Maven not downloading dependency for org.eclipse.persistence

[Eric Lopez-Fernandez]

Hey there,

I am having trouble with maven. I do have the following POM.xml file

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" 
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
         http://maven.apache.org/xsd/maven-4.0.0.xsd">

    <modelVersion>4.0.0</modelVersion>
    <groupId>com.apress.javaee6</groupId>
    <artifactId>chapter02</artifactId>
    <version>2.0</version>
    <name>chapter02</name>

	<dependencyManagement>
		<dependencies>
			<dependency>
				<groupId>org.eclipse.persistence</groupId>
				<artifactId>javax.persistence</artifactId>
				<version>2.0.0</version>
			</dependency>
			<dependency>
				<groupId>org.eclipse.persistence</groupId>
				<artifactId>eclipselink</artifactId>
				<version>2.0.0</version>
			</dependency>
			<dependency>
				<groupId>org.apache.derby</groupId>
				<artifactId>derbyclient</artifactId>
				<version>10.8.1.2</version>
			</dependency>			
			<dependency>
				<groupId>org.apache.derby</groupId>
				<artifactId>derby</artifactId>
				<version>10.8.2.2</version>
			</dependency>
			<dependency>
				<groupId>junit</groupId>
				<artifactId>junit</artifactId>				
				<version>4.8.1</version>
				<scope>test</scope>
			</dependency>				
		</dependencies>
	</dependencyManagement>
		
	<repositories>
		<repository>
			<id>EclipseLink Repo</id>			     
			<url>http://download.eclipse.org/rt/eclipselink/maven.repo/</url>                 		
			<snapshots>
				<enabled>true</enabled>
			</snapshots>			
		</repository>
	</repositories>	
	
    <build>
		<pluginManagement>
			<plugins>
				<plugin>
					<groupId>org.apache.maven.plugins</groupId>
					<artifactId>maven-compiler-plugin</artifactId>
					<version>2.5</version>
					<inherited>true</inherited>
					<configuration>
						<source>1.6</source>
						<target>1.6</target>
					</configuration>
				</plugin>		
			</plugins>
		</pluginManagement>
    </build>
</project>

And here is the error message I'm getting

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:2.5:compile (default-compile) on project chapter02: Compilation failure: Compilation failure:
[ERROR] ~\05292012\src\main\java\Book.java:[3,0] package javax.persistence does not exist

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

It seems like maven was not able to download the dependency for org.eclipse.persistence

Has somebody had that problem before?

Any help will be greatly appreciated!
Eric

[E Armitage]

If mvn failed to download something you usually get an error message stating that fact. Are there any other error messages before the one you posted?

[Eric Lopez-Fernandez]

Thank you for your reply E Armitage!

That is the first error message. If I go to ~\.m2\repository I am not able to find anything related to org.eclipse.persistence, however I am able to find stuff related to maven-compiler-plugin

I was wondering if the problem is with the repository that I'm specifying or with the version number for the dependencies. Do you have any idea?

[James Boswell]

I don't think that URL for the EclipseLink repo exists anymore.

Have you tried the repo at java.net instead?

<repositories> <repository> <id>java.net-Public</id> <name>Maven Java Net Snapshots and Releases</name> <url>https://maven.java.net/content/groups/public/</url> <updatePolicy>never</updatePolicy> </repository> </repositories>

[Peter Johnson]

Try removing the <dependencyManagement> tags. That is, delete lines 13 and 42.

Because you are getting a compiler error, the problem you are having is not with downloading artifacts. Instead, the issue is that the compiler classpath doesn't include the JARs that you need. I think that the <dependencyManagement> tags are causing this, hence my suggestion to remove them. One way to check this is to use the -X option and observe what the compiler classpath gets set to.

[Eric Lopez-Fernandez]

The problem was fixed by removing the <dependencyManagement> tag. Somehow it was not allowing to download everything.

Thank YOU all for your help!

[E Armitage]

Eric Lopez-Fernandez wrote:
.. Somehow it was not allowing to download everything.

The explanation (which is always better than the solution) has already been given.
DependencyManagement doesn't state what your artifact depends on and so doesn't state what requires to be downloaded so no download was being done.
It specifies versions so that if you do add dependencies to your project then the project doesn't have to specify the versions since they are already in DependencyManagement.
When you add the actual dependencies the should not be under DependencyManagement.

[Eric Lopez-Fernandez]

Thank you very much for the explanation, I appreciate that!