Maven站点命令失败：寻找pmd插件：我不需要它

Question

这是我的pom文件报告部分：

<reporting>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-javadoc-plugin</artifactId>
            <version>2.7</version>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-changelog-plugin</artifactId>
            <version>2.1</version>  
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>surefire-report-maven-plugin</artifactId>
            <inherited>true</inherited>
            <reportSets>
                <reportSet>
                    <reports>
                        <report>report-only</report>
                    </reports>
                </reportSet>
            </reportSets>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>cobertura-maven-plugin</artifactId>
            <version>2.4</version>
            <inherited>true</inherited>
            <configuration>
                <formats>
                    <format>html</format>
                    <format>xml</format>
                </formats>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.codehaus.mojo</groupId>
            <artifactId>findbugs-maven-plugin</artifactId>
            <version>2.1</version>
            <inherited>true</inherited>
            <configuration>
                <xmlOutput>true</xmlOutput>
                <effort>Max</effort>
                <!-- <visitors> FindDeadLocalStores,UnreadFields</visitors>-->
                <debug>true</debug>
                <relaxed>false</relaxed>
                <includeTests>true</includeTests>
                <threshold>Low</threshold>
                <findbugsXmlOutput>true</findbugsXmlOutput>
                <findbugsXmlWithMessages>true</findbugsXmlWithMessages>                 
            </configuration>
        </plugin>
    </plugins>
</reporting>

但是，当我跑

时

> mvn site

它给了我以下错误：

> [INFO]
> ------------------------------------------------------------------------ 
> [ERROR] BUILD ERROR [INFO]
> ------------------------------------------------------------------------   
> [INFO] Failed to resolve artifact.
> Failed to resolve artifact, possibly
> due to a repository list that is not appropriate 
> org.apache.maven.plugins:maven-pmd-plugin:pom:2.6-SNAPSHOT
> from the specified remote
> repositories:   central
> (http://repo1.maven.org/maven2),  
> aaa-yyy
> (http://nexus.yyy.com/nexus/content/groups/public-all)
> [INFO]
> ------------------------------------------------------------------------   
> [INFO] For more information, run Maven
> with the -e switch [INFO]
> ------------------------------------------------------------------------   
> [INFO] Total time: 1 second   
> [INFO] Finished at: Fri Mar 04 09:44:43 CST 2011  
> [INFO] Final Memory: 8M/24M
> [INFO]
> ------------------------------------------------------------------------

我不想使用maven pmd插件。我只需要以下报告找到bug，surefire，cobertura，java doc，changelog。但是，当我运行maven网站时，我得到了Java NCSS，这是我不需要的。如何排除在运行maven站点时生成的Java NCSS？