains it's compiler and separate library for compiler is not required since a long time.
What has not been attempted:
Forcing the classes to load (http://www.java2s.com/Code/Java/Reflection/Forcethegivenclasstobeloadedfully.htm)
Dynamically loading jar during Runtime or using custom class loader
Update: after looking at this answer and applying the suggestion the missing class was different. Which suggests that the dependencies inside jasperreport.jar are not being loaded properly
I have figured it out
For some reason in server project libraries used by jasperreport.jar were not loaded, but in the testing project they were (might be due to WildFly, might be due to differences between IntelliJ and NetBeans)
Here is the list of libraries, based on pom.xml file in jasperreport.jar that I have added. Some might not be necessary and the list might not be exhaustive (I basically stopped adding libraries once report started generating) but it's good enough base if someone else runs into this problem:
commons-beanutils-1.9.4.jar
itext-2.1.7.jar
poi-ooxml-4.1.1.jar
commons-collections4-4.4.jar
jcommon-1.0.23.jar
xalan-2.7.2.jar
commons-digester-2.1.jar
jfreechart-1.0.19.jar
xmpcore-5.1.3.jar
commons-logging-1.2.jar
poi-4.1.1.jar
I'm started working on an already existing project. In this project there is some JSON-parsing happening with the following exception being thrown by several methods:
JSONException.class
While I was unit-testing these parsers I couldn't import the right org.json.JSONException library.
The maven library used in the codebase was (package org.json.JSONException):
org.json:json:20160810
And the one that was importing in my tests was (package org.json.JSONException):
com.vaadin.external.google:android-json:0.0.20131108.vaadin1
I think the problem lies in both libraries share the same package names. When the test is execute the JSONException is thrown but the test still fails because its probably the other library. Anybody knows why this problem is happening and how to solve it?
Thanks in advance!
I believe you need to updated your pom.xml file and in the dependency section you can exclude a 3rd party dependency from a declared dependency. I guess in your case there is a dependency to json and vaadin, you'll find vaadin is also pulling the different version of json.
You can try removing one of them. As suggested here:
https://github.com/spring-cloud/spring-cloud-deployer-kubernetes/issues/142
I am using several different schemas in my project. They are each compiled into a separate jar, each using a separate package, using the xmlbeans ant task. I can only seem to successfully parse xml (using the .Factory.parse(String xml) method) for the schema jar that is first in the classpath, otherwise I get a ClassCastException as described in this bug. If I change the jar ordering, a different schema will be able to parse successfully, and the ClassCastException will be thrown for a different class.
I've done some debugging, and I'm coming to the conclusion that the structure of the schemaorg_apache_xmlbeans.namespace package is probably responsible. Since my schemas do not have namespaces, each of jars I've built share some files that are identically named in identical packages. Specifically, I've seen that each jar has a schemaorg_apache_xmlbeans.namespace._nons.xmlns.xsb file that seems to point to the actual schema for that jar. If the factory uses this file to determine some of the classes it will use to parse the xml it has, this may explain the ClassCastException, as it's only looking at the first file on the classpath and not the correct one for the XML it has.
Whether there is any option to specify the namespaces for the schemas generated (like java namespaces) in the wsdls or xsds or in the ant task "wsdl to java" compilation?
I think the problem is that XMLBeans uses some kind of internal schema cache that mixes them up.
Have you tried giving your schemas (xsds) different namespaces?
This can be resolved by using the XMLOptions argument to the parse method.
Example:
XmlOptions opts = new XmlOptions();
opts.setDocumentType(YourDocument.Factory.newInstance().schemaType());
YourDocument.parse(String xml, opts);
see xmloptions.setDocumentType
I am importing a Jar file "com.ibm.mq.jar" into my workspace(Eclipse IDE).
While importing, a screen came where I could see all the classes in the Jar file.
After I imported it into the work space, I was able to import the package and following statement didn't give any error.
import com.ibm.mq.*;
But, in code I am not able to use any of the classes which were there in the package.
Like, "MQC" is a class in the package, but in code it doesn't reflect("MQC cannot be resolved as a type" error comes if I try to use it).
This jar file actually contains Websphere MQ API classes.
Can anyone advise, what am I missing.
If you're using MQ 7, check its documentation here. There was some stuff going on about deprecation of com.ibm.mq.mqc and, depending on the version you use, that class was replaced by com.ibm.mq.constants.MQConstants. Like this one, there are other cases.
In fact com.ibm.mq only contains the exception MQException, so you won't find any classes there. I suggest you check the version you're using and dig a little deeper into the docs, as a first step.
Has someone tried to use MessagePack with an Android app?
Is it possible? I have tried to use the Jar from msgpack-java and received the following Exception:
Caused by: java.lang.ExceptionInInitializerError
at org.msgpack.Packer.pack(Packer.java:532)
at org.msgpack.MessagePack.pack(MessagePack.java:31)
... 15 more
Caused by: java.lang.ExceptionInInitializerError
at org.msgpack.template.TemplateRegistry.<clinit>(TemplateRegistry.java:38)
... 17 more
Caused by: java.lang.VerifyError: org.msgpack.template.BeansFieldEntryReader
at org.msgpack.template.builder.BeansTemplateBuilder.<init (BeansTemplateBuilder.java:42)
at org.msgpack.template.builder.BuilderSelectorRegistry.initForJava(BuilderSelectorRegistry.java:73)
at org.msgpack.template.builder.BuilderSelectorRegistry.<clinit>(BuilderSelectorRegistry.java:38)
... 18 more
The code that I use is very simple
PrintWriter out = new PrintWriter(socket.getOutputStream());
Message msg = new Message();
msg.body = "asdasdasd";
msg.from = "qwe";
msg.to = "ttt";
byte[] bytes = MessagePack.pack(msg);
out.print(bytes);
out.flush();
I have javassist.jar, msgpack-0.5.2.jar, slf4j-api-1.6.2.jar and slf4j-jdk14-1.6.2.jar in my lib directory.
In my server application this code works fine with the same libraries.
(Hopefully) FINAL UPDATE
msgpack : 0.6.8 works on Android without any problems
msgpack-rpc : 0.7.0 works on Android with one caveat.
Specifically, you need to add the following to onCreate for API Level 8 (Android 2.2.1), and possibly lower:
java.lang.System.setProperty("java.net.preferIPv4Stack", "true");
java.lang.System.setProperty("java.net.preferIPv6Addresses", "false");
due to this bug.
If you want to see a simple example, here's a pair of projects set up for this purpose:
https://github.com/mikkoz/msgpack-android-test-server/tree/master/msgpack-android-test-server
https://github.com/mikkoz/msgpack-android-test-client/tree/master/msgpack-android-test-client
Previous Versions
UPDATE: as of 0.6.7 msgpack should be compatible with Android (there is a small dependency exclusion issue). Check the text below for msgpack-rpc (which also might be adapted in the future).
NOTE: If you're also using msgpack-rpc, you need to do the following steps:
Download the msgpack-rpc source from git://github.com/msgpack/msgpack-rpc.git (specifically, the "java" folder).
Change the main msgpack artifact version to the one you've built.
In org.msgpack.rpc.loop.netty.NettyEventLoop, change the NioClientSocketChannelFactory to OioClientSocketChannelFactory(getWorkerExecutor()).
Build the MessagePack-RPC in the same way as in the case of the main MessagePack JAR (see Step 11 above).
The NettyEventLoop replacement is due to this issue:
http://markmail.org/message/ypa3nrr64kzsyfsa .
Important: I've only tested synchronous communication. Asynchronous might not work.
And here's the reason for msgpack not working with Android prior to 0.6.7:
The reason for the error is that MessagePack uses several java.beans classes that are not included in the Android SDK. You're probably using the MessagePackBeans annotation.
This is a similar problem to the one described here, for which the general solution is outlined here. Unfortunately, in our case it requires a rebuild of msgpack. Here's what I did (you can almost certainly skip Steps 5 and 8, but I haven't tried it that way) :
Download the MessagePack source from https://github.com/msgpack/msgpack-java.git.
Import the MessagePack source as a project in your IDE.
Download the Apache Harmony source for the relevant packages from http://svn.apache.org/repos/asf/harmony/enhanced/java/trunk/classlib/modules/beans/src/main/java .
Copy these packages into your MessagePack project's src/main/java folder:
java.beans
java.beans.beancontext
org.apache.harmony.beans
org.apache.harmony.beans.internal.nls
In your MessagePack project, remove the following classes:
PropertyChangeListener
IndexedPropertyChangeEvent
PropertyChangeEvent
PropertyChangeListenerProxy
PropertyChangeSupport
Rename the java.beans packages to something different, e.g. custom.beans .
Change all java.beans references to the renamed ID, so again e.g. custom.beans. This applies especially to BeansFieldEntryReader (this class is the reason for the original error).
Change the custom.beans references for the five classes you removed in Step 5 back to java.beans.
In the org.apache.harmony.beans.internal.nls.Messages class, comment out the method setLocale, and remove the imports associated with it.
Remove all classes that still have errors, except Encoder. In that class, comment out all references to the classes you've removed. You should now have an error-free project.
Build the MessagePack JAR:
If you're using Maven, change the version in the pom.xml to something unique, run Maven build with the install goal, then add the dependency in your Android project with that version.
If you're not using Maven, you have to run the jar goal for Ant with the included build.xml. Replace the msgpack JAR in your Android project with this one.
If you're publishing your app, remember to include the relevant legal notice for Apache Harmony. It's an Apache License, just like MessagePack.
That should do it. Using your example code, and my own data class, I was successfully able to pack and unpack data.
The entire renaming ritual is due to the fact that the DEX compiler complains about java.* package naming.
There is a critical msgpack bug saying data packed with msgpack will get corrupted on the Dalvik VM. http://jira.msgpack.org/browse/MSGPACK-51
There is an ongoing effort by #TheTerribleSwiftTomato and the MessagePack core team to get MessagePack working on Android, please see the related GitHub issue. The fix mentioned in #TheTerribleSwiftTomato's answer is to be found here.
Update
I've managed to get it at least running on Android by (painstakingly) adding all the necessary javassist Classes which are currently required for the build to succeed. An extra 600KB gain in size, yet at least it seems to work. All in all, it appears to be working to some extent on Android, eventually check out the lesser-known resources about Message Pack such as its User Group and its Wiki for more information.
On a side-note, be sure to use a HTTP Request Library (such as LoopJ's Android Async HTTP or Apache's HttpClient) which can handle binary data.
Last but not least you can ping me if there is interest in this jar which makes MessagePack seemingly work on Android – credits go out of course to #TheTerribleSwiftTomato who supplied the fix above!
I suggest you write this in the main proguard-rules file-
-dontwarn org.msgpack.**
-keep class org.msgpack.** { *; }