Maven plugin default phase

Question

I am trying to write a Hello World Maven plugin.

I assigned defaultPhase=LifecyclePhase.CLEAN to it but when I execute mvn clean it is not working.

When I execute mvn gorov:clean it is working.

Any suggestions?

DS

The code is:

Location in project: maven-plugin\src\main\java\com\gorovdude\plugins\maven\mojos\WriteConsoleMojo.java

package com.gorovdude.plugins.maven.mojos;

import java.io.File;
import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugin.MojoFailureException;
import org.apache.maven.plugins.annotations.LifecyclePhase;
import org.apache.maven.plugins.annotations.Mojo;

@Mojo(name = "clean", defaultPhase = LifecyclePhase.CLEAN, threadSafe = true, aggregator = true)

public class WriteConsoleMojo extends AbstractMojo {

    public void execute() throws MojoExecutionException, MojoFailureException {
        try {

            String path = "C:\\Apache-maven-3.2.5\\testing.txt";
            System.out.println("testing");
            File f = new File(path);

            f.createNewFile();

        } catch (Exception e) {
            throw new MojoExecutionException(e.getMessage(), e);
        }
    }

}

The pom.xml of the plugin:

Location in maven-plugin\pom.xml

<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.gorovdude</groupId>
    <artifactId>gorov-maven-plugin</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>maven-plugin</packaging>
    <description>gorov Maven Plugin</description>

    <properties>
        <mavenVersion>3.0</mavenVersion>
        <mavenPluginVersion>3.1</mavenPluginVersion>
    </properties>

    <prerequisites>
        <maven>${mavenVersion}</maven>
    </prerequisites>

    <dependencies>
        <dependency>
            <groupId>org.apache.maven</groupId>
            <artifactId>maven-core</artifactId>
            <version>${mavenVersion}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.maven</groupId>
            <artifactId>maven-plugin-api</artifactId>
            <version>${mavenVersion}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.maven.plugin-tools</groupId>
            <artifactId>maven-plugin-annotations</artifactId>
            <version>${mavenPluginVersion}</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.maven</groupId>
            <artifactId>maven-artifact</artifactId>
            <version>2.0.9</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-plugin-plugin</artifactId>
                <version>${mavenPluginVersion}</version>
                <executions>
                    <execution>
                        <id>generate-descriptor</id>
                        <goals>
                            <goal>descriptor</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <goalPrefix>gorov</goalPrefix>
                    <skipErrorNoDescriptorsFound>true</skipErrorNoDescriptorsFound>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

The pom.xml that I run mvn commands on:

Location in Project: maven-plugin\src\test\pom.xml

<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.gorovdude</groupId>
    <artifactId>test-gorov-maven-plugin</artifactId>
    <version>0.0.1-SNAPSHOT</version>

    <description>Testing the plugin</description>

    <build>
        <plugins>
            <plugin>
                <groupId>com.gorovdude</groupId>
                <artifactId>gorov-maven-plugin</artifactId>
                <version>0.0.1-SNAPSHOT</version>
            </plugin>
        </plugins>
    </build>
</project>

'when i execute `mvn clean`' -- Where's the pom of the project where you're running `mvn clean`? — Joe, Feb 22 '15 at 06:30

score 4 · Answer 1 · answered Sep 22 '16 at 09:18

Your source code of the plugin can be called as following

<build>
    <plugins>
        <plugin>
            <groupId>com.gorovdude</groupId>
            <artifactId>gorov-maven-plugin</artifactId>
            <version>0.0.1-SNAPSHOT</version>
            <executions>
                <execution>
                    <goals>
                        <goal>clean</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

You have to specify the goal in the executions. if you type "maven clean", you just call the maven clean plugin, not yours. A plugin may contain multiple goals, unless you define in the executions of you project, which the goals you want to run, they won't run.

Look here: https://maven.apache.org/guides/plugin/guide-java-plugin-development.html

To be precise, it's `mvn clean` you have to type and the `clean` there refers to the `clean` _phase_ of the `clean` lifecycle (which has the `clean` goal of the `clean` plugin bound to it by default). — Gerold Broser, Feb 04 '18 at 16:00

Gerold Broser · Answer 2 · 2018-02-04T16:49:59.610

See the help text if you enter just mvn:

No goals have been specified for this build. You must specify a valid
lifecycle phase or a goal in the format <plugin-prefix>:<goal> [...].
Available lifecycle phases are: [...] , clean, [...].

If you enter mvn clean you're not invoking the clean goal of your plugin but the clean phase of the clean lifecycle (which has the clean goal of the [maven-]clean[-plugin] plugin bound to it by default).

If you enter mvn gorov:clean you're using the plugin prefix gorov declared in <goalPrefix>gorov</goalPrefix> in your plugin's POM (though this declaration wouldn't be necessary since the same prefix would be derived from the artifact ID of your plugin gorov-maven-plugin by default).

See also Maven: Lifecycle vs. Phase vs. Plugin vs. Goal.

Maven plugin default phase

2 Answers2