javadoc命令 错误: 编码 GBK 的不可映射字符 (0x80)

在Gradle工程，生成 jar 时打包报错：

> Task :javadoc FAILED
XXXX.java:105: 错误: 编码 GBK 的不可映射字符 (0x80)
FAILURE: Build failed with an exception.* What went wrong:
Execution failed for task ':javadoc'.
> Javadoc generation failed. Generated Javadoc options file (useful for troubleshooting):

很显然，这是编码问题。但是编译是成功的，而 javadoc 是失败的。

解决方法

Gradle配置 javadoc 任务，设置 编码：

 tasks.withType(Javadoc).configureEach {options.encoding = "UTF-8"options.charSet = "UTF-8"options.docEncoding = "UTF-8"}