maven-dependency-plugin:copy tries to copy classes

I have parent pom and two module poms. In first module I want to copy second module (jar) to some folder. When I compiling project from first module pom - it works, but when I'm trying to compile from parent project pom, plugin tries to copy module classes insted of jar:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-dependency-plugin:2.1:copy (default) on project module1: Error copying artifact from /home/chardex/projects/test/module2/target/classes to /home/chardex/projects/test/module1/target/lib/classes: /home/chardex/projects/test/module2/target/classes (Is a directory) -> [Help 1]

   <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <executions>
            <execution>
                <phase>compile</phase>
                <goals>
                    <goal>copy</goal>
                </goals>
                <configuration>
                    <artifactItems>            
                        <artifactItem>
                            <groupId>...开发者_JS百科</groupId>
                            <artifactId>module2</artifactId>
                            <version>...</version>
                            <type>jar</type>
                        </artifactItem>
                    </artifactItems>
                </configuration>
            </execution>
        </executions>
    </plugin>

Thanks.

I believe this is a bug in maven-dependency-plugin: http://jira.codehaus.org/browse/MDEP-259

While doing this in eclipse, unchecking the "Resolve workspace artifacts" got rid of the error, and I could do a clean install successfully.

Check if you are using eclipse lifecycle mapping in your pom and if so, check the plugin version. For me, it was maven-dependency-plugin 2.1 (buggy) instead of 2.0 used by command line maven.

    <pluginManagement>
        <plugins>
            <!--This plugin's configuration is used to store Eclipse m2e settings 
                only. It has no influence on the Maven build itself. -->
            <plugin>
                <groupId>org.eclipse.m2e</groupId>
                <artifactId>lifecycle-mapping</artifactId>
                <version>1.0.0</version>
                <configuration>
                    <lifecycleMappingMetadata>
                        <pluginExecutions>
                            <pluginExecution>
                                <pluginExecutionFilter>
                                    <groupId>
                                        org.apache.maven.plugins
                                    </groupId>
                                    <artifactId>
                                        maven-dependency-plugin
                                    </artifactId>
                                    <versionRange>
                                        [2.0,2.0.8) <!-- 2.1 fails the build due to the http://jira.codehaus.org/browse/MDEP-187 -->
                                    </versionRange>
                                    <goals>
                                        <goal>
                                            copy-dependencies
                                        </goal>
                                    </goals>
                                </pluginExecutionFilter>
                                <action>
                                    <execute/>
                                </action>
                            </pluginExecution>
                        </pluginExecutions>
                    </lifecycleMappingMetadata>
                </configuration>
            </plugin>
        </plugins>
    </pluginManagement>