为什么使用新的 Gradle 版本（2.3）构建失败？

Question

我们有用于构建多个项目的 Gradle 脚本。它在 gradle 2.2.1 版本中运行良好，但在新的 Gradle 版本 2.3 项目中没有构建。它给出了以下错误。

org.gradle.api.tasks.TaskValidationException: A problem was found with the configuration of task ':TESTGradle:startScripts'.
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:42)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
        at org.gradle.api.internal.AbstractTask.executeWithoutThrowingTaskFailure(AbstractTask.java:306)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.executeTask(AbstractTaskPlanExecutor.java:79)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:63)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:51)
        at org.gradle.execution.taskgraph.ParallelTaskPlanExecutor.process(ParallelTaskPlanExecutor.java:45)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:88)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:29)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
        at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
        at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:68)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:55)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:149)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:106)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:86)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:80)
        at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:33)
        at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:24)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:36)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
        at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:51)
        at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:169)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:237)
        at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:210)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35)
        at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:206)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:169)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33)
        at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22)
        at org.gradle.launcher.Main.doAction(Main.java:33)
        at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45)
        at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:54)
        at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:35)
        at org.gradle.launcher.GradleMain.main(GradleMain.java:23)
Caused by: org.gradle.api.InvalidUserDataException: No value has been specified for property 'mainClassName'.
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:47)
        ... 40 more

您能否提供一些建议来解决此问题？

Answer 1

2.2.1 版本的 gradle 也失败了。请参阅下面的输出：

[opal@opal-mac-2]/tmp % cat build.gradle
apply plugin: 'application'
[opal@opal-mac-2]/tmp % gradle -v

------------------------------------------------------------
Gradle 2.2.1
------------------------------------------------------------

Build time:   2014-11-24 09:45:35 UTC
Build number: none
Revision:     6fcb59c06f43a4e6b1bcb401f7686a8601a1fb4a

Groovy:       2.3.6
Ant:          Apache Ant(TM) version 1.9.3 compiled on December 23 2013
JVM:          1.8.0_05 (Oracle Corporation 25.5-b02)
OS:           Mac OS X 10.10.1 x86_64

[opal@opal-mac-2]/tmp % gradle startScripts
:compileJava UP-TO-DATE
:processResources UP-TO-DATE
:classes UP-TO-DATE
:jar UP-TO-DATE
:startScripts FAILED

FAILURE: Build failed with an exception.

* What went wrong:
A problem was found with the configuration of task ':startScripts'.
> No value has been specified for property 'mainClassName'.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Total time: 2.909 secs
[opal@opal-mac-2]/tmp % gvm use gradle 2.3

Using gradle version 2.3 in this shell.
[opal@opal-mac-2]/tmp % gradle -v

------------------------------------------------------------
Gradle 2.3
------------------------------------------------------------

Build time:   2015-02-16 05:09:33 UTC
Build number: none
Revision:     586be72bf6e3df1ee7676d1f2a3afd9157341274

Groovy:       2.3.9
Ant:          Apache Ant(TM) version 1.9.3 compiled on December 23 2013
JVM:          1.8.0_05 (Oracle Corporation 25.5-b02)
OS:           Mac OS X 10.10.1 x86_64

[opal@opal-mac-2]/tmp % gradle startScripts
:compileJava UP-TO-DATE
:processResources UP-TO-DATE
:classes UP-TO-DATE
:jar
:startScripts FAILED

FAILURE: Build failed with an exception.

* What went wrong:
A problem was found with the configuration of task ':startScripts'.
> No value has been specified for property 'mainClassName'.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

BUILD FAILED

Total time: 3.168 secs

您的构建脚本中没有指定mainClassName。