构建这个 maven 项目曾经在很长一段时间(6 个月)内工作得很好，但今天在执行 mvn clean install 时，构建每次都开始挂起(尝试使用不同版本的 mvn，包括最新的 3.5.0 并且针对 openJDK 和 Oracle JDK - 结果是一样的)
kill -3 PID 输出
"resolver-5" #491 daemon prio=5 os_prio=0 tid=0x00007f6da8bd3800 nid=0x16b3 waiting on condition [0x00007f6d68df3000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c658c4a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"resolver-4" #490 daemon prio=5 os_prio=0 tid=0x00007f6da8bd2800 nid=0x16b2 waiting on condition [0x00007f6d69945000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c658c4a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"resolver-3" #489 daemon prio=5 os_prio=0 tid=0x00007f6da8bd9000 nid=0x16b1 waiting on condition [0x00007f6de97bc000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c658c4a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"resolver-2" #488 daemon prio=5 os_prio=0 tid=0x00007f6da8bd8800 nid=0x16b0 waiting on condition [0x00007f6de940e000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c658c4a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"resolver-1" #487 daemon prio=5 os_prio=0 tid=0x00007f6da8bd7800 nid=0x16af waiting on condition [0x00007f6de930d000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c658c4a8> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"Thread-14" #34 daemon prio=5 os_prio=0 tid=0x00007f6d9c0e7800 nid=0x73cd in Object.wait() [0x00007f6de99f7000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at org.apache.tools.ant.taskdefs.StreamPumper.waitForInput(StreamPumper.java:245)
- locked <0x00000006cbe26170> (a org.apache.tools.ant.taskdefs.StreamPumper)
at org.apache.tools.ant.taskdefs.StreamPumper.run(StreamPumper.java:125)
at java.lang.Thread.run(Thread.java:745)
"Thread-13" #33 daemon prio=5 os_prio=0 tid=0x00007f6d9c10a800 nid=0x73cb in Object.wait() [0x00007f6de9af8000]
java.lang.Thread.State: TIMED_WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at org.apache.tools.ant.taskdefs.StreamPumper.waitForInput(StreamPumper.java:245)
- locked <0x00000006cbe4a7d8> (a org.apache.tools.ant.taskdefs.StreamPumper)
at org.apache.tools.ant.taskdefs.StreamPumper.run(StreamPumper.java:125)
at java.lang.Thread.run(Thread.java:745)
"BuilderThread 3" #19 prio=5 os_prio=0 tid=0x00007f6e00927800 nid=0x7373 waiting on condition [0x00007f6dea27d000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c6284f48> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"BuilderThread 2" #18 prio=5 os_prio=0 tid=0x00007f6e00926800 nid=0x7372 in Object.wait() [0x00007f6dea49b000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
- waiting on <0x00000006cb6c4780> (a java.lang.UNIXProcess)
at java.lang.Object.wait(Object.java:502)
at java.lang.UNIXProcess.waitFor(UNIXProcess.java:395)
- locked <0x00000006cb6c4780> (a java.lang.UNIXProcess)
at org.apache.tools.ant.taskdefs.Execute.waitFor(Execute.java:534)
at org.apache.tools.ant.taskdefs.Execute.execute(Execute.java:463)
at org.apache.tools.ant.taskdefs.ExecTask.runExecute(ExecTask.java:628)
at org.apache.tools.ant.taskdefs.ExecTask.runExec(ExecTask.java:669)
at org.apache.tools.ant.taskdefs.ExecTask.execute(ExecTask.java:495)
at org.apache.tools.ant.UnknownElement.execute(UnknownElement.java:292)
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:498)
at org.apache.tools.ant.dispatch.DispatchUtils.execute(DispatchUtils.java:106)
at org.apache.tools.ant.Task.perform(Task.java:348)
at org.apache.tools.ant.Target.execute(Target.java:435)
at org.apache.tools.ant.Target.performTasks(Target.java:456)
at org.apache.tools.ant.Project.executeSortedTargets(Project.java:1393)
at org.apache.tools.ant.Project.executeTarget(Project.java:1364)
at org.apache.maven.plugin.antrun.AntRunMojo.execute(AntRunMojo.java:313)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:154)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:146)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder$1.call(MultiThreadedBuilder.java:200)
at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder$1.call(MultiThreadedBuilder.java:196)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"BuilderThread 1" #17 prio=5 os_prio=0 tid=0x00007f6e00926000 nid=0x7371 waiting on condition [0x00007f6dea39b000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c6284f48> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"process reaper" #12 daemon prio=10 os_prio=0 tid=0x00007f6db02a8800 nid=0x7369 runnable [0x00007f6dea4d5000]
java.lang.Thread.State: RUNNABLE
at java.lang.UNIXProcess.waitForProcessExit(Native Method)
at java.lang.UNIXProcess.lambda$initStreams$3(UNIXProcess.java:289)
at java.lang.UNIXProcess$$Lambda$7/747506922.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"BuilderThread 0" #10 prio=5 os_prio=0 tid=0x00007f6e008d4800 nid=0x7367 waiting on condition [0x00007f6dea803000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c6284f48> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
"Service Thread" #8 daemon prio=9 os_prio=0 tid=0x00007f6e000c2800 nid=0x7355 runnable [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C1 CompilerThread2" #7 daemon prio=9 os_prio=0 tid=0x00007f6e000b3000 nid=0x7354 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread1" #6 daemon prio=9 os_prio=0 tid=0x00007f6e000b1800 nid=0x7353 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"C2 CompilerThread0" #5 daemon prio=9 os_prio=0 tid=0x00007f6e000ae800 nid=0x7352 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Signal Dispatcher" #4 daemon prio=9 os_prio=0 tid=0x00007f6e000ac800 nid=0x7351 waiting on condition [0x0000000000000000]
java.lang.Thread.State: RUNNABLE
"Finalizer" #3 daemon prio=8 os_prio=0 tid=0x00007f6e00084000 nid=0x7350 in Object.wait() [0x00007f6df05f4000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
- locked <0x00000006c231e5c8> (a java.lang.ref.ReferenceQueue$Lock)
at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)
"Reference Handler" #2 daemon prio=10 os_prio=0 tid=0x00007f6e0007f800 nid=0x734f in Object.wait() [0x00007f6df06f5000]
java.lang.Thread.State: WAITING (on object monitor)
at java.lang.Object.wait(Native Method)
at java.lang.Object.wait(Object.java:502)
at java.lang.ref.Reference.tryHandlePending(Reference.java:191)
- locked <0x00000006c2dd4ae0> (a java.lang.ref.Reference$Lock)
at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:153)
"main" #1 prio=5 os_prio=0 tid=0x00007f6e0000a800 nid=0x7349 waiting on condition [0x00007f6e0a5e2000]
java.lang.Thread.State: WAITING (parking)
at sun.misc.Unsafe.park(Native Method)
- parking to wait for <0x00000006c6280d98> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
at java.util.concurrent.ExecutorCompletionService.take(ExecutorCompletionService.java:193)
at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder.multiThreadedProjectTaskSegmentBuild(MultiThreadedBuilder.java:140)
at org.apache.maven.lifecycle.internal.builder.multithreaded.MultiThreadedBuilder.build(MultiThreadedBuilder.java:101)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:309)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:194)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:107)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:993)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:345)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:191)
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:498)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
"VM Thread" os_prio=0 tid=0x00007f6e00077800 nid=0x734e runnable
"GC task thread#0 (ParallelGC)" os_prio=0 tid=0x00007f6e0001f800 nid=0x734a runnable
"GC task thread#1 (ParallelGC)" os_prio=0 tid=0x00007f6e00021000 nid=0x734b runnable
"GC task thread#2 (ParallelGC)" os_prio=0 tid=0x00007f6e00023000 nid=0x734c runnable
"GC task thread#3 (ParallelGC)" os_prio=0 tid=0x00007f6e00024800 nid=0x734d runnable
"VM Periodic Task Thread" os_prio=0 tid=0x00007f6e000c5000 nid=0x7356 waiting on condition
JNI global references: 280
Heap
PSYoungGen total 1161728K, used 704160K [0x000000076ab00000, 0x00000007c0000000, 0x00000007c0000000)
eden space 979968K, 53% used [0x000000076ab00000,0x000000078a929980,0x00000007a6800000)
from space 181760K, 99% used [0x00000007b4e80000,0x00000007bfffe8f0,0x00000007c0000000)
to space 208896K, 0% used [0x00000007a6800000,0x00000007a6800000,0x00000007b3400000)
ParOldGen total 1211904K, used 320544K [0x00000006c0000000, 0x0000000709f80000, 0x000000076ab00000)
object space 1211904K, 26% used [0x00000006c0000000,0x00000006d3908220,0x0000000709f80000)
Metaspace used 92817K, capacity 96210K, committed 96512K, reserved 1134592K
class space used 10910K, capacity 11975K, committed 12032K, reserved 1048576K
这是一些奇怪的死锁问题吗？ 提前致谢!
更新 实际上构建不会永远挂起(仅 20 - 25 分钟)。还是不清楚是什么原因
最佳答案
Maven 3.5.x 有一些非常可怕的错误，即:
具体发生的情况是，如果您正在构建一个包含子模块或多个项目的项目，Maven 3.5.x 在下载重复的依赖项时偶尔会锁定。 示例:让 spring-expression-4.3.5.RELEASE 成为两个或多个项目 POM 的依赖项。它由项目 1 在“.m2\repository\org\springframework\spring-expression\4.3.5.RELEASE\spring-expression-4.3.5.RELEASE.jar”下载到 Maven Repo(当然，使用 POM 和校验和文件)。当项目 2 在同一位置检查/下载相同的依赖项时，它会锁定 20 分钟，然后在日志中报告“0 B”已下载。
直到 Maven 团队在 3.5.x 版本中解决了这个问题，我们才回到 Maven 3.3.9 并且问题消失了。 (注意:在我们项目的依赖项解析中，这通常可以在同一点重现。)
关于java - maven 在项目构建期间挂起约 20 分钟(过去工作正常)，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/43792427/
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关闭。这个问题需要detailsorclarity.它目前不接受答案。想改进这个问题吗？通过editingthispost添加细节并澄清问题.关闭8年前。Improvethisquestion在首页我有:汽车:VolvoSaabMercedesAudistatic_pages_spec.rb中的测试代码:it"shouldhavetherightselect"dovisithome_pathit{shouldhave_select('cars',:options=>['volvo','saab','mercedes','audi'])}end响应是rspec./spec/request
在Rails4.0.2中，我使用s3_direct_upload和aws-sdkgems直接为s3存储桶上传文件。在开发环境中它工作正常，但在生产环境中它会抛出如下错误，ActionView::Template::Error(noimplicitconversionofnilintoString)在View中，create_cv_url,:id=>"s3_uploader",:key=>"cv_uploads/{unique_id}/${filename}",:key_starts_with=>"cv_uploads/",:callback_param=>"cv[direct_uplo
假设我有这个范围:("aaaaa".."zzzzz")如何在不事先/每次生成整个项目的情况下从范围中获取第N个项目？ 最佳答案 一种快速简便的方法:("aaaaa".."zzzzz").first(42).last#==>"aaabp"如果出于某种原因你不得不一遍又一遍地这样做，或者如果你需要避免为前N个元素构建中间数组，你可以这样写:moduleEnumerabledefskip(n)returnto_enum:skip,nunlessblock_given?each_with_indexdo|item,index|yieldit