[ERROR] Failed to execute goal org.apache.maven.plugins:maven-javadoc-plugin:3.0.1:jar (attach-javadoc) on project dubbo: MavenReportException: Error while generating Javadoc:
[ERROR] Exit code: 1 - /Users/xxx/Documents/incubator-dubbo/dubbo-common/src/main/java/org/apache/dubbo/common/logger/log4j2/Log4j2LoggerAdapter.java:23: error: package org.apache.logging.log4j does not exist
[ERROR] import org.apache.logging.log4j.LogManager;
[ERROR]                                ^
[ERROR] /Users/xxx/Documents/incubator-dubbo/dubbo-common/src/main/java/org/apache/dubbo/common/logger/log4j2/Log4j2LoggerAdapter.java:35: error: package org.apache.logging.log4j does not exist
[ERROR]     private static org.apache.logging.log4j.Level toLog4j2Level(Level level) {
[ERROR]                                            ^
[ERROR] /Users/xxx/Documents/incubator-dubbo/dubbo-common/src/main/java/org/apache/dubbo/common/logger/log4j2/Log4j2LoggerAdapter.java:57: error: package org.apache.logging.log4j does not exist
[ERROR]     private static Level fromLog4j2Level(org.apache.logging.log4j.Level level) {
[ERROR]                                                                  ^
[ERROR] /Users/xxx/Documents/incubator-dubbo/dubbo-common/src/main/java/org/apache/dubbo/common/logger/log4j2/Log4j2Logger.java:23: error: package org.apache.logging.log4j does not exist
[ERROR]     private final org.apache.logging.log4j.Logger logger;
[ERROR]                                           ^
[ERROR] /Users/xxx/Documents/incubator-dubbo/dubbo-common/src/main/java/org/apache/dubbo/common/logger/log4j2/Log4j2Logger.java:25: error: package org.apache.logging.log4j does not exist
[ERROR]     public Log4j2Logger(org.apache.logging.log4j.Logger logger) {
[ERROR]                                                 ^
[ERROR]
[ERROR] Command line was: /Library/Java/JavaVirtualMachines/jdk-11.0.1.jdk/Contents/Home/bin/javadoc @options @packages
[ERROR]
[ERROR] Refer to the generated Javadoc files in '/Users/xxx/Documents/incubator-dubbo/dubbo-all/target/apidocs' dir.
[ERROR]
[ERROR] -> [Help 1]