如何创建post-site maven插件

<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.example</groupId>
    <artifactId>post-site-plugin</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>maven-plugin</packaging>

    <dependencies>
        <dependency>
            <groupId>org.apache.maven</groupId>
            <artifactId>maven-plugin-api</artifactId>
            <version>3.8.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.maven.plugin-tools</groupId>
            <artifactId>maven-plugin-annotations</artifactId>
            <version>3.6.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

package com.example;

import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.plugins.annotations.Mojo;
import org.apache.maven.plugins.annotations.Parameter;

@Mojo(name = "post-site")
public class PostSiteMojo extends AbstractMojo {

    @Parameter(property = "postSite.message", defaultValue = "Default message")
    private String message;

    public void execute() throws MojoExecutionException {
        getLog().info("Post-site plugin executed with message: " + message);
    }
}

mvn clean install

<build>
    <plugins>
        <plugin>
            <groupId>com.example</groupId>
            <artifactId>post-site-plugin</artifactId>
            <version>1.0-SNAPSHOT</version>
            <executions>
                <execution>
                    <goals>
                        <goal>post-site</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

mvn dependency:tree