問題描述

我真的很迷茫，我不知道如何面對和解決我的問題.我有一段簡單的 Java 代碼，導致 JVM 崩潰:

I'm really lost and I don't know how to face and solve my problem. I have a piece of simple Java Code, which leads to a JVM crash:

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00000001057ce9d4, pid=10727, tid=18947
#
# JRE version: Java(TM) SE Runtime Environment (8.0_73-b02) (build 1.8.0_73-b02)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.73-b02 mixed mode bsd-amd64 compressed oops)
# Problematic frame:
# V  [libjvm.dylib+0x3ce9d4]  PhaseIdealLoop::idom_no_update(Node*) const+0x12
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.java.com/bugreport/crash.jsp
#

---------------  T H R E A D  ---------------

Current thread (0x00007feeef003800):  JavaThread "C2 CompilerThread0" daemon [_thread_in_native, id=18947, stack(0x0000700000ec4000,0x0000700000fc4000)]

siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x0000000000000008

我不知道如何解決這個問題.該程序非常簡單，它通過 Kafka 接收消息并根據收到的消息觸發任務.如果我添加兩個不同的任務，程序會在 900 - 1,500 條消息后崩潰.所有消息都是相同的，并且程序不使用任何 JNI 東西(據我所知，使用過的 3rd 方庫也不使用任何 JNI).

I have no idea on how to solve the problem. The program is pretty simple, it receives a message through Kafka and triggers tasks based on the message received. If I add two different tasks, the program crashes after 900 - 1,500 messages. All of the messages are the same and the program does not use any JNI stuff (the used 3rd party libraries don't use any JNI as well, as far as I'm informed).

我從未遇到過這個問題，但我希望/需要找到一種方法來找出問題所在.我已經使用過其他版本的 JVM(Java 8.0_66、8.0_73-b02 和 8.0_74-b02).那么我能做什么呢?非常感謝！

I never faced this problem, but I'd love/need to find a way on how to figure out what the problem is. I already used other versions of the JVM (Java 8.0_66, 8.0_73-b02, and 8.0_74-b02). So what can I do? Thank you so much!

編輯(1):有時我也會收到以下錯誤/信息:

EDIT (1): Sometimes I also get the following error/info:

...
# JRE version: Java(TM) SE Runtime Environment (8.0_73-b02) (build 1.8.0_73-b02)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.73-b02 mixed mode bsd-amd64 compressed oops)
# Problematic frame:
# V  [libjvm.dylib+0x3ce9d4]
...

編輯 (2):我將 Java 版本更新為 8.0_74.錯誤仍然存??在:(.

EDIT (2): I updated my Java version to 8.0_74. The error is still there :(.

#
# A fatal error has been detected by the Java Runtime Environment:
#
#  SIGSEGV (0xb) at pc=0x00000001073cdef8, pid=11227, tid=19715
#
# JRE version: Java(TM) SE Runtime Environment (8.0_74-b02) (build 1.8.0_74-b02)
# Java VM: Java HotSpot(TM) 64-Bit Server VM (25.74-b02 mixed mode bsd-amd64 compressed oops)
# Problematic frame:
# V  [libjvm.dylib+0x3cdef8]  PhaseIdealLoop::idom_no_update(Node*) const+0x12
#
# Failed to write core dump. Core dumps have been disabled. To enable core dumping, try "ulimit -c unlimited" before starting Java again
#
# If you would like to submit a bug report, please visit:
#   http://bugreport.java.com/bugreport/crash.jsp
#

---------------  T H R E A D  ---------------

Current thread (0x00007f89e481c800):  JavaThread "C2 CompilerThread1" daemon [_thread_in_native, id=19715, stack(0x000070000104a000,0x000070000114a000)]

siginfo: si_signo: 11 (SIGSEGV), si_code: 1 (SEGV_MAPERR), si_addr: 0x0000000000000008

編輯(3):核心轉儲

所以最后我創建了一個核心轉儲并將其加載到 Java VisualVM 中(我無法使用 DROY 提供的解決方案，因為調用 jmap 會導致另一個錯誤:附加到核心文件時出錯:無法附加到核心文件").使用 VisualVM 創建的線程轉儲結果:

So finally I created a core dump and loaded it into Java VisualVM (I could not use the solution presented by DROY because calling jmap lead to another error: "Error attaching to core file: Can't attach to the core file"). The threaddump created with VisualVM results in:

Thread 30239 "Keep-Alive-Timer": (state = BLOCKED)
    at java.lang.Thread.sleep(Native Method)
    at sun.net.www.http.KeepAliveCache.run(KeepAliveCache.java:172)
    at java.lang.Thread.run(Thread.java:745)

Thread 29699 "threadDeathWatcher-4-1": (state = BLOCKED)
    at java.lang.Thread.sleep(Native Method)
    at io.netty.util.ThreadDeathWatcher$Watcher.run(ThreadDeathWatcher.java:137)
    at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
    at java.lang.Thread.run(Thread.java:745)

Thread 26635 "nioEventLoopGroup-3-1": (state = IN_NATIVE)
    at sun.nio.ch.KQueueArrayWrapper.kevent0(Native Method)
    at sun.nio.ch.KQueueArrayWrapper.poll(KQueueArrayWrapper.java:198)
    at sun.nio.ch.KQueueSelectorImpl.doSelect(KQueueSelectorImpl.java:117)
    at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
    - locked <0x00000006c049ec98> (a io.netty.channel.nio.SelectedSelectionKeySet)
    - locked <0x00000006c049ec88> (a java.util.Collections$UnmodifiableSet)
    - locked <0x00000006c049ecb8> (a sun.nio.ch.KQueueSelectorImpl)
    at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
    at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:622)
    at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:310)
    at io.netty.util.concurrent.SingleThreadEventExecutor$2.run(SingleThreadEventExecutor.java:110)
    at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:137)
    at java.lang.Thread.run(Thread.java:745)

Thread 29187 "pool-3-thread-1": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
    at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
    at kafka.consumer.ConsumerIterator.makeNext(ConsumerIterator.scala:63)
    at kafka.consumer.ConsumerIterator.makeNext(ConsumerIterator.scala:33)
    at kafka.utils.IteratorTemplate.maybeComputeNext(IteratorTemplate.scala:66)
    at kafka.utils.IteratorTemplate.hasNext(IteratorTemplate.scala:58)
    at com.sosse.common.messaging.DefaultHandler.doRun(DefaultHandler.java:22)
    at com.sosse.common.concurrency.DefaultRunnable.run(DefaultRunnable.java:11)
    at java.util.concurrent.Executors$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)

Thread 28675 "pool-4-thread-1": (state = BLOCKED)
    at java.lang.Thread.sleep(Native Method)
    at io.netty.util.HashedWheelTimer$Worker.waitForNextTick(HashedWheelTimer.java:461)
    at io.netty.util.HashedWheelTimer$Worker.run(HashedWheelTimer.java:360)
    at java.lang.Thread.run(Thread.java:745)

Thread 28163 "ConsumerFetcherThread-analytics-group_Philipp.local-1458441725398-581eabc3-0-0": (state = IN_NATIVE)
    at sun.nio.ch.Net.poll(Native Method)
    at sun.nio.ch.SocketChannelImpl.poll(SocketChannelImpl.java:954)
    - locked <0x00000006c056d538> (a java.lang.Object)
    at sun.nio.ch.SocketAdaptor$SocketInputStream.read(SocketAdaptor.java:204)
    - locked <0x00000006c056d5b8> (a java.lang.Object)
    at sun.nio.ch.ChannelInputStream.read(ChannelInputStream.java:103)
    - locked <0x00000006c056d5f8> (a sun.nio.ch.SocketAdaptor$SocketInputStream)
    at java.nio.channels.Channels$ReadableByteChannelImpl.read(Channels.java:385)
    - locked <0x00000006c056d618> (a java.lang.Object)
    at kafka.utils.Utils$.read(Utils.scala:380)
    at kafka.network.BoundedByteBufferReceive.readFrom(BoundedByteBufferReceive.scala:54)
    at kafka.network.Receive$class.readCompletely(Transmission.scala:56)
    at kafka.network.BoundedByteBufferReceive.readCompletely(BoundedByteBufferReceive.scala:29)
    at kafka.network.BlockingChannel.receive(BlockingChannel.scala:111)
    at kafka.consumer.SimpleConsumer.liftedTree1$1(SimpleConsumer.scala:71)
    at kafka.consumer.SimpleConsumer.kafka$consumer$SimpleConsumer$$sendRequest(SimpleConsumer.scala:68)
    - locked <0x00000006c056d6e0> (a java.lang.Object)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1$$anonfun$apply$mcV$sp$1.apply$mcV$sp(SimpleConsumer.scala:112)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1$$anonfun$apply$mcV$sp$1.apply(SimpleConsumer.scala:112)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1$$anonfun$apply$mcV$sp$1.apply(SimpleConsumer.scala:112)
    at kafka.metrics.KafkaTimer.time(KafkaTimer.scala:33)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1.apply$mcV$sp(SimpleConsumer.scala:111)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1.apply(SimpleConsumer.scala:111)
    at kafka.consumer.SimpleConsumer$$anonfun$fetch$1.apply(SimpleConsumer.scala:111)
    at kafka.metrics.KafkaTimer.time(KafkaTimer.scala:33)
    at kafka.consumer.SimpleConsumer.fetch(SimpleConsumer.scala:110)
    at kafka.server.AbstractFetcherThread.processFetchRequest(AbstractFetcherThread.scala:94)
    at kafka.server.AbstractFetcherThread.doWork(AbstractFetcherThread.scala:86)
    at kafka.utils.ShutdownableThread.run(ShutdownableThread.scala:60)

Thread 27651 "analytics-group_Philipp.local-1458441725398-581eabc3-leader-finder-thread": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
    at kafka.consumer.ConsumerFetcherManager$LeaderFinderThread.doWork(ConsumerFetcherManager.scala:61)
    at kafka.utils.ShutdownableThread.run(ShutdownableThread.scala:60)

Thread 27139 "analytics-group_Philipp.local-1458441725398-581eabc3_watcher_executor": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2163)
    at kafka.consumer.ZookeeperConsumerConnector$ZKRebalancerListener$$anon$1.run(ZookeeperConsumerConnector.scala:544)

Thread 26115 "kafka-consumer-scheduler-0": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Thread 25603 "main-EventThread": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
    at java.util.concurrent.LinkedBlockingQueue.take(LinkedBlockingQueue.java:442)
    at org.apache.zookeeper.ClientCnxn$EventThread.run(ClientCnxn.java:494)

Thread 25091 "main-SendThread(localhost:2181)": (state = IN_NATIVE)
    at sun.nio.ch.KQueueArrayWrapper.kevent0(Native Method)
    at sun.nio.ch.KQueueArrayWrapper.poll(KQueueArrayWrapper.java:198)
    at sun.nio.ch.KQueueSelectorImpl.doSelect(KQueueSelectorImpl.java:117)
    at sun.nio.ch.SelectorImpl.lockAndDoSelect(SelectorImpl.java:86)
    - locked <0x00000006c0022c50> (a sun.nio.ch.Util$2)
    - locked <0x00000006c0022c60> (a java.util.Collections$UnmodifiableSet)
    - locked <0x00000006c0022c00> (a sun.nio.ch.KQueueSelectorImpl)
    at sun.nio.ch.SelectorImpl.select(SelectorImpl.java:97)
    at org.apache.zookeeper.ClientCnxnSocketNIO.doTransport(ClientCnxnSocketNIO.java:349)
    at org.apache.zookeeper.ClientCnxn$SendThread.run(ClientCnxn.java:1081)

Thread 24579 "ZkClient-EventThread-16-localhost:2181": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    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 org.I0Itec.zkclient.ZkEventThread.run(ZkEventThread.java:67)

Thread 24067 "metrics-meter-tick-thread-2": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1088)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Thread 23555 "metrics-meter-tick-thread-1": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Thread 23303 "pool-1-thread-1": (state = BLOCKED)
    at sun.misc.Unsafe.park(Native Method)
    at java.util.concurrent.locks.LockSupport.parkNanos(LockSupport.java:215)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.awaitNanos(AbstractQueuedSynchronizer.java:2078)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:1093)
    at java.util.concurrent.ScheduledThreadPoolExecutor$DelayedWorkQueue.take(ScheduledThreadPoolExecutor.java:809)
    at java.util.concurrent.ThreadPoolExecutor.getTask(ThreadPoolExecutor.java:1067)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1127)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

VM Thread 20995 "Service Thread": (state = BLOCKED)

VM Thread 20483 "C1 CompilerThread3": (state = BLOCKED)

VM Thread 19971 "C2 CompilerThread2": (state = IN_NATIVE)

VM Thread 19459 "C2 CompilerThread1": (state = IN_NATIVE)

VM Thread 18947 "C2 CompilerThread0": (state = IN_NATIVE)

Thread 15887 "Signal Dispatcher": (state = BLOCKED)

Thread 14339 "Finalizer": (state = BLOCKED)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x00000006c005fa88> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:143)
    - locked <0x00000006c005fa88> (a java.lang.ref.ReferenceQueue$Lock)
    at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:164)
    at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:209)

Thread 13827 "Reference Handler": (state = BLOCKED)
    at java.lang.Object.wait(Native Method)
    - waiting on <0x00000006c0029358> (a java.lang.ref.Reference$Lock)
    at java.lang.Object.wait(Object.java:502)
    at java.lang.ref.Reference.tryHandlePending(Reference.java:191)
    - locked <0x00000006c0029358> (a java.lang.ref.Reference$Lock)
    at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:153)

Thread 2823 "main": (state = BLOCKED)
    at java.lang.Thread.sleep(Native Method)
    at com.sosse.analytics.ActivityProducer.sleep(ActivityProducer.java:110)
    at com.sosse.analytics.DemoMain$1.startApplication(DemoMain.java:37)
    at com.sosse.common.application.DefaultApplication.start(DefaultApplication.java:166)
    - locked <0x00000006c00e6080> (a java.lang.Thread)
    at com.sosse.common.application.DefaultApplication.start(DefaultApplication.java:118)
    at com.sosse.analytics.DemoMain.main(DemoMain.java:48)

編輯(4):源代碼反序列化器

EDIT (4): Source Code Deserializer

public static Object[] deserialize(final JsonElement jsonElement, final JsonDeserializationContext context, final BiFunction<Class<?>, JsonElement, Serializable[]> timeSeriesDeserializer) {
    final JsonObject jsonObject = jsonElement.getAsJsonObject();

    // get the important classes
    final Class<?> bucketContent = resolveClass("bucketContent", jsonObject, context);

    // configuration
    final TimeUnit timeUnit = context.deserialize(jsonObject.get("timeUnit"), TimeUnit.class);
    final int bucketSize = context.deserialize(jsonObject.get("bucketSize"), int.class);
    final boolean fillNumberWithZero = context.deserialize(jsonObject.get("fillNumberWithZero"), boolean.class);

    // the values
    final Long now = context.deserialize(jsonObject.get("now"), Long.class);
    final Serializable[] timeSeries = timeSeriesDeserializer.apply(bucketContent, jsonObject.get("timeSeries"));

    @SuppressWarnings("unchecked")
    final BucketTimeSeriesConfig config = new BucketTimeSeriesConfig(bucketContent, timeUnit, timeSeries.length, bucketSize, fillNumberWithZero);
    return new Object[]{config, timeSeries, now};
}

推薦答案

崩潰報告告訴 JIT 編譯器線程發生了錯誤:

The crash report tells the error has happened in JIT compiler thread:

Current thread (0x00007f89e481c800):  JavaThread "C2 CompilerThread1"

采取以下步驟診斷編譯器問題:

Take the following steps do diagnose compiler problems:

1. 試用 JDK 9 EA 中可用的最新 JVM 構建:https://jdk9.java.網絡/下載/

如果問題消失，您可以繼續使用此版本，或者嘗試找到解決問題的確切提交，然后將其反向移植到 JDK 8.如何反向移植修復以及如何自己構建 HotSpot - 這是一個單獨的主題，但我可以告訴你是否有興趣.

If the problem disappears, you can either stay with this version or try to locate the exact commit that solves the issue and then backport it to JDK 8. How to backport fixes and how to build HotSpot yourself - it's a separate topic, but I can tell if you're interested.

如果問題仍然存在，請嘗試找到有問題的方法并將其從編譯中排除.

If the problem persists, try to find a problematic method and exclude it from compilation.

Current CompileTask: C2: 114667 5303 4 com.sosse.time.timeseries.gson.TypeConverterHelper::deserialize (157 bytes)

在您的情況下，它似乎無法編譯 TypeConverterHelper.deserialize().添加以下 JVM 選項以排除此特定方法:

Looks like in your case it fails compiling TypeConverterHelper.deserialize(). Add the following JVM option to exclude this particular method:

-XX:CompileCommand=exclude,com.sosse.time.timeseries.gson.TypeConverterHelper::deserialize

-XX:CompileCommand=exclude,com.sosse.time.timeseries.gson.*::*

-XX:-DoEscapeAnalysis
-XX:LoopUnrollLimit=0
-XX:-PartialPeelLoop
-XX:-UseLoopPredicate
-XX:-LoopUnswitching
-XX:-ReassociateInvariants
-XX:MaxInlineLevel=1
-XX:-IncrementalInline
-XX:-RangeCheckElimination
-XX:-EliminateAllocations
-XX:-UseTypeProfile
-XX:AliasLevel=0

-XX:+UnlockDiagnosticVMOptions -XX:+LogCompilation

Product/Category: HotSpot Virtual Machine (errors)
Subcategory:      J2SE Server Compiler