mi

有没有前台的部分demo，这个算是后台的吧，。。。

··· Cause: java.lang.ExceptionInInitializerError ···

``` * What went wrong: Execution failed for task ':compileJava'. > java.lang.ExceptionInInitializerError * Try: Run with --stacktrace option to get the stack trace. Run with --info or --debug option to...

``` mz@mzdeMacBook-Pro ~ % java -version java version "1.8.0_231" Java(TM) SE Runtime Environment (build 1.8.0_231-b11) Java HotSpot(TM) 64-Bit Server VM (build 25.231-b11, mixed mode) mz@mzdeMacBook-Pro ~ % ```

``` * Exception is: org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':compileJava'. at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:96) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:65) at org.gradle.api.internal.tasks.execution.ActionEventFiringTaskExecuter.execute(ActionEventFiringTaskExecuter.java:44) at org.gradle.api.internal.tasks.execution.TimeoutTaskExecuter.execute(TimeoutTaskExecuter.java:53) at org.gradle.api.internal.tasks.execution.SnapshotAfterExecutionTaskExecuter.execute(SnapshotAfterExecutionTaskExecuter.java:38) at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51) at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:59) at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:49) at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:61) at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:101)...