没学过gradle，想打jar包。
gradle build，报错：
FAILURE: Build failed with an exception.
- What went wrong:
Could not create service of type FileAccessTimeJournal using GradleUserHomeScopeServices.createFileAccessTimeJournal().
Unexpected lock protocol found in lock file. Expected 3, found 0.
命令行输入gradlew，报错：
Downloading https://services.gradle.org/distributions/gradle-5.2.1-all.zip
Exception in thread "main" java.io.IOException: Unable to tunnel through proxy. Proxy returns "HTTP/1.1 400 Bad Request"
gradle版本：gradle-5.2.1
