Maven Javadoc - 无法生成Javadoc

Question

I have the following dependency and build in my pom file. I'm able to manually create the javadoc with a Maven command. I can also succesfully perform a build. The output doesn't mention javadoc at all. I've also tried leaving out the output directory paths. POM File Dependency section:

<dependency>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-javadoc-plugin</artifactId>
    <version>2.8</version>
</dependency>

and then the build section:

<build>
    <finalName>D</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-javadoc-plugin</artifactId>
            <version>2.8</version>
            <configuration> 
                <outputDirectory>${project.build.directory}/javadoc</outputDirectory>
                <reportOutputDirectory>${project.reporting.outputDirectory}/javadoc</reportOutputDirectory>
                <version>2.8</version>
            </configuration>
            <executions>
                <execution>
                    <id>attach-javadocs</id>
                    <goals>
                        <goal>aggregate</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

Answer 1

The Maven Javadoc plugin doesn't run by default and needs to be bound to one of the default Maven lifecycle phases.

Here's how I would write the plugin's configuration:

    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-javadoc-plugin</artifactId>
        <version>2.8</version>
        <configuration> 
            <outputDirectory>${project.build.directory}/javadoc</outputDirectory>
            <reportOutputDirectory>${project.reporting.outputDirectory}/javadoc</reportOutputDirectory>
        </configuration>
        <executions>
            <execution>
                <id>attach-javadocs</id>
                <phase>site</phase>
                <goals>
                    <goal>aggregate</goal>
                </goals>
            </execution>
        </executions>
    </plugin>

Notice how I added an extra phase element to the execution. This will bind it to the "site" goal so that javadocs are generated when you run mvn site . Check Introduction to the Build Lifecycle if you want one of the default Java build phases.

Also note that I ditched the version parameter; by default, it should use your POM's version anyway.