I was trying to add some Java Libraries (AWS SDK for Java, Apache Commons Math, etc.) to my Grails project since some of my Java source code (placed in src/java) had dependencies. By following this answer, I was able to resolve compile errors by adding the jar files to the /lib folder and add it to the build path, as answered here: Add Java Libraries to a Netbeans Grails Project
However, when I call my Java source code from my controller during runtime, it is unable to find the Java libraries that I added, showing a NoClassDefFoundError. Should I be adding something to the BuildConfig.groovy file? I'm not sure what the name convention for the jar files to be added to the dependencies.
The question you refer to is 5 years old. You should use newer resources :)
The preferred approach now is to use dependencies in BuildConfig.groovy, and let Grails (via Ivy or Maven) download the jars for you once and reuse them for various projects.
It's not always obvious what the syntax is, and I find that http://mvnrepository.com/ is a great resource. For example if you search for "commons math" and click through to http://mvnrepository.com/artifact/org.apache.commons/commons-math you'll see a few versions. Click on version 2.2 and you'll see the Maven dependency XML but you can click on the Gradle tab and it's going to be similar to what you need for Grails. So I'd add
dependencies {
compile 'org.apache.commons:commons-math:2.2'
}
and if necessary change compile to runtime, build, etc. depending on what you need the jar in the build process.
In the rare case that you do have a jar that isn't available in a Maven repo (e.g. a shared library at your company) then you can put the jar file in the lib directory. As you've seen, Grails doesn't auto-detect it (this is as of version 2.0). But you can run grails compile --refresh-dependencies to get your jar added to the classpath.
My issue turns out to be the fact that AWS Java SDK had dependencies (Apache HTTP Client) that were not installed yet and that I was unaware of.
This is what I had to configure this for my BuildConfig.groovy file
dependencies {
runtime 'org.apache.httpcomponents:httpclient:4.2.5'
runtime 'com.amazonaws:aws-java-sdk:1.4.7'
}
All the dependencies for AWS Java SDK 1.4.7 can be found here: http://mvnrepository.com/artifact/com.amazonaws/aws-java-sdk/1.4.7. All the dependencies outside of HTTP client were already installed for me, but may not be for your Grails setup.
Related
I've successfully used Grails's inline / inplace plugin notation to develop my Grails app and several plugins concurrently. I only have to compile my Grails app and all the inline plugins get compiled too (great!):
grails.plugin.location.myFooPlugin = '../plugins/foo-plugin'
Can I do the same thing for a Java dependency rather than a Grails plugin?
Let's say I have some Java project that ultimately produces a JAR, but rather than compile and store the JAR in my Maven local repo I'd like to simply compile my Grails app and have the Java project's code also compiled as a result. Possible? If so, what are the rules, such as dir structure adherence? I might want to use Gradle or Maven, not sure.
I'm using a java dependency in my Grails project with help of /scripts/_Events.groovy:
eventCompileStart = {
projectCompiler.srcDirectories << "${basedir}/../your_java_proj/src".toString()
}
The java project will be compiled automatically along with e.g. grails war commando.
I have an app in Grails that uses a .java to manage paypal MassPay feature. Like many .java, it needs some jars that enclose the classes that jar uses. Ok, i import that jars and the errors in the .java dissapears. But now, when I try to run the app, i receive 25 messages like this:
myapproute/grails-app/controllers/com/mycompany/widget/MassPay.java:3: package com.paypal.sdk.profiles does not exist
import com.paypal.sdk.profiles.APIProfile;
That file in the MassPay.java does not throw any error, since i imported the jar where that class is enclosed. But it doesn't allow me to run the project.
Any help? thanks.
Im using Eclipse, not NetBeans (i have read that there is a bug in Netbeans)
Adding JARs to the Eclipse project build path is not sufficient to make them visible to Grails. You need to either put them in the application's lib directory and run grails compile --refresh-dependencies or (better) if the JARs are available in a Maven-compatible repository simply declare your dependencies in BuildConfig.groovy and let Grails download the JARs itself.
Run this - it will work
grails clean
I have a Grail application that references a Java library (as an IntelliJ Module dependency). This works, but as soon as I add hibernate as a dependency of the Java library the Grails will no longer run.
Loading Grails 2.0.1
Error Error executing script RunApp: Provider for javax.xml.parsers.SAXParserFactory cannot be found (Use --stacktrace to see the full trace)
In my Java module, I am adding hibernate with the following:
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.0.0.Final</version>
</dependency>
I can't see any good way around this. The Grails dependency-report does not show any libraries in conflict. The error occurs if the hibernate plugin is installed in the Grails application or not.
Bear in mind that (in this case) the Java library is not being incorporated via the BuildConfig.groovy. It is being incorporated as an IntelliJ Module dependency. If I incorporate the module as a jar via BuildConfig.groovy, everything works, but I lose the ability to step into the Java code.
Clarifying:
Per the JetBrains folks, the Java library is incorporated both as an IntelliJ Module dependency and in the BuildConfig.groovy. When executed from the command line, the project works, this is only an issue when starting from the IDE.
Suggestions?
Return dependency to java library to BuildConfig.groovy and use last version of IDEA: http://confluence.jetbrains.net/display/IDEADEV/IDEA+11.1+EAP . Navigation should work fine.
After experimentation, I stumbled upon the following which seems to be working very well (at least in IDEA 11.1):
Your Java library JAR should be referenced from the
BuildConfig.groovy (we use Maven, so we had to add the local Maven
repo as well)
Also reference your modules as module dependencies of the Grails module
(this is critical) in the run config for your grails project, uncheck the "add --classpath ..." option
The module dependency gives you:
Immediate awareness of the Java classes and their methods from the Grails project
Support for stepping into the Java code from your Grails project.
The BuildConfig reference gives you:
support for the grails commands, including run-app (which is how IntelliJ kicks things off when running/debugging a project)
If you leave the --classpath option checked, then you foul up the way that grails resolves its dependencies. There may be a better way to do this, but I haven't found it.
Additional Note
There's a bug in the interaction of grails and maven which causes grails to not pull in dependencies from local Maven 3 repositories if the pom.xml wasn't changed.
Therefore, our complete dependency refresh cycle looks like:
goto top
mvn clean install
find the relevant POM files in the repo and touch them
back to grails app directory and grails refresh-dependencies
run the app
You only need to do this when there are updates to the upstream Java libraries.
Hat tip to Sergey from Jet Brains for tracking that one down.
I'm working with IntelliJ IDEA 10.0.1 and Grails 1.3.7. I have a mavenized Grails project which depends on many logging libraries.
Here's the problem:
I have to use JCL as logging framework, but grails per default is working with SLF4J and has some default dependencies like jcl-over-slf4j, which are inherited by every grails project. First of all I have excluded every jcl-over-slf4j transitive dependency in my project pom file and verified with mvn dependency:tree that my pom is clean of any SLF4J bridging libraries.
But nevertheless jcl-over-slf4j is still beeing downloaded to my local maven repo when I try to start my grails app. This leads obviously to a StackOverflowError at runtime, since both jcl-over-slf4j and slf4j-jcl are in the classpath.
So because of which declaration the jcl-over-slf4j dependency is still beeing downloaded?
Since my pom is clean the obvious conclusion would be that Grails itself depends on those libraries. As mentioned before Grails has some default dependencies, on which every Grails project depends.
I know that I can exclude inherited depencencies in the BuildConfig.groovy file and if I run grails dependency-report I can also see that these dependencies are not listed anymore.
grails.project.dependency.resolution = {
inherits("global") {
excludes "jcl-over-slf4j", "jul-to-slf4j", "slf4j-log4j12"
}
}
But even then the jcl-over-slf4j dependency is still beeing downloaded to my repo when I start my grails app! Am I missing something? Is there a different way to exclude inherited grails dependencies when you're using a mavenized grails project?
Any help would be appreciated
Thanks!
Slash
Ok I think I got the answer now..
The problem is that the defined maven-grails-plugin (which is mandatory when you use maven + grails) within my pom file depends on jcl-over-slf4j and therefore gets downloaded when I start my application through maven. With my current maven version (2.2.1) it's not possible to exclude a dependency from a plugin. There is also a jjira issue regarding this problem. Can not exclude a dependency from a plugin
As soon as I remove the maven-grails-plugin the dependency is not downloaded anymore, but as drawback I'm not able to start the application through maven anymore..
Lessons learned: Don't use Maven + Grails + JCL in conjunction.
Note that with mvn dependency:tree just project dependencies are listed, but plugin dependencies are NOT listed.
Hope this is of any help!
Regards Slash
I recently upgraded a project to Grails 1.3.5. This deleted everything in the /lib dir, though the project continues to work, so I guess the way dependencies are specified (and the location they're stored) has changed. I want to remove some libs that I'm no longer using, but can't do this until I find where the dependencies are specified.
Thanks,
Don
I'm surprised that anything was deleted from your lib directory - that shouldn't happen.
Dependencies are registered in BuildConfig.groovy in your app and in the plugins that work with Grails 1.2 and above. Older plugins will continue to have jars in their lib directories which will be added to the classpath, and you can still do the same. Obviously it's best to use the dependency management if possible so you have just the one copy of the jar in your Ivy cache instead of one for every project on your machine.
You can run grails dependency-report to generate Ivy reports to see what's managed by Ivy in each environment. These will end up in target/dependency-report and there's no index file, so just open any of the .html files and you can navigate to the others from there, e.g. target/dependency-report/org.grails.internal-{appname}-runtime.html.