Maven (D): Write a maven plugin

• In the maven, all things are plug his own main function is dependent on plug-in implementation, but it also provides us with a wealth of plug-in library, the most important is https://maven.apache.org/plugins/ and http://www.mojohaus.org/plugins.html .
• The use of plug-ins
  • In the pom files in the project, the build tag with a tag plugins, in which you can define multiple plug-ins; the figure below, you can see this maven project in function of all plug-ins, and plug-ins

• A plug-in handwriting
  • First create a maven project
  • Pom in the value of the packaging label changed maven-plugin

    <packaging>maven-plugin</packaging>

  • The introduction of dependence

    <dependency>
        <groupId>org.apache.maven</groupId>
        <artifactId>maven-plugin-api</artifactId>
        <version>3.5.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.maven.plugin-tools</groupId>
        <artifactId>maven-plugin-annotations</artifactId>
        <version>3.5</version>
        <scope>provided</scope>
    </dependency>

  • Create a class, inheritance

    AbstractMojo.class

  • Rewrite inside the execute method

    public void execute() throws MojoExecutionException, MojoFailureException {
        System.out.println("具体业务");
    
    }

  • On a class annotated

    @Mojo

  • And specify the name and defaultPhase, the value of name is the current goal, defaultPhase this goal is the phase in which the

    @Mojo(name="lhy",defaultPhase = LifecyclePhase.PACKAGE)

  • Then you plug it finished, it is not very simple.
• Use plug-ins
  • The introduction of your plug-in project

    <build>
       <plugins>
          <plugin>
             <groupId>com.lhy</groupId>
             <artifactId>lhy-plugin</artifactId>
             <version>1.0-SNAPSHOT</version>
          </plugin>
       </plugins>
    </build>

  • Then you can see

• • Double-click he can run directly. Or mvn lhy: lhy can also run.
  • But sometimes we need to pass parameters, then we can define a property in the plug-in, and then add @Parameter comment, and then you can pass parameters when calling the

    @Parameter
    private String msg;

  • Run mvn lhy: lhy -Dmsg = ... to ok
  • So far, one of our basic plug-in is complete, from development to have a use, but all are run by command or double-click, how to let him run it automatically
  • In fact, can be configured in the pom

    <build>
       <plugins>
          <plugin>
             <groupId>com.lhy</groupId>
             <artifactId>lhy-plugin</artifactId>
             <version>1.0-SNAPSHOT</version>
             <configuration>
                <msg></msg>
             </configuration>
             <executions>
                <execution>
                   <phase>install</phase>
                   <goals>
                      <goal>lhy</goal>
                   </goals>
                </execution>
             </executions>
          </plugin>
       </plugins>
    </build>

  • configuration configuration parameters
  • configured to perform the execution phase and goal
  • Then when we execute phase plug where the goal will be executed automatically
• Common plug-ins
  • findbugs static code checking
  • unified version upgrade versions
  • Packaging source code source
  • assembly packed zip, war
  • tomcat7