The JetBrains gradle-intellij-plugin uses the project.version as a task input. I have defined a custom class, SimpleVersion, for the version rather than a string. This class implements Serializable. The class is able to be serialized by the Gradle task input machinery. However, when the Gradle change detection machinery attempts to deserialize the class during the processResources task, I get a ClassNotFoundException. I know the class is on the buildscript classpath. Here is the stack trace:
at org.gradle.cache.internal.btree.BTreePersistentIndexedCache.get(BTreePersistentIndexedCache.java:128)
at org.gradle.cache.internal.DefaultMultiProcessSafePersistentIndexedCache$1.create(DefaultMultiProcessSafePersistentIndexedCache.java:37)
at org.gradle.cache.internal.DefaultFileLockManager$DefaultFileLock.readFile(DefaultFileLockManager.java:153)
at org.gradle.cache.internal.DefaultCacheAccess$UnitOfWorkFileAccess.readFile(DefaultCacheAccess.java:396)
at org.gradle.cache.internal.DefaultMultiProcessSafePersistentIndexedCache.get(DefaultMultiProcessSafePersistentIndexedCache.java:35)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$2.create(CacheBackedTaskHistoryRepository.java:104)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$2.create(CacheBackedTaskHistoryRepository.java:99)
at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:192)
at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:102)
at org.gradle.cache.internal.DefaultCacheFactory$ReferenceTrackingCache.useCache(DefaultCacheFactory.java:183)
at org.gradle.api.internal.changedetection.state.DefaultTaskArtifactStateCacheAccess.useCache(DefaultTaskArtifactStateCacheAccess.java:56)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository.loadHistory(CacheBackedTaskHistoryRepository.java:99)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository.getHistory(CacheBackedTaskHistoryRepository.java:45)
at org.gradle.api.internal.changedetection.changes.DefaultTaskArtifactStateRepository.getStateFor(DefaultTaskArtifactStateRepository.java:57)
at org.gradle.api.internal.changedetection.changes.ShortCircuitTaskArtifactStateRepository.getStateFor(ShortCircuitTaskArtifactStateRepository.java:47)
at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52)
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.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185)
at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
at org.gradle.execution.taskgraph.ParallelTaskPlanExecutor.process(ParallelTaskPlanExecutor.java:47)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:110)
at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
at org.gradle.initialization.DefaultGradleLauncher$4.run(DefaultGradleLauncher.java:154)
at org.gradle.internal.Factories$1.create(Factories.java:22)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:52)
at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:151)
at org.gradle.initialization.DefaultGradleLauncher.access$200(DefaultGradleLauncher.java:32)
at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:99)
at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:93)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90)
at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:62)
at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:93)
at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:82)
at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:94)
at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:43)
at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:28)
at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:81)
at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:46)
at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:51)
at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:28)
at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:43)
at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:173)
at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:241)
at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:214)
at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35)
at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24)
at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:207)
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 sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:497)
at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:55)
at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:36)
at org.gradle.launcher.GradleMain.main(GradleMain.java:23)
Caused by: java.lang.ClassNotFoundException: com.linkedin.ligradle.product.SimpleVersion
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at java.io.ObjectInputStream.resolveClass(ObjectInputStream.java:626)
at org.gradle.internal.io.ClassLoaderObjectInputStream.resolveClass(ClassLoaderObjectInputStream.java:40)
at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1613)
at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1518)
at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1774)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1351)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
at org.gradle.internal.serialize.DefaultSerializer.read(DefaultSerializer.java:45)
at org.gradle.internal.serialize.MapSerializer.read(MapSerializer.java:37)
at org.gradle.api.internal.changedetection.state.InputPropertiesSerializer.read(InputPropertiesSerializer.java:35)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$LazyTaskExecution$TaskHistorySerializer.read(CacheBackedTaskHistoryRepository.java:289)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$TaskHistorySerializer.read(CacheBackedTaskHistoryRepository.java:160)
at org.gradle.api.internal.changedetection.state.CacheBackedTaskHistoryRepository$TaskHistorySerializer.read(CacheBackedTaskHistoryRepository.java:146)
at org.gradle.cache.internal.btree.BTreePersistentIndexedCache$DataBlock.getValue(BTreePersistentIndexedCache.java:661)
at org.gradle.cache.internal.btree.BTreePersistentIndexedCache.get(BTreePersistentIndexedCache.java:120)
... 73 more
Environment is RedHat Linux 6.6, Gradle 2.13, Java 1.8u40.