Is there a command that will let Maven use the Referenced Libraries when building a project?
See the Dependencies section of Maven / POM Reference:
The cornerstone of the POM is its dependency list. Most every project depends upon others to build and run correctly, and if all Maven does for you is manage this list for you, you have gained a lot. Maven downloads and links the dependencies for you on compilation and other goals that require them. As an added bonus, Maven brings in the dependencies of those dependencies (transitive dependencies), allowing your list to focus solely on the dependencies your project requires.
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I have a maven project imported into Eclipse Oxygen. Eclipse reports no compile issues (Alt + F5). When I run maven from the command line I get
[ERROR] /home/dean/src/TAP3UIs/TAP3Desktop/src/main/java/com/ms/tap3/controller/RequestAccessController.java:[8,30] package com.google.common.base does not exist
That package does exist in my .m2/repository in guava-15.0.jar. I can also see it in Eclipse mvn dependencies. When I check the mvn dependency:tree for the project I see
[INFO] | | | +- com.google.guava:guava:jar:15.0:runtime
It is a runtime transitive dependency on the command line, which explains why it doesn't compile on the command line. Somehow Eclipse has turned a transitive dependency from runtime to compile.
Does anyone know why this happens and how I make Eclispe m2e respect the scope of the transitive dependencies?
Currently, neither JDT nor m2e support multiple classpaths per project which is required to support different scopes.
See: Eclipse bug 486035 - Different classpath containers for different scopes
Update:
Since Eclipse Photon (4.8) which was released in June 2018 this is now supported. See Eclipse bug 526858 and my video showing this in action.
The main point is this: If you import external classes in your source code, you must set them as compile dependencies, and never trust the fact that they might already be transitive dependencies (because, since they are transitive, you have not direct control over them, so in a future version they might diseappear as well).
What is happening is this:
You need some classes from com.google.common.base package, so you need to set com.google.guava:guava:jar:15.0 as a dependency.
Instead, you didn't because you realised it was already a transitive dependency, but you missed the fact that is a runtime dependency.
Eclipse M2 does not distinguish the different Maven's standard classpaths, so it treats all dependencies as if they were of "compile" scope. So Eclipse includes guava-15.0.jar in the compilation and the project is compiled OK.
Maven, instead, won't include a runtime dependency in the compilation phase, so a compile error is raised.
In brief: You should include guava-15.0 (as well as any other artifact your code needs) as a direct dependency (with compile scope) in your pom file.
I have a plug-in project with several dependencies. Among them, there are a couple that are NOT in the official p2 Eclipse repository. They have been installed manually from its "private" update site.
Tycho can not compile the plug-in since it cannot find out where the local dependency is.
[ERROR] Missing requirement: es.uma.lcc.e-motions 2.0.1.qualifier requires 'bundle es.upv.dsic.issi.moment.mdt.maudedaemon 1.3.6' but it could not be found
These dependencies are jars in the eclipse/plugins folder. Can I add this folder as repository to my generated pom.xml?
I have a custom list of jars around 40 jars in a libs folder. I want to add all as a maven dependenices.
+ project
pom.xml
+ src
+ libs
Is there any way by that add all jar at a time.
Maven manages dependencies rather different than just including jars.
Essentially if you have a dependency on A and A uses B, you will need to have both A+B in your lib folder, but only A in your maven project, because maven transitively will include the subdependencies.
You should probably look through the maven repository, and see if you can find the jar files there in a similar version, and include that instead.
i.e. if you have commons-collections4-4.0.jar, use http://search.maven.org and write commons-collections4, and you will see a list of candidates. probably some with multiple version. Note, maven uses a groupId to scope jar files, so pick one with a suitable groupId, in this case org.apache.commons (Since commons-collections is an apache.org project).
When you have identified your dependency, it will show you ways to include it in your build, e.g. for maven, it would be
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-collections4</artifactId>
<version>4.0</version>
</dependency>
Looking at the pom file, you will be able to spot potential subdependencies, but otherwise, once you have added the dependency to your <dependencies/> section of your pom, run a mvn dependency:tree or mvn dependency:list to see how dependencies are transitively included.
Should you end up with libraries you cannot find in maven central, read this guide for the rest http://maven.apache.org/guides/mini/guide-3rd-party-jars-local.html
Found one wonderfull plugin to achieve this task. addjars-maven-plugin
I am building a Java (web) application with Maven and Eclipse.
When I look inside my .war file I can see the following logging libraries there:
log4j-1.2.14.jar
log4j-1.2.17.jar
slf4j-api-1.7.5.jar
slf4j-log4j12-1.7.5.jar
I did not declared these libraries in my pom.xml, so they probably are transitive dependencies (i.e. dependencies of my dependencies).
How can I find out which of my dependencies depend on these libraries?
I tried to use the mvn dependency:tree plugin, but it does not show any of these .jars.
In Eclipse, the Java Resources > Libraries > Maven Dependencies node does not show them either. Though, curiously, it shows other transitive dependencies of my project.
If you want to rely on maven only you may want to take a closer look on the dependency plugin, here are two examples:
mvn dependency:tree -Dverbose will display more detailed information - especially for example if a artifact will be omitted for conflicting with another artifacts version (e.g. convergence issue). It will also display you the hirachy with all the transitive dependencies.
To have a specific artefact analyzed (to for example find who delivers a specific transitive dependency) you can specify like so:
mvn dependency:tree -Dincludes=com.my.group.id:my-artefact-id:jar:1.0.1 -Dverbose
(Where you obviously need to adjust the artefact, packaging type and version according to your needs)
Open pom.xml in Eclipse and go to Dependency Hierarchy tab
![enter image description here][1]
It should show you the dependency tree in the Dependency Hierarchy tab. Evgeniy Dorofeev is right.
Something similar to the screenshot attached
you would probably have to expand all.
EDIT: Refined the answer.
Thats a little weird. But here is what i found.
If you go to http://mvnrepository.com/artifact/log4j/log4j/1.2.17
it will show you which dependencies are used and which does the jar file depend on.
The springframework dependency for web-mvc 3.2.4 would download the spring-core and the spring-core dependency uses log4j.
Eclipse Indigo; m2e 1.1.0; Maven integration for WTP 0.15.3; Maven 3.0.4
My web project has some dependency projects in the same workspace. All projects are installed. When i run maven install, except to see all dependencies in WEB-INF/lib.
When i run maven install plugin or maven war plugin, the WEB-INF/lib will be filled with dependencies, but they are a lot more than i expected, from the "dependency Hierarchy" or "Effective POM" view of the POM file, or from Maven dependencies in classpath view, i can not find the dependencies.
Run Maven->update projects does not help.
So where these dependencies come from or where should i start to debug?
EDIT
Previously my project has a large dependency tree(100+ jars), some of them are not needed, so i decided to remove them. My project depends on a common project, which has some not needed dependencies, i remove them from POM dependencies and run maven install for the whole projects dependency tree, success. then i run maven install on my project, it should not include the jars i removed from the common project, but, unfortunately they are there in WEB-INF/lib.
If you want to know where your dependencies are coming from, run:
mvn dependency:tree
from the command line. This shows how transitive dependencies are pulled in from your declared dependencies.
You can also run:
mvn dependency:analyze
to see if you can remove any unused dependencies to lessen the number of JARs packaged.
Problem solved, I delete the whole project and import from remote, run maven-install, it worked. Still have no idea why it not work before even after i run "maven clean install" on all dependency projects.