修复 Plugin execution not covered by lifecycle configuration: org.codehaus.mojo:build-helper-maven-plugin:1.8:add-source (execution: add-source, phase: generate-sources)

在maven项目中使用add-source时，pom.xml报如下错误：

Plugin execution not covered by lifecycle configuration: org.codehaus.mojo:build-helper-maven-plugin:1.8:add-source (execution: add-source, phase: generate-sources)

加入的代码如下：

            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>build-helper-maven-plugin</artifactId>
                <version>1.8</version>
                <executions>
                    <execution>
                        <id>add-source</id>
                        <phase>generate-sources</phase>
                        <goals>
                            <goal>add-source</goal>
                        </goals>
                        <configuration>
                            <sources>
                                <source>${basedir}/src/main/entity</source>
                                <source>${basedir}/src/main/modules</source>
                            </sources>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

原因是eclipse的m2e插件还没支持到execution，解决办法如下

在pom.xml文件中，<plugins></plugins>后加入如下代码：

<pluginManagement>
    <plugins>
        <!--This plugin's configuration is used to store Eclipse m2e settings only. It has no influence on the Maven build itself.-->
        <plugin>
            <groupId>org.eclipse.m2e</groupId>
            <artifactId>lifecycle-mapping</artifactId>
            <version>1.0.0</version>
            <configuration>
                <lifecycleMappingMetadata>
                    <pluginExecutions>
                        <pluginExecution>
                            <pluginExecutionFilter>
                                <groupId>
                                    org.codehaus.mojo
                                </groupId>
                                <artifactId>
                                    build-helper-maven-plugin
                                </artifactId>
                                <versionRange>
                                    [1.8,)
                                </versionRange>
                                <goals>
                                    <goal>add-source</goal>
                                </goals>
                            </pluginExecutionFilter>
                            <action>
                                <ignore></ignore>
                            </action>
                        </pluginExecution>
                    </pluginExecutions>
                </lifecycleMappingMetadata>
            </configuration>
        </plugin>
    </plugins>
</pluginManagement>

然后maven -> Update Project 即可