Basic maven plugin project not working, Mojo plugin descriptors not generating
I am following the tutorial for creating a maven plugin and cannot run mvn install without getting errors. The info complains that i don't have the required mojo descriptors when the annotations should be generating them for me. I am running maven 3.0.5 and using intellij as my ide. here is my Main class:
@Mojo(name = "modify-connector")
public class ComplianceMojo extends AbstractMojo {
@Parameter
private String artifactId;
@Parameter
private String version;
@Override
public void execute() throws MojoExecutionException, MojoFailureException {
File jar = new File(getPluginContext().get("project.build.directory") + "/"
+ getPluginContext().get("project.build.finalname") + "/" + artifactId + "-" + version);
if(jar.exists()){
getLog().info("The file exists! " + jar.getAbsolutePath());
} else {
getLog().info("The file does not exist: " + jar.getAbsolutePath());
}
}
}
And here is my pom.xml
<?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>mysql-jdbc-compliance-maven-plugin</groupId>
<artifactId>mysql-jdbc-compliance-maven-plugin</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>maven-plugin</packaging>
<dependencies>
<dependency>
<groupId>org.apache.maven</groupId>
<artifactId>maven-plugin-api</artifactId>
<version>2.0</version>
</dependency>
<dependency>
<groupId>org.apache.maven.plugin-tools</groupId>
<artifactId>maven-plugin-annotations</artifactId>
<version>3.2</version>
<scope>provided</scope>
</dependency>
</dependencies>
</project>
Note: I had to separately add the annotations dependency as the main plugin api did not contain these classes. when i run mvn install on my project, the output is as follows:
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.867s
[INFO] Finished at: Wed Sep 25 17:45:55 EST 2013
[INFO] Final Memory: 8M/244M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-plugin-plugin:2.9:descriptor (default-descriptor) on project mysql-jdbc-compliance-maven-plugin: Error extracting plugin descriptor: 'No mojo definitions were found for plugin: mysql-jdbc-compliance-maven-plugin:mysql-jdbc-compliance-maven-plugin.' -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException
Solution 1:
Maybe this is related to a unresolved issue in Maven: https://issues.apache.org/jira/browse/MNG-5346
For my plugin projects, i could workaround by adding an explicit execution of the maven-plugin-plugin:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-plugin-plugin</artifactId>
<version>3.2</version>
<configuration>
<!-- see http://jira.codehaus.org/browse/MNG-5346 -->
<skipErrorNoDescriptorsFound>true</skipErrorNoDescriptorsFound>
</configuration>
<executions>
<execution>
<id>mojo-descriptor</id>
<goals>
<goal>descriptor</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
But see the comments in the JIRA issue for more elaborate solutions!
Solution 2:
after reading the Jira Issue that Gyro posted, i added the following lines to my pom and everything compiled nicely.
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-plugin-plugin</artifactId>
<version>3.2</version>
<configuration>
<goalPrefix>mysql-jdbc-compliance</goalPrefix>
</configuration>
<executions>
<execution>
<id>default-descriptor</id>
<goals>
<goal>descriptor</goal>
</goals>
<phase>process-classes</phase>
</execution>
<execution>
<id>help-descriptor</id>
<goals>
<goal>helpmojo</goal>
</goals>
<phase>process-classes</phase>
</execution>
</executions>
</plugin>
</plugins>
</build>