I am trying to follow this SO question which uses a Jetty ServletTester class.
I have spent all morning trying to locate the JAR that houses ServletTester to no avail. Even pulling down the aggregated "all JAR" doesn't turn up a *.testing package with that class in it. See for yourself, do a Maven/Gradle resolve for:
compile 'org.eclipse.jetty.aggregate:jetty-all-server:8.1.14.v20131031'
Even in their source code on GitHub it looks like there isn't a testing subproject, yet, in those JavaDocs above, it seems to exists somewhere...
Does anybody know where I can find the JAR that houses this class? If so, what is it, where/how do I acquire this JAR, and what did you do to figure this out (so I don't need to ask these types of questions again!)?
According to Maven Central, this class can be found in org.eclipse.jetty:test-jetty-servlet:8.1.16.v20140903:jar
Add the following dependency:
<dependency>
<groupId>org.eclipse.jetty</groupId>
<artifactId>test-jetty-servlet</artifactId>
<version>8.1.16.v20140903</version>
</dependency>
Also, you can use sites like Maven Central's find artifact by class name feature.
Related
I have a pom.xml where i've got hadoop-core dependency as provided
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-core</artifactId>
<version>${hadoop.version}</version>
<scope>provided</scope>
</dependency>
When I add cfg4j as compile time dependency
<dependency>
<groupId>org.cfg4j</groupId>
<artifactId>cfg4j-core</artifactId>
<version>4.4.0</version>
</dependency>
<dependency>
<groupId>org.cfg4j</groupId>
<artifactId>cfg4j-consul</artifactId>
<version>4.4.0</version>
</dependency>
I've got an exception "java.lang.NoSuchMethodError: javax.ws.rs.core.Response.someMethod". I've investigated the problem and find out that the problem is from hadoop and cfg4j-consul. Hadoop core depends to jersey-core and cfg4j depends on cxf. Both declared javax.ws.rs as dependecy so the problem is that jersey has version 1.1 and cxf has 2.0.2. Hadoop dependency is provided, cause it's needed by Flink (framework) and it's in the lib folder. I can't just upgrade it or remove it, nor add it as compile time and exclude the lib. Even I was able to do it, I have no guarantees that hadoop will work as expected. I guess shading doesn't fix the problem cause it's not with cfg4j but one of the dependency of his dependency.
Is there way to resolve the conflict? Does gradle has it's onw ways to fix such issue?
Two approaches:
Shading: A bit more difficult as you say because this a transitive dependency, but I would have a look a Maven shade plugin and it would still be possible to declare the dependency directly if necessary.
Don't use the dependency and try to find some other library or solution for your problem.
Try the following steps, here is the source: https://reflectoring.io/nosuchmethod/
Your issue has nothing to do with the choice between Mavern and Gradle, switching therefor will not help.
Fixing a NoSuchMethodError
There are a lot of different flavors of NoSuchMethodErrors, but they all boil down to the fact that the compile time classpath differs from the runtime classpath.
The following steps will help to pinpoint the problem:
Step 1: Find Out Where the Class Comes From
First, we need to find out where the class containing the method in question comes from. We find this information in the error message of the NoSuchMethodError:
Exception in thread "main" java.lang.NoSuchMethodError:
io.reflectoring.nosuchmethod.Service.sayHello(Ljava/lang/String;)Ljava/lang/String;
Now, we can search the web or within the IDE to find out which JAR file contains this class. In the case above, we can see that it’s the Service class from our own codebase and not a class from another library.
If we have trouble finding the JAR file of the class, we can add the Java option -verbose:class when running our application. This will cause Java to print out all classes and the JARs they have been loaded from:
[Loaded io.reflectoring.nosuchmethod.Service from file:
/C:/daten/workspaces/code-examples2/patterns/build/libs/java-1.0.jar]
Step 2: Find Out Who Calls the Class
Next, we want find out where the method is being called. This information is available in the first element of the stack trace:
Exception in thread "main" java.lang.NoSuchMethodError:
io.reflectoring.nosuchmethod.Service.sayHello(Ljava/lang/String;)Ljava/lang/String;
at io.reflectoring.nosuchmethod.ProvokeNoSuchMethodError.main(ProvokeNoSuchMethodError.java:7)
Here, the class ProvokeNoSuchMethodError tries to call a method that does not exist at runtime. We should now find out which library this file belongs to.
Step 3: Check the Versions
Now that we know where the NoSuchMethodError is provoked and what method is missing, we can act.
We should now list all of our project dependencies.
In Gradle, we can call:
./gradlew dependencies > dependencies.txt
If we’re using Maven, a similiar result can be achieved with:
mvn dependency:list > dependencies.txt`
In this file, we can search for the libraries that contain the class with the missing method and the class that tries to call this method.
Usually we’ll find an output like this somewhere:
\--- org.springframework.retry:spring-retry:1.2.2.RELEASE
| \--- org.springframework:spring-core:4.3.13.RELEASE -> 5.0.8.RELEASE
The above means that the spring-retry library depends on spring-core in version 4.3.13, but some other library also depends on spring-core in version 5.0.8 and overrules the dependency version.
We can now search our dependencies.txt file for 5.0.8.RELEASE to find out which library introduces the dependency to this version.
Finally, we need to decide which of the two versions we actually need to satisfy both dependencies. Usually, this is the newer version since most frameworks are backwards compatible to some point. However, it can be the other way around or we might even not be able to resolve the conflict at all.
After upgrading gwt from version 2.1.1 to 2.8.0, I got the error message
2017-04-20 12:59:19.551:WARN:oejuc.AbstractLifeCycle:main: FAILED c.g.g.d.s.j.WebAppContextWithReload#341fbaf1{/,file:/C:/Users/xxx/.IntelliJIdea2017.1/system/gwt/xxx.97baa614/xxx.fdf824a8/run/www/,STARTING}{C:\Users\xxx\.IntelliJIdea2017.1\system\gwt\xxx.97baa614\xx.fdf824a8\run\www}: java.util.ServiceConfigurationError: org.apache.juli.logging.Log: Provider org.eclipse.jetty.apache.jsp.JuliLog not a subtype
java.util.ServiceConfigurationError: org.apache.juli.logging.Log: Provider org.eclipse.jetty.apache.jsp.JuliLog not a subtype
I found some other posts with similar messages, like this or this, but the situation seems to be different:
I do not use Maven or Ant, just pure IntelliJ, I have no reference to any Tomcat library, and I am not aware of any JSP in our application.
I found through debugging that first the class loader com.google.gwt.dev.shell.jetty.Jettylauncher$WebAppContextWithReload$WebAppClassLoaderExtension loads class org.eclipse.jetty.apache.jsp.JuliLog including interface org.apache.juli.logging.Log.
Then, later interface org.apache.juli.logging.Log is loaded by sun.misc.Launcher$AppClassLoader triggered indirectly by
org.eclipse.jetty.webapp.WebAppContext.startContext()
which calls method initialize of an
org.eclipse.jetty.jsp.JettyJspServlet
instance.
I have no idea why a JspServlet needs to be initialized at all, as no JSPs are used in the application, as far as I see, just a few Servlets. And it seems all the classes involved in this conflict are contained in the single jar gwt-dev.jar, so I see no possibility to influence any class loading behavior via class path settings.
Any idea how I could resolve this?
I also got this error upgrading from gwt from version 2.4 to 2.8.2.
Jake W's answer helped me.
To solve this, I ran a maven dependency tree on my project to figure out what was referencing jetty's apache-jsp.
To run the dependency tree, in Eclipse I created a new run configuration -> maven build -> with the goals "dependency:tree -Doutput=/dependency/file.txt". Once it's run, the console output will show where it saves the output. It should be the same location that you referenced with the -Doutput option.
Look for something like this in the output file:
- org.eclipse.jetty:apache-jsp:jar:9.2.14.v20151106:compile
And then look up in the tree to see where it's being pulled in from. In my case it came from this:
+- com.google.gwt:gwt-dev:jar:2.8.2:compile
+- net.sourceforge.htmlunit:htmlunit:jar:2.19:compile
\- org.eclipse.jetty:apache-jsp:jar:9.2.14.v20151106:compile
Once you know where it's coming from, (assuming you're using maven) you can add an exclusion in your pom.xml file for it:
</dependencies>
<dependency>
<groupId>com.google.gwt</groupId>
<artifactId>gwt-dev</artifactId>
<version>${gwt.version}</version>
<exclusions>
<exclusion>
<groupId>org.eclipse.jetty</groupId>
<artifactId>apache-jsp</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
This worked for me. Thanks :)
I saw this error when I recently upgraded to GWT 2.8.0. Please try to exclude jetty-apache-Jsp related dependencies from your project.
You may see other jetty related issues as well, so please also make sure you are using exactly the same jetty version as GWT 2.8.0 is using.
I'm on mobile at the moment, unable to add more details, but I hope that can be a useful direction to go. Please add your comments if you still see issues, I will then have a look and update the answer when I'm on my laptop.
I have just ran into this exception after adding gwt-test-utils:0.53 dependency (with GWT 2.8.1)
I am using ant and all information found regarding this error indicated there was 2 versions of Juli Logging in the classpath, but every search came up with only gwt-dev.jar. Production builds worked fine, but dev mode did not which needs gwt-dev.jar.
Part of the build process has the jars copied from a local lib directory to war/WEB-INF/lib to pack into the war. The ant script points to the local lib directory for debugging, not the ones meant for the war file. Despite the war location not being listed in the ant file as a class path, it was still loading it.
Ultimately, gwt-dev.jar was conflicting with the copied version of itself.
If I check my effective pom I will find the following entry:
<dependency>
<groupId>com.package.of.other.department</groupId>
<artifactId>someArtifact</artifactId>
<version>2.4.2</version>
<scope>provided</scope>
</dependency>
This comes from the parent pom that we have to use to let our software (bpmn processes) run on a company wide platform.
Now comes a hacky part. There will be a bigger change and we cannot use someArtifact anymore. Unfortunately that artifact gets called directly by all our processes (you design the process and configure the full qualified class name for an item) and can't just configure a different artifact, as that would most likely break a lot of the running processes.
The simple plan was to create a class with the same package name and with the same class name, remove every dependency to the original package and everything should work fine. During the tests I noticed that it doesn't use my new class but still the original one, most likely because it gets provided as dependency via the mandatory parent pom and for some reason prefers that over my local one.
Excluding a provided dependency from the parent pom doesn't seem to work that easily?! Any idea how I could solve my issue?
If the application is regular java, the class that will be load is the first class met in the classpath order.
If you use other runtime package dependency management, the strategy is different. As example you can adjust your import-package in OSGi to ensure the use a class contains in private-package.
I am having trouble in figuring out which jar does WebClient class belongs.
In CXF 2.7 it was in cxf-bundle.jar, but in 3.0.7 I am unable to find it. I've been looking up jars for 2 hours but couldn't get anything.
Thanks!
I'll post my comment as answer:
Please take a look at:
org/apache/cxf/cxf-rt-rs-client/3.0.7/cxf-rt-rs-client-3.0.7.jar
I found this JAR by searching http://mvnrepository.com/ for WebClient-Artifact ID (which i found in the API-Docs for CXF):
<dependency>
<groupId>org.apache.cxf</groupId>
<artifactId>cxf-rt-rs-client</artifactId>
<version>3.0.0-milestone1</version>
</dependency>
EDIT:
To find JAR's for specific packages, in most cases google is your friend:
Just google for (for example) org.apache.cxf.transport.servlet.CXFNonSpringServlet
But you can also search/analyze your local JAR's for this String (most ZIP-Tools support searching inside of ZIP/JAR-Files).
I was getting the error package org.apache.cxf.jaxrs.client does not exist,
Added dependecy
org.apache.cxf cxf-rt-rs-client 3.0.0-milestone1
issue resolved
I'm trying to write a plugin into a framework application (Joget). My plugin source looks something like this:
public class MyPlugin extends ExtDefaultPlugin implements ApplicationPlugin, ParticipantPlugin {
...
public void execute(){
...
SecurityContextImpl secContext = (SecurityContextImpl) WorkflowUtil.getHttpServletRequest().getSession().getAttribute("SPRING_SECURITY_CONTEXT");
}
}
When I run the plugin, I get the following exception.
java.lang.ClassCastException: org.springframework.security.context.SecurityContextImpl cannot be cast to org.springframework.security.context.SecurityContextImpl
I'm using Maven. Now since both have the same package name, I'm assuming I'm accidentally using the wrong package version in my plugin JAR (that contains the SecurityContextImpl class) than the one in the framework. But I've double-checked and it looks like I'm including the correct one in my plugin package.
Is there a way to see the classloader or source JAR of my class (e.g. using reflection in some manner)? Any other ideas on how to address this?
This type of java.lang.ClassCastException, where both classes names are equals, occur when the same class, or two class with the same name are loaded by 2 different classloaders.
I don't know Joget, but you are talking about plugin. Frameworks often load plugins in separate classloaders to ensure a proper isolation between them.
Since you say I've double-checked and it looks like I'm including the correct one in my plugin package., you may want to remove spring-security from your package, as it's probably already loaded by the framework classloader.
You're using Maven, so you may simply add <scope>provided</scope> to the spring-security dependency (but not sure, since we don't have your pom.xml)
I've got the same exception when I was running my plugin.
There are two cases in general:
1. The class is a local class.
And that is to say, there is no repository(groupId, artificateId, etc) to be deployed in the pom.xml of your plugin. The solution is, go the target folder and open the xxx-0.0.1-snapshot.jar file, then open META-INF/MANIFEST.MF, add the source file of that class /dependency/file.jar, then add the source jar to the dependency folder
Remarks: It is better to give a version of the your local file and add it as shown in your pom.xml to let it be found as src in your code.
<!-- your source jar need to be renamed as example-1.0.0.jar -->
<dependency>
<groupId>this.should.be.the.prefix.of.your.package</groupID>
<artificateId>file.name<artificateId>
<version>1.0.0</version>
<systemPath>${basedir}/lib/stclient_updated-1.0.0.jar</systemPath>
<scope>system</scope>
</dependency>
2. The class is a remote class with repository
I had this type of problem once because the repository is not correct, see also Maven Repository to find the official repository of the source.
I hope that it could help =)
Cheers