I am currently migrating our build process from Eclipse/Ant to Maven/M2Eclipse/Artifactory.
I have a Webapp as a WTP project in Eclipse.
I have migrated it to Maven with m2eclipse.
The compilation runs fine from the Eclipse IDE.
However, when I try to compile from Maven CLI (mvn clean & mvn compile), Maven complains about not finding the libraries provided by the Tomcat Environment (like annotations-api, servlet-api, etc, ...).
Fair enough : Indeed, these dependencies are provided by WTP, as Java resources / Libraries / ApacheTomcat6. Maven is not aware of them.
I could deactivate this in the build path, and add each corresponding dependency in my POM, but I'm afraid this would lead Maven to deploy them again in my webapp (WEB-INF/libs).
So, what is the good way to say to maven "this application will run in a well known environment, providing the following libraries ". Is there some common Tomcat POM that I could add as a dependency ?
Thanks in advance for your advice.
regards,
Raphael
One way to handle this is to declare these dependencies with scope provided. These dependencies will be available for compile and test, but will not be packaged by maven into the webapp. For example,
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jsp-api</artifactId>
<version>2.0</version>
<scope>provided</scope>
</dependency>
Related
I'm trying to add the Eclipse Platform to my Maven project and stumbled over something very weird.
There is the plug-in org.eclipse.swt, which has a dependency org.eclipse.swt.${osgi.platform}, where ${osgi.platform} can be any of the following:
cocoa.macosc.cocoa
gtk.linux.aarch64
win32.win32.x86_64
However if you check the pom.xml of org.eclipse.swt.win32.win32.x86_64 you learn that this project has a dependency to org.eclipse.swt. Which forms a nice dependency circle, which is not allowed in Maven nor in OSGi.
Consequently I'm getting a StackOverflowError, but only if I try to use the maven-dependency-plugin with -Dosgi.platform=win32.win32.x86_64.
If I don't use that parameter I get the following exception:
No versions available for org.eclipse.platform:org.eclipse.swt.gtk.linux.aarch64:jar:[3.105.2,3.105.2]
(Which is probably okay, because I guess that Linux is the default value, but it doesn't apply to me, since I've got a Windows PC.)
I can't exclude the dependency either, e.g. with:
<dependency>
<groupId>org.eclipse.platform</groupId>
<artifactId>org.eclipse.swt</artifactId>
<exclusions>
<exclusion>
<groupId>org.eclipse.platform</groupId>
<artifactId>org.eclipse.swt.gtk.linux.aarch64</artifactId>
</exclusion>
</exclusions>
</dependency>
I get the same error messages as above with that approach.
I'm wondering how the Eclipse guys even managed to release that mess, but more importantly: How do I build against a Maven project with circular dependencies like this?
You're looking at the wrong place. Eclipse artifacts are published in Eclipse p2 repositories. In addition, some Eclipse artifacts will be published in Maven repositories for use in plain (non-Eclipse based) Java applications which cannot be used to build Eclipse-based applications. Something seems to have gone wrong publishing Eclipse SWT to Maven Central causing the circular dependencies. Please report this to Eclipse.
The Eclipse IDE packages are built with the Maven plug-in Tycho. See for example the pom.xml file for the Eclipse platform or here the parent pom.xml for all IDE packages. Tycho uses one or more Eclipse p2 repositories to resolve dependencies. A Maven repository would not work to resolve Import-Package dependencies or product configurations, for example. In a Maven repository, an artifact has a version, while in a p2 repository also Java packages of the same JAR can have different versions. In a Maven Tycho pom.xml only the p2 repositories have to be specified, the dependencies are already declared in the META-INF/MANIFEST.MF, feature.xml and *.product files.
In my pom.xml i have the following dependency
<dependency>
<groupId>org.codehaus.woodstox</groupId>
<artifactId>wstx-asl</artifactId>
<version>3.2.8</version>
</dependency>
My eclipse download the jar file as expected and my code compiles just fine. But when i execute my JUnit tests i'm gettin a exception wich is the cenario expected for when the dependency is missing.
If i change the dependency to
<dependency>
<groupId>org.codehaus.woodstox</groupId>
<artifactId>wstx-asl</artifactId>
<version>3.2.8</version>
<scope>system</scope>
<systemPath>\path\to\wstx-asl-3.2.8.jar</systemPath>
</dependency>
the issue persists. But when i remove the dependency from the pom.xml and add it to the builpath using the standard eclipse way everything works just fine.
Executing a mvn package the tests are executed just fine. Only when i run them in the eclipse envirionment that the issue occurs.
what am i missing here?
Eclipse has a separate build path. When using maven projects within Eclipse you need to rebuild the build path that Eclipse uses to point to the downloaded Maven artifacts.
You do this by running mvn eclipse:eclipse on your project and then clean and build your project from within eclipse.
This Maven plugin rebuilds your .classpath file within your project, this file stores your build path.
See: http://maven.apache.org/plugins/maven-eclipse-plugin/eclipse-mojo.html
I have just added dependencies to an eclipse project so that my jar can see other jars. How can I be sure that the dependencies work, and that what I've done is correct? I view a pom.xml file that has been created so what are the target folder and classes,test-classes subfolders used for? Thanks
If you have the m2eclipse plugin installed you can open your pom in Eclipse and click on the Dependency Hierarchy tab to view your resolved dependencies. You should manage all dependencies through Maven with the setup you are describing.
If you want to check command line you may want to look at using Effective Pom.
If you use m2e, it adds Maven Dependencies pseudo library to your project.
You may expand it and see if the dependent jar file is in there.
If it is, Eclipse ( or more precisely m2e ) has resolved the dependency correctly and it's available for you project build.
If you added your dependencies correctly your application should build and execute correctly, or am I missing something? Dependencies should be added to a POM section that looks like this example:
<dependencies>
<dependency>
<groupId>annogen</groupId>
<artifactId>annogen</artifactId>
<version>0.1.0</version>
</dependency>
<!-- other dependencies here -->
</dependencies>
Maven and the m2e/m2eclipse plugin rely on source files to be conventionally placed in src/main/java for application code and src/test/java for test code. Application code is compiled to target/classes and test code is compiled to target/test-classes. If you plan to use Maven and/or m2e/m2eclipse, do read about it. Maven: The Complete Reference is a good starting point.
I have a Eclipse project where Maven manages the dependencies. I have also few jar files that are not Maven enable and I locate them at src/main/webapp/WEB-INF/lib. I have no issue to build/run the project in Eclipse. I have no issue also to run "mvn:package" after I built the project in Eclipse. However, after I invoke "mvn:clean", if I run "mvn:package", I will get compilation error as it can't find dependency jar files under src/main/webapp/WEB-INF/lib. What I need to do is to rebuild the Eclipse project then "mvn:package". Therefore, I can't invoke "mvn:package" outside Eclipse IDE.
How to resolve this?
Thanks.
You have to put the not "Maven enabled artifacts" to an appropriate Maven Repository (Nexus, Artifactory what ever) and than change your project to use the dependencies appropriately. Furthermore either you do Maven or not but nothing in between. Maven is a build tool and not only for dependency management. After those changes working with Eclipse will work fine (if you use M2Eclipse). If you correctly use Maven you can do both things via Eclipse or call mvn package on command line.
If you can not set up a recommended environment (maven repository) you can add the dependencies as System dependencies to your pom.xml.
<project>
...
<dependencies>
<dependency>
<groupId>foo</groupId>
<artifactId>bar</artifactId>
<version>1.2.3</version>
<scope>system</scope>
<systemPath>${basedir}/src/main/webapp/WEB-INF/lib/foobar.jar</systemPath>
</dependency>
</dependencies>
...
</project>
I've created a Maven project and added the dependencies (jar files) that I need; however, netbeans says that it still cannot find it.
Specifically in my case, I added the jmf-2.1.1e.jar file into my dependencies folder. When I go back to my program it still gives me the compile error that it cannot find the javax.media package.
Did you let Netbeans manage the dependency?
In your "Projects" listing, find and context+click on the "Dependencies" folder in the list. From the context menu, choose "Add Dependency".
This approach works at least in NetBeans 7.4 and 8.0 beta.
Make sure that your pom.xml has the following snippet that defines the dependency
<dependencies>
<dependency>
<groupId>javax.media</groupId>
<artifactId>jmf</artifactId>
<version>2.1.1e</version>
</dependency>
</dependencies>
The dependency is available in Maven Central. Add the pom snippet manually to the pom.xml and run Maven in the shell and let it download the dependency. This should resolve your issue.
Maven automatically downloads the dependency once specified in the pom.xml. For this you would have to build your project with the dependency as specified by Tim Sparg.