作业7：常用java命令（一）

一、Javac（java compiler）

1、功能：javac是一种前端编译器，负责将源代码转换为字节码。

2、例子

（1）代码

public class TestJavac {
    static class Person{
        private String name;
        private Integer age;
        public Person() {
        }

        public Person(String name, Integer age) {
            this.name = name;
            this.age = age;
        }

        public String getName() {
            return name;
        }

        public void setName(String name) {
            this.name = name;
        }

        public Integer getAge() {
            return age;
        }

        public void setAge(Integer age) {
            this.age = age;
        }
    }

    public static void main(String[] args) {
        System.out.println("Test Javac");
        Person javac = new Person("Javac", 14);
        System.out.println(javac.getName());
        System.out.println(javac.getAge());
    }
}

（2）执行javac命令

C:UsersHBKJDesktopTestJavac>javac TestJavac.java
C:UsersHBKJDesktopTestJavac>dir
    C:UsersHBKJDesktopTestJavac 的目录
    2018/07/21  12:30    <DIR>          .
    2018/07/21  12:30    <DIR>          ..
    2018/07/21  12:26               774 TestJavac$Person.class // 内部类
    2018/07/21  12:26               783 TestJavac.class
    2018/07/21  12:26               842 TestJavac.java
                   3 个文件          2,399 字节
                   2 个目录 13,931,593,728 可用字节

二、javap

1、功能：javap是Java字节码文件分解器，能够反编译javac生成的字节码；也能够查看java编译器生成的字节码，用于分解class文件。

2、例子

（1）命令：javap -p

C:UsersHBKJDesktopTestJavac>javap -p TestJavac.class
Compiled from "TestJavac.java"
public class TestJavac {
  public TestJavac();
  public static void main(java.lang.String[]);
}

（2）命令：javap -c

C:UsersHBKJDesktopTestJavac>javap -c TestJavac.class
Compiled from "TestJavac.java"
public class TestJavac {
  public TestJavac(); // 构造器
    Code:
       0: aload_0
       1: invokespecial #1                  // Method java/lang/Object."<init>":()V
       4: return

  public static void main(java.lang.String[]);
    Code:
       0: getstatic     #2                  // Field java/lang/System.out:Ljava/io/PrintStream;
       3: ldc           #3                  // String Test Javac
       5: invokevirtual #4                  // Method java/io/PrintStream.println:(Ljava/lang/String;)V
       8: new           #5                  // class TestJavac$Person
      11: dup
      12: ldc           #6                  // String Javac
      14: bipush        14
      16: invokestatic  #7                  // Method java/lang/Integer.valueOf:(I)Ljava/lang/Integer;
      19: invokespecial #8                  // Method TestJavac$Person."<init>":(Ljava/lang/String;Ljava/lang/Integer;)V
      22: astore_1
      23: getstatic     #2                  // Field java/lang/System.out:Ljava/io/PrintStream;
      26: aload_1
      27: invokevirtual #9                  // Method TestJavac$Person.getName:()Ljava/lang/String;
      30: invokevirtual #4                  // Method java/io/PrintStream.println:(Ljava/lang/String;)V
      33: getstatic     #2                  // Field java/lang/System.out:Ljava/io/PrintStream;
      36: aload_1
      37: invokevirtual #10                 // Method TestJavac$Person.getAge:()Ljava/lang/Integer;
      40: invokevirtual #11                 // Method java/io/PrintStream.println:(Ljava/lang/Object;)V
      43: return
}

三、jps（JVM Process Status Tool）

1、功能：列出正在运行的虚拟机进程，并显示虚拟机执行主类的名称和这些进程的唯一ID。

2、主要选项

选项	作用
-q	省略主类名称（java8默认参数）
-l	输出主类名称（java10默认参数）
-v	输出虚拟机进程启动时JVM参数

3、例子（Idea IDE进程）

PS C:Windowssystem32> jps
9024 Jps
9796 Launcher
9860

PS C:Windowssystem32> jps -l
9796 org.jetbrains.jps.cmdline.Launcher
9860
8540 jdk.jcmd/sun.tools.jps.Jps

PS C:Windowssystem32> jps -v
8404 Jps -Dapplication.home=E:developsoftwarejava10jdk -Xms8m -Djdk.module.main=jdk.jcmd
9796 Launcher -Xmx700m -Djava.awt.headless=true -Djdt.compiler.useSingleThread=true -Dpreload.project.path=E:/develop/project/AlgorithmsLearning -Dpreload.config.path=C:/Users/HBKJ/.IntelliJIdea2018.1/config/options -Dcompile.parallel=false -Drebuild.on.dependency.change=true -Djava.net.preferIPv4Stack=true -Dio.netty.initialSeedUniquifier=7903075717686063478 -Dfile.encoding=GBK -Duser.language=zh -Duser.country=CN -Didea.paths.selector=IntelliJIdea2018.1 -Didea.home.path=D:softwareIntelliJ IDEA 2018.1.1 -Didea.config.path=C:UsersHBKJ.IntelliJIdea2018.1config -Didea.plugins.path=C:UsersHBKJ.IntelliJIdea2018.1configplugins -Djps.log.dir=C:/Users/HBKJ/.IntelliJIdea2018.1/system/log/build-log -Djps.fallback.jdk.home=D:/software/IntelliJ IDEA 2018.1.1/jre64 -Djps.fallback.jdk.version=1.8.0_152-release -Dio.netty.noUnsafe=true -Djava.io.tmpdir=C:/Users/HBKJ/.IntelliJIdea2018.1/system/compile-server/algorithmslearning_af8be974/_temp_ -Djps.backward.ref.index.builder=true -Dkotlin.incremental.compilation=true -Dkotlin.
9860  -Xms128m -Xmx750m -XX:ReservedCodeCacheSize=240m -XX:+UseConcMarkSweepGC -XX:SoftRefLRUPolicyMSPerMB=50 -ea -Dsun.io.useCanonCaches=false -Djava.net.preferIPv4Stack=true -XX:+HeapDumpOnOutOfMemoryError -XX:-OmitStackTraceInFastThrow -javaagent:D:/software/IntelliJ IDEA 2018.1.1/bin/JetbrainsCrack-2.7-release-str.jar -Djb.vmOptionsFile=D:softwareIntelliJ IDEA 2018.1.1inidea64.exe.vmoptions -Didea.jre.check=true -Dide.native.launcher=true -Didea.paths.selector=IntelliJIdea2018.1 -XX:ErrorFile=C:UsersHBKJjava_error_in_idea_%p.log -XX:HeapDumpPath=C:UsersHBKJjava_error_in_idea.hprof

四、jstack（Stack Trace for java）

1、功能：生成JVM当前时间的线程快照（threaddump或javacore文件）。

• 线程快照：当前JVM内每一条线程正在执行的方法堆栈的集合，生成线程快照的主要目的是为了定位线程长时间停顿的原因。
• 线程长时间停顿情况：死锁、死循环、请求外部资源等

2、主要选项

选项	作用
-l	同时显示锁的附加信息

3、例子（Idea IDE进程）

PS C:UsersHBKJ> jstack 9796
2018-07-14 14:33:38
Full thread dump Java HotSpot(TM) 64-Bit Server VM (10.0.1+10 mixed mode):

Threads class SMR info:
_java_thread_list=0x000001a3b0b585f0, length=14, elements={
0x000001a3aea36000, 0x000001a3aea37000, 0x000001a3aea3d800, 0x000001a3aea3e000,
0x000001a3af2c8800, 0x000001a3af2d1000, 0x000001a3af2d4000, 0x000001a3af2d8000,
0x000001a3af2e8800, 0x000001a3af47f800, 0x000001a3af484000, 0x000001a3afb2f000,
0x000001a38ff10000, 0x000001a3b0cb0800
}

"Reference Handler" #2 daemon prio=10 os_prio=2 tid=0x000001a3aea36000 nid=0x1e44 waiting on condition  [0x0000008ea28ff000]
   java.lang.Thread.State: RUNNABLE
        at java.lang.ref.Reference.waitForReferencePendingList(java.base@10.0.1/Native Method)
        at java.lang.ref.Reference.processPendingReferences(java.base@10.0.1/Reference.java:174)
        at java.lang.ref.Reference.access$000(java.base@10.0.1/Reference.java:44)
        at java.lang.ref.Reference$ReferenceHandler.run(java.base@10.0.1/Reference.java:138)

"Finalizer" #3 daemon prio=8 os_prio=1 tid=0x000001a3aea37000 nid=0x1308 in Object.wait()  [0x0000008ea29fe000]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(java.base@10.0.1/Native Method)
        - waiting on <0x00000000d4e5e9c0> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:151)
        - waiting to re-lock in wait() <0x00000000d4e5e9c0> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:172)
        at java.lang.ref.Finalizer$FinalizerThread.run(java.base@10.0.1/Finalizer.java:216)

"Signal Dispatcher" #4 daemon prio=9 os_prio=2 tid=0x000001a3aea3d800 nid=0x196c runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Attach Listener" #5 daemon prio=5 os_prio=2 tid=0x000001a3aea3e000 nid=0x3210 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"C2 CompilerThread0" #6 daemon prio=9 os_prio=2 tid=0x000001a3af2c8800 nid=0xe08 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

"C2 CompilerThread1" #7 daemon prio=9 os_prio=2 tid=0x000001a3af2d1000 nid=0x2a94 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

"C2 CompilerThread2" #8 daemon prio=9 os_prio=2 tid=0x000001a3af2d4000 nid=0x724 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

"C1 CompilerThread3" #9 daemon prio=9 os_prio=2 tid=0x000001a3af2d8000 nid=0x20 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

"Sweeper thread" #10 daemon prio=9 os_prio=2 tid=0x000001a3af2e8800 nid=0x2810 runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Service Thread" #11 daemon prio=9 os_prio=0 tid=0x000001a3af47f800 nid=0x23a8 runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"Common-Cleaner" #12 daemon prio=8 os_prio=1 tid=0x000001a3af484000 nid=0x29b0 in Object.wait()  [0x0000008ea33ff000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
        at java.lang.Object.wait(java.base@10.0.1/Native Method)
        - waiting on <0x00000000d4e213d8> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:151)
        - waiting to re-lock in wait() <0x00000000d4e213d8> (a java.lang.ref.ReferenceQueue$Lock)
        at jdk.internal.ref.CleanerImpl.run(java.base@10.0.1/CleanerImpl.java:148)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)
        at jdk.internal.misc.InnocuousThread.run(java.base@10.0.1/InnocuousThread.java:134)

"JPS event loop" #13 prio=5 os_prio=0 tid=0x000001a3afb2f000 nid=0x1674 runnable  [0x0000008ea45fe000]
   java.lang.Thread.State: RUNNABLE
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(java.base@10.0.1/Native Method)
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(java.base@10.0.1/WindowsSelectorImpl.java:296)
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(java.base@10.0.1/WindowsSelectorImpl.java:278)
        at sun.nio.ch.WindowsSelectorImpl.doSelect(java.base@10.0.1/WindowsSelectorImpl.java:159)
        at sun.nio.ch.SelectorImpl.lockAndDoSelect(java.base@10.0.1/SelectorImpl.java:89)
        - locked <0x00000000d4e620c8> (a io.netty.channel.nio.SelectedSelectionKeySet)
        - locked <0x00000000d4e620e0> (a java.util.Collections$UnmodifiableSet)
        - locked <0x00000000d4e62048> (a sun.nio.ch.WindowsSelectorImpl)
        at sun.nio.ch.SelectorImpl.select(java.base@10.0.1/SelectorImpl.java:100)
        at io.netty.channel.nio.SelectedSelectionKeySetSelector.select(SelectedSelectionKeySetSelector.java:62)
        at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:752)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:408)
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)

"DestroyJavaVM" #15 prio=5 os_prio=0 tid=0x000001a38ff10000 nid=0x2278 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

"NettythreadDeathWatcher-2-1" #17 daemon prio=1 os_prio=-2 tid=0x000001a3b0cb0800 nid=0x2740 waiting on condition  [0x0000008ea48fe000]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
        at java.lang.Thread.sleep(java.base@10.0.1/Native Method)
        at io.netty.util.ThreadDeathWatcher$Watcher.run(ThreadDeathWatcher.java:152)
        at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:138)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)

"VM Thread" os_prio=2 tid=0x000001a3aea31800 nid=0x1de0 runnable

"GC Thread#0" os_prio=2 tid=0x000001a38ff2c000 nid=0x9c8 runnable

"GC Thread#1" os_prio=2 tid=0x000001a38ff2d800 nid=0x410 runnable

"GC Thread#2" os_prio=2 tid=0x000001a38ff30000 nid=0x28e4 runnable

"GC Thread#3" os_prio=2 tid=0x000001a38ff33800 nid=0x22a0 runnable

"GC Thread#4" os_prio=2 tid=0x000001a38ff35800 nid=0x16e4 runnable

"GC Thread#5" os_prio=2 tid=0x000001a38ff3a800 nid=0xfd8 runnable

"GC Thread#6" os_prio=2 tid=0x000001a38ff3e000 nid=0x21a0 runnable

"GC Thread#7" os_prio=2 tid=0x000001a38ff3f000 nid=0x1b88 runnable

"G1 Main Marker" os_prio=2 tid=0x000001a38ff7e800 nid=0x2cd4 runnable

"G1 Conc#0" os_prio=2 tid=0x000001a38ff81800 nid=0xe1c runnable

"G1 Conc#1" os_prio=2 tid=0x000001a38ff82800 nid=0x91c runnable

"G1 Refine#0" os_prio=2 tid=0x000001a38ffde800 nid=0x3350 runnable

"G1 Refine#1" os_prio=2 tid=0x000001a3ae8ce000 nid=0x2d74 runnable

"G1 Refine#2" os_prio=2 tid=0x000001a3ae8d0000 nid=0x59c runnable

"G1 Refine#3" os_prio=2 tid=0x000001a3ae8d0800 nid=0x2f50 runnable

"G1 Refine#4" os_prio=2 tid=0x000001a3ae8d5800 nid=0x2750 runnable

"G1 Refine#5" os_prio=2 tid=0x000001a3ae8d8800 nid=0xa18 runnable

"G1 Refine#6" os_prio=2 tid=0x000001a3ae8db000 nid=0x1c04 runnable

"G1 Refine#7" os_prio=2 tid=0x000001a3ae8ec000 nid=0x3220 runnable

"G1 Young RemSet Sampling" os_prio=2 tid=0x000001a3ae8ec800 nid=0x23cc runnable
"VM Periodic Task Thread" os_prio=2 tid=0x000001a3af485000 nid=0x1540 waiting on condition

JNI global references: 14

#################################################
# 使用-l选项将输出Locked ownable synchronizers 内容
#################################################
PS C:UsersHBKJ> jstack -l  9796
2018-07-14 14:41:41
Full thread dump Java HotSpot(TM) 64-Bit Server VM (10.0.1+10 mixed mode):

Threads class SMR info:
_java_thread_list=0x000001a3b0b585f0, length=14, elements={
0x000001a3aea36000, 0x000001a3aea37000, 0x000001a3aea3d800, 0x000001a3aea3e000,
0x000001a3af2c8800, 0x000001a3af2d1000, 0x000001a3af2d4000, 0x000001a3af2d8000,
0x000001a3af2e8800, 0x000001a3af47f800, 0x000001a3af484000, 0x000001a3afb2f000,
0x000001a38ff10000, 0x000001a3b0cb0800
}

"Reference Handler" #2 daemon prio=10 os_prio=2 tid=0x000001a3aea36000 nid=0x1e44 waiting on condition  [0x0000008ea28ff000]
   java.lang.Thread.State: RUNNABLE
        at java.lang.ref.Reference.waitForReferencePendingList(java.base@10.0.1/Native Method)
        at java.lang.ref.Reference.processPendingReferences(java.base@10.0.1/Reference.java:174)
        at java.lang.ref.Reference.access$000(java.base@10.0.1/Reference.java:44)
        at java.lang.ref.Reference$ReferenceHandler.run(java.base@10.0.1/Reference.java:138)

   Locked ownable synchronizers:
        - None

"Finalizer" #3 daemon prio=8 os_prio=1 tid=0x000001a3aea37000 nid=0x1308 in Object.wait()  [0x0000008ea29fe000]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(java.base@10.0.1/Native Method)
        - waiting on <0x00000000d4e5e9c0> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:151)
        - waiting to re-lock in wait() <0x00000000d4e5e9c0> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:172)
        at java.lang.ref.Finalizer$FinalizerThread.run(java.base@10.0.1/Finalizer.java:216)

   Locked ownable synchronizers:
        - None

"Signal Dispatcher" #4 daemon prio=9 os_prio=2 tid=0x000001a3aea3d800 nid=0x196c runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

   Locked ownable synchronizers:
        - None

"Attach Listener" #5 daemon prio=5 os_prio=2 tid=0x000001a3aea3e000 nid=0x3210 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

   Locked ownable synchronizers:
        - None

"C2 CompilerThread0" #6 daemon prio=9 os_prio=2 tid=0x000001a3af2c8800 nid=0xe08 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

   Locked ownable synchronizers:
        - None

"C2 CompilerThread1" #7 daemon prio=9 os_prio=2 tid=0x000001a3af2d1000 nid=0x2a94 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

   Locked ownable synchronizers:
        - None

"C2 CompilerThread2" #8 daemon prio=9 os_prio=2 tid=0x000001a3af2d4000 nid=0x724 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

   Locked ownable synchronizers:
        - None

"C1 CompilerThread3" #9 daemon prio=9 os_prio=2 tid=0x000001a3af2d8000 nid=0x20 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE
   No compile task

   Locked ownable synchronizers:
        - None

"Sweeper thread" #10 daemon prio=9 os_prio=2 tid=0x000001a3af2e8800 nid=0x2810 runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

   Locked ownable synchronizers:
        - None

"Service Thread" #11 daemon prio=9 os_prio=0 tid=0x000001a3af47f800 nid=0x23a8 runnable  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

   Locked ownable synchronizers:
        - None

"Common-Cleaner" #12 daemon prio=8 os_prio=1 tid=0x000001a3af484000 nid=0x29b0 in Object.wait()  [0x0000008ea33ff000]
   java.lang.Thread.State: TIMED_WAITING (on object monitor)
        at java.lang.Object.wait(java.base@10.0.1/Native Method)
        - waiting on <0x00000000d4e213d8> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(java.base@10.0.1/ReferenceQueue.java:151)
        - waiting to re-lock in wait() <0x00000000d4e213d8> (a java.lang.ref.ReferenceQueue$Lock)
        at jdk.internal.ref.CleanerImpl.run(java.base@10.0.1/CleanerImpl.java:148)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)
        at jdk.internal.misc.InnocuousThread.run(java.base@10.0.1/InnocuousThread.java:134)

   Locked ownable synchronizers:
        - None

"JPS event loop" #13 prio=5 os_prio=0 tid=0x000001a3afb2f000 nid=0x1674 runnable  [0x0000008ea45fe000]
   java.lang.Thread.State: RUNNABLE
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll0(java.base@10.0.1/Native Method)
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.poll(java.base@10.0.1/WindowsSelectorImpl.java:296)
        at sun.nio.ch.WindowsSelectorImpl$SubSelector.access$400(java.base@10.0.1/WindowsSelectorImpl.java:278)
        at sun.nio.ch.WindowsSelectorImpl.doSelect(java.base@10.0.1/WindowsSelectorImpl.java:159)
        at sun.nio.ch.SelectorImpl.lockAndDoSelect(java.base@10.0.1/SelectorImpl.java:89)
        - locked <0x00000000d4e620c8> (a io.netty.channel.nio.SelectedSelectionKeySet)
        - locked <0x00000000d4e620e0> (a java.util.Collections$UnmodifiableSet)
        - locked <0x00000000d4e62048> (a sun.nio.ch.WindowsSelectorImpl)
        at sun.nio.ch.SelectorImpl.select(java.base@10.0.1/SelectorImpl.java:100)
        at io.netty.channel.nio.SelectedSelectionKeySetSelector.select(SelectedSelectionKeySetSelector.java:62)
        at io.netty.channel.nio.NioEventLoop.select(NioEventLoop.java:752)
        at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:408)
        at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)

   Locked ownable synchronizers:
        - None

"DestroyJavaVM" #15 prio=5 os_prio=0 tid=0x000001a38ff10000 nid=0x2278 waiting on condition  [0x0000000000000000]
   java.lang.Thread.State: RUNNABLE

   Locked ownable synchronizers:
        - None

"NettythreadDeathWatcher-2-1" #17 daemon prio=1 os_prio=-2 tid=0x000001a3b0cb0800 nid=0x2740 waiting on condition  [0x0000008ea48fe000]
   java.lang.Thread.State: TIMED_WAITING (sleeping)
        at java.lang.Thread.sleep(java.base@10.0.1/Native Method)
        at io.netty.util.ThreadDeathWatcher$Watcher.run(ThreadDeathWatcher.java:152)
        at io.netty.util.concurrent.DefaultThreadFactory$DefaultRunnableDecorator.run(DefaultThreadFactory.java:138)
        at java.lang.Thread.run(java.base@10.0.1/Thread.java:844)

   Locked ownable synchronizers:
        - None
"VM Thread" os_prio=2 tid=0x000001a3aea31800 nid=0x1de0 runnable

"GC Thread#0" os_prio=2 tid=0x000001a38ff2c000 nid=0x9c8 runnable

"GC Thread#1" os_prio=2 tid=0x000001a38ff2d800 nid=0x410 runnable

"GC Thread#2" os_prio=2 tid=0x000001a38ff30000 nid=0x28e4 runnable

"GC Thread#3" os_prio=2 tid=0x000001a38ff33800 nid=0x22a0 runnable

"GC Thread#4" os_prio=2 tid=0x000001a38ff35800 nid=0x16e4 runnable

"GC Thread#5" os_prio=2 tid=0x000001a38ff3a800 nid=0xfd8 runnable

"GC Thread#6" os_prio=2 tid=0x000001a38ff3e000 nid=0x21a0 runnable

"GC Thread#7" os_prio=2 tid=0x000001a38ff3f000 nid=0x1b88 runnable

"G1 Main Marker" os_prio=2 tid=0x000001a38ff7e800 nid=0x2cd4 runnable

"G1 Conc#0" os_prio=2 tid=0x000001a38ff81800 nid=0xe1c runnable

"G1 Conc#1" os_prio=2 tid=0x000001a38ff82800 nid=0x91c runnable

"G1 Refine#0" os_prio=2 tid=0x000001a38ffde800 nid=0x3350 runnable

"G1 Refine#1" os_prio=2 tid=0x000001a3ae8ce000 nid=0x2d74 runnable

"G1 Refine#2" os_prio=2 tid=0x000001a3ae8d0000 nid=0x59c runnable

"G1 Refine#3" os_prio=2 tid=0x000001a3ae8d0800 nid=0x2f50 runnable

"G1 Refine#4" os_prio=2 tid=0x000001a3ae8d5800 nid=0x2750 runnable

"G1 Refine#5" os_prio=2 tid=0x000001a3ae8d8800 nid=0xa18 runnable

"G1 Refine#6" os_prio=2 tid=0x000001a3ae8db000 nid=0x1c04 runnable

"G1 Refine#7" os_prio=2 tid=0x000001a3ae8ec000 nid=0x3220 runnable

"G1 Young RemSet Sampling" os_prio=2 tid=0x000001a3ae8ec800 nid=0x23cc runnable
"VM Periodic Task Thread" os_prio=2 tid=0x000001a3af485000 nid=0x1540 waiting on condition

JNI global references: 14

四、在线分析工具

Java Thread Dump Analyzer

简单Java线程状态介绍