public class java.util.concurrent.Exchanger<V>
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: java.util.concurrent.Exchanger
  super_class: java.lang.Object
{
  private static final int ASHIFT;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 7

  private static final int MMASK;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 255

  private static final int SEQ;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 256

  private static final int NCPU;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  static final int FULL;
    descriptor: I
    flags: (0x0018) ACC_STATIC, ACC_FINAL

  private static final int SPINS;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 1024

  private static final java.lang.Object NULL_ITEM;
    descriptor: Ljava/lang/Object;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final java.lang.Object TIMED_OUT;
    descriptor: Ljava/lang/Object;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private final java.util.concurrent.Exchanger$Participant participant;
    descriptor: Ljava/util/concurrent/Exchanger$Participant;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private volatile java.util.concurrent.Exchanger$Node[] arena;
    descriptor: [Ljava/util/concurrent/Exchanger$Node;
    flags: (0x0042) ACC_PRIVATE, ACC_VOLATILE

  private volatile java.util.concurrent.Exchanger$Node slot;
    descriptor: Ljava/util/concurrent/Exchanger$Node;
    flags: (0x0042) ACC_PRIVATE, ACC_VOLATILE

  private volatile int bound;
    descriptor: I
    flags: (0x0042) ACC_PRIVATE, ACC_VOLATILE

  private static final sun.misc.Unsafe U;
    descriptor: Lsun/misc/Unsafe;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final long BOUND;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final long SLOT;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final long MATCH;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final long BLOCKER;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final int ABASE;
    descriptor: I
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=3, locals=5, args_size=0
         0: .line 278
            invokestatic java.lang.Runtime.getRuntime:()Ljava/lang/Runtime;
            invokevirtual java.lang.Runtime.availableProcessors:()I
            putstatic java.util.concurrent.Exchanger.NCPU:I
         1: .line 285
            getstatic java.util.concurrent.Exchanger.NCPU:I
            sipush 510
            if_icmplt 2
            sipush 255
            goto 3
      StackMap locals:
      StackMap stack:
         2: getstatic java.util.concurrent.Exchanger.NCPU:I
            iconst_1
            iushr
      StackMap locals:
      StackMap stack: int
         3: putstatic java.util.concurrent.Exchanger.FULL:I
         4: .line 299
            new java.lang.Object
            dup
            invokespecial java.lang.Object.<init>:()V
            putstatic java.util.concurrent.Exchanger.NULL_ITEM:Ljava/lang/Object;
         5: .line 306
            new java.lang.Object
            dup
            invokespecial java.lang.Object.<init>:()V
            putstatic java.util.concurrent.Exchanger.TIMED_OUT:Ljava/lang/Object;
         6: .line 640
            invokestatic sun.misc.Unsafe.getUnsafe:()Lsun/misc/Unsafe;
            putstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
         7: .line 641
            ldc Ljava/util/concurrent/Exchanger;
            astore 1 /* ek */
        start local 1 // java.lang.Class ek
         8: .line 642
            ldc Ljava/util/concurrent/Exchanger$Node;
            astore 2 /* nk */
        start local 2 // java.lang.Class nk
         9: .line 643
            ldc [Ljava/util/concurrent/Exchanger$Node;
            astore 3 /* ak */
        start local 3 // java.lang.Class ak
        10: .line 644
            ldc Ljava/lang/Thread;
            astore 4 /* tk */
        start local 4 // java.lang.Class tk
        11: .line 645
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
        12: .line 646
            aload 1 /* ek */
            ldc "bound"
            invokevirtual java.lang.Class.getDeclaredField:(Ljava/lang/String;)Ljava/lang/reflect/Field;
        13: .line 645
            invokevirtual sun.misc.Unsafe.objectFieldOffset:(Ljava/lang/reflect/Field;)J
            putstatic java.util.concurrent.Exchanger.BOUND:J
        14: .line 647
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
        15: .line 648
            aload 1 /* ek */
            ldc "slot"
            invokevirtual java.lang.Class.getDeclaredField:(Ljava/lang/String;)Ljava/lang/reflect/Field;
        16: .line 647
            invokevirtual sun.misc.Unsafe.objectFieldOffset:(Ljava/lang/reflect/Field;)J
            putstatic java.util.concurrent.Exchanger.SLOT:J
        17: .line 649
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
        18: .line 650
            aload 2 /* nk */
            ldc "match"
            invokevirtual java.lang.Class.getDeclaredField:(Ljava/lang/String;)Ljava/lang/reflect/Field;
        19: .line 649
            invokevirtual sun.misc.Unsafe.objectFieldOffset:(Ljava/lang/reflect/Field;)J
            putstatic java.util.concurrent.Exchanger.MATCH:J
        20: .line 651
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
        21: .line 652
            aload 4 /* tk */
            ldc "parkBlocker"
            invokevirtual java.lang.Class.getDeclaredField:(Ljava/lang/String;)Ljava/lang/reflect/Field;
        22: .line 651
            invokevirtual sun.misc.Unsafe.objectFieldOffset:(Ljava/lang/reflect/Field;)J
            putstatic java.util.concurrent.Exchanger.BLOCKER:J
        23: .line 653
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 3 /* ak */
            invokevirtual sun.misc.Unsafe.arrayIndexScale:(Ljava/lang/Class;)I
            istore 0 /* s */
        start local 0 // int s
        24: .line 655
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 3 /* ak */
            invokevirtual sun.misc.Unsafe.arrayBaseOffset:(Ljava/lang/Class;)I
            sipush 128
            iadd
            putstatic java.util.concurrent.Exchanger.ABASE:I
        end local 4 // java.lang.Class tk
        end local 3 // java.lang.Class ak
        end local 2 // java.lang.Class nk
        end local 1 // java.lang.Class ek
        25: .line 657
            goto 28
        end local 0 // int s
      StackMap locals:
      StackMap stack: java.lang.Exception
        26: astore 1 /* e */
        start local 1 // java.lang.Exception e
        27: .line 658
            new java.lang.Error
            dup
            aload 1 /* e */
            invokespecial java.lang.Error.<init>:(Ljava/lang/Throwable;)V
            athrow
        end local 1 // java.lang.Exception e
        start local 0 // int s
        28: .line 660
      StackMap locals: int
      StackMap stack:
            iload 0 /* s */
            iload 0 /* s */
            iconst_1
            isub
            iand
            ifne 29
            iload 0 /* s */
            sipush 128
            if_icmple 30
        29: .line 661
      StackMap locals:
      StackMap stack:
            new java.lang.Error
            dup
            ldc "Unsupported array scale"
            invokespecial java.lang.Error.<init>:(Ljava/lang/String;)V
            athrow
        end local 0 // int s
        30: .line 662
      StackMap locals:
      StackMap stack:
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature
           24   26     0     s  I
           28   30     0     s  I
            8   25     1    ek  Ljava/lang/Class<*>;
            9   25     2    nk  Ljava/lang/Class<*>;
           10   25     3    ak  Ljava/lang/Class<*>;
           11   25     4    tk  Ljava/lang/Class<*>;
           27   28     1     e  Ljava/lang/Exception;
      Exception table:
        from    to  target  type
           6    25      26  Class java.lang.Exception

  private final java.lang.Object arenaExchange(java.lang.Object, boolean, long);
    descriptor: (Ljava/lang/Object;ZJ)Ljava/lang/Object;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Code:
      stack=7, locals=20, args_size=4
        start local 0 // java.util.concurrent.Exchanger this
        start local 1 // java.lang.Object item
        start local 2 // boolean timed
        start local 3 // long ns
         0: .line 362
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
            astore 5 /* a */
        start local 5 // java.util.concurrent.Exchanger$Node[] a
         1: .line 363
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.participant:Ljava/util/concurrent/Exchanger$Participant;
            invokevirtual java.util.concurrent.Exchanger$Participant.get:()Ljava/lang/Object;
            checkcast java.util.concurrent.Exchanger$Node
            astore 6 /* p */
        start local 6 // java.util.concurrent.Exchanger$Node p
         2: .line 364
            aload 6 /* p */
            getfield java.util.concurrent.Exchanger$Node.index:I
            istore 7 /* i */
        start local 7 // int i
         3: .line 366
      StackMap locals: java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            iload 7 /* i */
            bipush 7
            ishl
            getstatic java.util.concurrent.Exchanger.ABASE:I
            iadd
            i2l
            dup2
            lstore 11 /* j */
        start local 11 // long j
         4: invokevirtual sun.misc.Unsafe.getObjectVolatile:(Ljava/lang/Object;J)Ljava/lang/Object;
            checkcast java.util.concurrent.Exchanger$Node
            astore 13 /* q */
        start local 13 // java.util.concurrent.Exchanger$Node q
         5: .line 367
            aload 13 /* q */
            ifnull 12
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            aload 13 /* q */
            aconst_null
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 12
         6: .line 368
            aload 13 /* q */
            getfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
            astore 14 /* v */
        start local 14 // java.lang.Object v
         7: .line 369
            aload 13 /* q */
            aload 1 /* item */
            putfield java.util.concurrent.Exchanger$Node.match:Ljava/lang/Object;
         8: .line 370
            aload 13 /* q */
            getfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
            astore 15 /* w */
        start local 15 // java.lang.Thread w
         9: .line 371
            aload 15 /* w */
            ifnull 11
        10: .line 372
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 15 /* w */
            invokevirtual sun.misc.Unsafe.unpark:(Ljava/lang/Object;)V
        11: .line 373
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int top top top long java.util.concurrent.Exchanger$Node java.lang.Object java.lang.Thread
      StackMap stack:
            aload 14 /* v */
            areturn
        end local 15 // java.lang.Thread w
        end local 14 // java.lang.Object v
        12: .line 375
      StackMap locals:
      StackMap stack:
            iload 7 /* i */
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.bound:I
            dup
            istore 8 /* b */
        start local 8 // int b
        13: sipush 255
            iand
            dup
            istore 9 /* m */
        start local 9 // int m
        14: if_icmpgt 62
            aload 13 /* q */
            ifnonnull 62
        15: .line 376
            aload 6 /* p */
            aload 1 /* item */
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        16: .line 377
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            aconst_null
            aload 6 /* p */
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 60
        17: .line 378
            iload 2 /* timed */
            ifeq 18
            iload 9 /* m */
            ifne 18
            invokestatic java.lang.System.nanoTime:()J
            lload 3 /* ns */
            ladd
            goto 19
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int int int top long java.util.concurrent.Exchanger$Node
      StackMap stack:
        18: lconst_0
      StackMap locals:
      StackMap stack: long
        19: lstore 14 /* end */
        start local 14 // long end
        20: .line 379
            invokestatic java.lang.Thread.currentThread:()Ljava/lang/Thread;
            astore 16 /* t */
        start local 16 // java.lang.Thread t
        21: .line 380
            aload 6 /* p */
            getfield java.util.concurrent.Exchanger$Node.hash:I
            istore 17 /* h */
        start local 17 // int h
        22: sipush 1024
            istore 18 /* spins */
        start local 18 // int spins
        23: .line 381
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int int int top long java.util.concurrent.Exchanger$Node long java.lang.Thread int int
      StackMap stack:
            aload 6 /* p */
            getfield java.util.concurrent.Exchanger$Node.match:Ljava/lang/Object;
            astore 19 /* v */
        start local 19 // java.lang.Object v
        24: .line 382
            aload 19 /* v */
            ifnull 29
        25: .line 383
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 6 /* p */
            getstatic java.util.concurrent.Exchanger.MATCH:J
            aconst_null
            invokevirtual sun.misc.Unsafe.putOrderedObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        26: .line 384
            aload 6 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        27: .line 385
            aload 6 /* p */
            iload 17 /* h */
            putfield java.util.concurrent.Exchanger$Node.hash:I
        28: .line 386
            aload 19 /* v */
            areturn
        29: .line 388
      StackMap locals: java.lang.Object
      StackMap stack:
            iload 18 /* spins */
            ifle 37
        30: .line 389
            iload 17 /* h */
            iload 17 /* h */
            iconst_1
            ishl
            ixor
            istore 17 /* h */
            iload 17 /* h */
            iload 17 /* h */
            iconst_3
            iushr
            ixor
            istore 17 /* h */
            iload 17 /* h */
            iload 17 /* h */
            bipush 10
            ishl
            ixor
            istore 17 /* h */
        31: .line 390
            iload 17 /* h */
            ifne 33
        32: .line 391
            sipush 1024
            aload 16 /* t */
            invokevirtual java.lang.Thread.getId:()J
            l2i
            ior
            istore 17 /* h */
            goto 23
        33: .line 392
      StackMap locals:
      StackMap stack:
            iload 17 /* h */
            ifge 23
        34: .line 393
            iinc 18 /* spins */ -1
            iload 18 /* spins */
            sipush 511
            iand
            ifne 23
        35: .line 394
            invokestatic java.lang.Thread.yield:()V
        36: .line 395
            goto 23
        37: .line 396
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            invokevirtual sun.misc.Unsafe.getObjectVolatile:(Ljava/lang/Object;J)Ljava/lang/Object;
            aload 6 /* p */
            if_acmpeq 39
        38: .line 397
            sipush 1024
            istore 18 /* spins */
            goto 23
        39: .line 398
      StackMap locals:
      StackMap stack:
            aload 16 /* t */
            invokevirtual java.lang.Thread.isInterrupted:()Z
            ifne 49
            iload 9 /* m */
            ifne 49
        40: .line 399
            iload 2 /* timed */
            ifeq 42
        41: .line 400
            lload 14 /* end */
            invokestatic java.lang.System.nanoTime:()J
            lsub
            dup2
            lstore 3 /* ns */
            lconst_0
            lcmp
            ifle 49
        42: .line 401
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 16 /* t */
            getstatic java.util.concurrent.Exchanger.BLOCKER:J
            aload 0 /* this */
            invokevirtual sun.misc.Unsafe.putObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        43: .line 402
            aload 6 /* p */
            aload 16 /* t */
            putfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
        44: .line 403
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            invokevirtual sun.misc.Unsafe.getObjectVolatile:(Ljava/lang/Object;J)Ljava/lang/Object;
            aload 6 /* p */
            if_acmpne 46
        45: .line 404
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            iconst_0
            lload 3 /* ns */
            invokevirtual sun.misc.Unsafe.park:(ZJ)V
        46: .line 405
      StackMap locals:
      StackMap stack:
            aload 6 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
        47: .line 406
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 16 /* t */
            getstatic java.util.concurrent.Exchanger.BLOCKER:J
            aconst_null
            invokevirtual sun.misc.Unsafe.putObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        48: .line 407
            goto 23
        49: .line 408
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            invokevirtual sun.misc.Unsafe.getObjectVolatile:(Ljava/lang/Object;J)Ljava/lang/Object;
            aload 6 /* p */
            if_acmpne 23
        50: .line 409
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* a */
            lload 11 /* j */
            aload 6 /* p */
            aconst_null
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 23
        51: .line 410
            iload 9 /* m */
            ifeq 53
        52: .line 411
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.BOUND:J
            iload 8 /* b */
            iload 8 /* b */
            sipush 256
            iadd
            iconst_1
            isub
            invokevirtual sun.misc.Unsafe.compareAndSwapInt:(Ljava/lang/Object;JII)Z
            pop
        53: .line 412
      StackMap locals:
      StackMap stack:
            aload 6 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        54: .line 413
            aload 6 /* p */
            iload 17 /* h */
            putfield java.util.concurrent.Exchanger$Node.hash:I
        55: .line 414
            aload 6 /* p */
            dup
            getfield java.util.concurrent.Exchanger$Node.index:I
            iconst_1
            iushr
            dup_x1
            putfield java.util.concurrent.Exchanger$Node.index:I
            istore 7 /* i */
        56: .line 415
            invokestatic java.lang.Thread.interrupted:()Z
            ifeq 58
        57: .line 416
            aconst_null
            areturn
        58: .line 417
      StackMap locals:
      StackMap stack:
            iload 2 /* timed */
            ifeq 3
            iload 9 /* m */
            ifne 3
            lload 3 /* ns */
            lconst_0
            lcmp
            ifgt 3
        59: .line 418
            getstatic java.util.concurrent.Exchanger.TIMED_OUT:Ljava/lang/Object;
            areturn
        end local 19 // java.lang.Object v
        end local 18 // int spins
        end local 17 // int h
        end local 16 // java.lang.Thread t
        end local 14 // long end
        60: .line 424
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int int int top long java.util.concurrent.Exchanger$Node
      StackMap stack:
            aload 6 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        61: .line 425
            goto 3
        62: .line 427
      StackMap locals:
      StackMap stack:
            aload 6 /* p */
            getfield java.util.concurrent.Exchanger$Node.bound:I
            iload 8 /* b */
            if_icmpeq 70
        63: .line 428
            aload 6 /* p */
            iload 8 /* b */
            putfield java.util.concurrent.Exchanger$Node.bound:I
        64: .line 429
            aload 6 /* p */
            iconst_0
            putfield java.util.concurrent.Exchanger$Node.collides:I
        65: .line 430
            iload 7 /* i */
            iload 9 /* m */
            if_icmpne 66
            iload 9 /* m */
            ifne 67
      StackMap locals:
      StackMap stack:
        66: iload 9 /* m */
            goto 68
      StackMap locals:
      StackMap stack:
        67: iload 9 /* m */
            iconst_1
            isub
      StackMap locals:
      StackMap stack: int
        68: istore 7 /* i */
        69: .line 431
            goto 79
        70: .line 432
      StackMap locals:
      StackMap stack:
            aload 6 /* p */
            getfield java.util.concurrent.Exchanger$Node.collides:I
            dup
            istore 10 /* c */
        start local 10 // int c
        71: iload 9 /* m */
            if_icmplt 73
            iload 9 /* m */
            getstatic java.util.concurrent.Exchanger.FULL:I
            if_icmpeq 73
        72: .line 433
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.BOUND:J
            iload 8 /* b */
            iload 8 /* b */
            sipush 256
            iadd
            iconst_1
            iadd
            invokevirtual sun.misc.Unsafe.compareAndSwapInt:(Ljava/lang/Object;JII)Z
            ifne 78
        73: .line 434
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int int int int long java.util.concurrent.Exchanger$Node
      StackMap stack:
            aload 6 /* p */
            iload 10 /* c */
            iconst_1
            iadd
            putfield java.util.concurrent.Exchanger$Node.collides:I
        74: .line 435
            iload 7 /* i */
            ifne 75
            iload 9 /* m */
            goto 76
      StackMap locals:
      StackMap stack:
        75: iload 7 /* i */
            iconst_1
            isub
      StackMap locals:
      StackMap stack: int
        76: istore 7 /* i */
        77: .line 436
            goto 79
        78: .line 438
      StackMap locals:
      StackMap stack:
            iload 9 /* m */
            iconst_1
            iadd
            istore 7 /* i */
        end local 10 // int c
        79: .line 439
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object int long java.util.concurrent.Exchanger$Node[] java.util.concurrent.Exchanger$Node int int int top long java.util.concurrent.Exchanger$Node
      StackMap stack:
            aload 6 /* p */
            iload 7 /* i */
            putfield java.util.concurrent.Exchanger$Node.index:I
        end local 13 // java.util.concurrent.Exchanger$Node q
        end local 11 // long j
        end local 9 // int m
        end local 8 // int b
        80: .line 364
            goto 3
        end local 7 // int i
        end local 6 // java.util.concurrent.Exchanger$Node p
        end local 5 // java.util.concurrent.Exchanger$Node[] a
        end local 3 // long ns
        end local 2 // boolean timed
        end local 1 // java.lang.Object item
        end local 0 // java.util.concurrent.Exchanger this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0   81     0   this  Ljava/util/concurrent/Exchanger<TV;>;
            0   81     1   item  Ljava/lang/Object;
            0   81     2  timed  Z
            0   81     3     ns  J
            1   81     5      a  [Ljava/util/concurrent/Exchanger$Node;
            2   81     6      p  Ljava/util/concurrent/Exchanger$Node;
            3   81     7      i  I
           13   80     8      b  I
           14   80     9      m  I
           71   79    10      c  I
            4   80    11      j  J
            5   80    13      q  Ljava/util/concurrent/Exchanger$Node;
            7   12    14      v  Ljava/lang/Object;
            9   12    15      w  Ljava/lang/Thread;
           20   60    14    end  J
           21   60    16      t  Ljava/lang/Thread;
           22   60    17      h  I
           23   60    18  spins  I
           24   60    19      v  Ljava/lang/Object;
    MethodParameters:
       Name  Flags
      item   
      timed  
      ns     

  private final java.lang.Object slotExchange(java.lang.Object, boolean, long);
    descriptor: (Ljava/lang/Object;ZJ)Ljava/lang/Object;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Code:
      stack=6, locals=12, args_size=4
        start local 0 // java.util.concurrent.Exchanger this
        start local 1 // java.lang.Object item
        start local 2 // boolean timed
        start local 3 // long ns
         0: .line 455
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.participant:Ljava/util/concurrent/Exchanger$Participant;
            invokevirtual java.util.concurrent.Exchanger$Participant.get:()Ljava/lang/Object;
            checkcast java.util.concurrent.Exchanger$Node
            astore 5 /* p */
        start local 5 // java.util.concurrent.Exchanger$Node p
         1: .line 456
            invokestatic java.lang.Thread.currentThread:()Ljava/lang/Thread;
            astore 6 /* t */
        start local 6 // java.lang.Thread t
         2: .line 457
            aload 6 /* t */
            invokevirtual java.lang.Thread.isInterrupted:()Z
            ifeq 4
         3: .line 458
            aconst_null
            areturn
         4: .line 461
      StackMap locals: java.util.concurrent.Exchanger$Node java.lang.Thread
      StackMap stack:
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.slot:Ljava/util/concurrent/Exchanger$Node;
            dup
            astore 7 /* q */
        start local 7 // java.util.concurrent.Exchanger$Node q
         5: ifnull 17
         6: .line 462
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.SLOT:J
            aload 7 /* q */
            aconst_null
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 13
         7: .line 463
            aload 7 /* q */
            getfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
            astore 8 /* v */
        start local 8 // java.lang.Object v
         8: .line 464
            aload 7 /* q */
            aload 1 /* item */
            putfield java.util.concurrent.Exchanger$Node.match:Ljava/lang/Object;
         9: .line 465
            aload 7 /* q */
            getfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
            astore 9 /* w */
        start local 9 // java.lang.Thread w
        10: .line 466
            aload 9 /* w */
            ifnull 12
        11: .line 467
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 9 /* w */
            invokevirtual sun.misc.Unsafe.unpark:(Ljava/lang/Object;)V
        12: .line 468
      StackMap locals: java.util.concurrent.Exchanger$Node java.lang.Object java.lang.Thread
      StackMap stack:
            aload 8 /* v */
            areturn
        end local 9 // java.lang.Thread w
        end local 8 // java.lang.Object v
        13: .line 471
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.NCPU:I
            iconst_1
            if_icmple 4
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.bound:I
            ifne 4
        14: .line 472
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.BOUND:J
            iconst_0
            sipush 256
            invokevirtual sun.misc.Unsafe.compareAndSwapInt:(Ljava/lang/Object;JII)Z
            ifeq 4
        15: .line 473
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.FULL:I
            iconst_2
            iadd
            bipush 7
            ishl
            anewarray java.util.concurrent.Exchanger$Node
            putfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
        16: .line 474
            goto 4
        17: .line 475
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
            ifnull 19
        18: .line 476
            aconst_null
            areturn
        19: .line 478
      StackMap locals:
      StackMap stack:
            aload 5 /* p */
            aload 1 /* item */
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        20: .line 479
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.SLOT:J
            aconst_null
            aload 5 /* p */
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 22
        21: .line 480
            goto 24
        22: .line 481
      StackMap locals:
      StackMap stack:
            aload 5 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        end local 7 // java.util.concurrent.Exchanger$Node q
        23: .line 460
            goto 4
        24: .line 486
      StackMap locals:
      StackMap stack:
            aload 5 /* p */
            getfield java.util.concurrent.Exchanger$Node.hash:I
            istore 7 /* h */
        start local 7 // int h
        25: .line 487
            iload 2 /* timed */
            ifeq 26
            invokestatic java.lang.System.nanoTime:()J
            lload 3 /* ns */
            ladd
            goto 27
      StackMap locals: int
      StackMap stack:
        26: lconst_0
      StackMap locals:
      StackMap stack: long
        27: lstore 8 /* end */
        start local 8 // long end
        28: .line 488
            getstatic java.util.concurrent.Exchanger.NCPU:I
            iconst_1
            if_icmple 29
            sipush 1024
            goto 30
      StackMap locals: long
      StackMap stack:
        29: iconst_1
      StackMap locals:
      StackMap stack: int
        30: istore 10 /* spins */
        start local 10 // int spins
        31: .line 490
            goto 55
        start local 11 // java.lang.Object v
        32: .line 491
      StackMap locals: int java.lang.Object
      StackMap stack:
            iload 10 /* spins */
            ifle 39
        33: .line 492
            iload 7 /* h */
            iload 7 /* h */
            iconst_1
            ishl
            ixor
            istore 7 /* h */
            iload 7 /* h */
            iload 7 /* h */
            iconst_3
            iushr
            ixor
            istore 7 /* h */
            iload 7 /* h */
            iload 7 /* h */
            bipush 10
            ishl
            ixor
            istore 7 /* h */
        34: .line 493
            iload 7 /* h */
            ifne 36
        35: .line 494
            sipush 1024
            aload 6 /* t */
            invokevirtual java.lang.Thread.getId:()J
            l2i
            ior
            istore 7 /* h */
            goto 55
        36: .line 495
      StackMap locals:
      StackMap stack:
            iload 7 /* h */
            ifge 55
            iinc 10 /* spins */ -1
            iload 10 /* spins */
            sipush 511
            iand
            ifne 55
        37: .line 496
            invokestatic java.lang.Thread.yield:()V
        38: .line 497
            goto 55
        39: .line 498
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.slot:Ljava/util/concurrent/Exchanger$Node;
            aload 5 /* p */
            if_acmpeq 41
        40: .line 499
            sipush 1024
            istore 10 /* spins */
            goto 55
        41: .line 500
      StackMap locals:
      StackMap stack:
            aload 6 /* t */
            invokevirtual java.lang.Thread.isInterrupted:()Z
            ifne 50
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
            ifnonnull 50
        42: .line 501
            iload 2 /* timed */
            ifeq 43
            lload 8 /* end */
            invokestatic java.lang.System.nanoTime:()J
            lsub
            dup2
            lstore 3 /* ns */
            lconst_0
            lcmp
            ifle 50
        43: .line 502
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 6 /* t */
            getstatic java.util.concurrent.Exchanger.BLOCKER:J
            aload 0 /* this */
            invokevirtual sun.misc.Unsafe.putObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        44: .line 503
            aload 5 /* p */
            aload 6 /* t */
            putfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
        45: .line 504
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.slot:Ljava/util/concurrent/Exchanger$Node;
            aload 5 /* p */
            if_acmpne 47
        46: .line 505
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            iconst_0
            lload 3 /* ns */
            invokevirtual sun.misc.Unsafe.park:(ZJ)V
        47: .line 506
      StackMap locals:
      StackMap stack:
            aload 5 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.parked:Ljava/lang/Thread;
        48: .line 507
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 6 /* t */
            getstatic java.util.concurrent.Exchanger.BLOCKER:J
            aconst_null
            invokevirtual sun.misc.Unsafe.putObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        49: .line 508
            goto 55
        50: .line 509
      StackMap locals:
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 0 /* this */
            getstatic java.util.concurrent.Exchanger.SLOT:J
            aload 5 /* p */
            aconst_null
            invokevirtual sun.misc.Unsafe.compareAndSwapObject:(Ljava/lang/Object;JLjava/lang/Object;Ljava/lang/Object;)Z
            ifeq 55
        51: .line 510
            iload 2 /* timed */
            ifeq 52
            lload 3 /* ns */
            lconst_0
            lcmp
            ifgt 52
            aload 6 /* t */
            invokevirtual java.lang.Thread.isInterrupted:()Z
            ifne 52
            getstatic java.util.concurrent.Exchanger.TIMED_OUT:Ljava/lang/Object;
            goto 53
      StackMap locals:
      StackMap stack:
        52: aconst_null
      StackMap locals:
      StackMap stack: java.lang.Object
        53: astore 11 /* v */
        54: .line 511
            goto 57
        end local 11 // java.lang.Object v
        55: .line 490
      StackMap locals:
      StackMap stack:
            aload 5 /* p */
            getfield java.util.concurrent.Exchanger$Node.match:Ljava/lang/Object;
            dup
            astore 11 /* v */
        start local 11 // java.lang.Object v
        56: ifnull 32
        57: .line 514
      StackMap locals: java.lang.Object
      StackMap stack:
            getstatic java.util.concurrent.Exchanger.U:Lsun/misc/Unsafe;
            aload 5 /* p */
            getstatic java.util.concurrent.Exchanger.MATCH:J
            aconst_null
            invokevirtual sun.misc.Unsafe.putOrderedObject:(Ljava/lang/Object;JLjava/lang/Object;)V
        58: .line 515
            aload 5 /* p */
            aconst_null
            putfield java.util.concurrent.Exchanger$Node.item:Ljava/lang/Object;
        59: .line 516
            aload 5 /* p */
            iload 7 /* h */
            putfield java.util.concurrent.Exchanger$Node.hash:I
        60: .line 517
            aload 11 /* v */
            areturn
        end local 11 // java.lang.Object v
        end local 10 // int spins
        end local 8 // long end
        end local 7 // int h
        end local 6 // java.lang.Thread t
        end local 5 // java.util.concurrent.Exchanger$Node p
        end local 3 // long ns
        end local 2 // boolean timed
        end local 1 // java.lang.Object item
        end local 0 // java.util.concurrent.Exchanger this
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0   61     0   this  Ljava/util/concurrent/Exchanger<TV;>;
            0   61     1   item  Ljava/lang/Object;
            0   61     2  timed  Z
            0   61     3     ns  J
            1   61     5      p  Ljava/util/concurrent/Exchanger$Node;
            2   61     6      t  Ljava/lang/Thread;
            5   23     7      q  Ljava/util/concurrent/Exchanger$Node;
            8   13     8      v  Ljava/lang/Object;
           10   13     9      w  Ljava/lang/Thread;
           25   61     7      h  I
           28   61     8    end  J
           31   61    10  spins  I
           32   55    11      v  Ljava/lang/Object;
           56   61    11      v  Ljava/lang/Object;
    MethodParameters:
       Name  Flags
      item   
      timed  
      ns     

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // java.util.concurrent.Exchanger this
         0: .line 523
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 524
            aload 0 /* this */
            new java.util.concurrent.Exchanger$Participant
            dup
            invokespecial java.util.concurrent.Exchanger$Participant.<init>:()V
            putfield java.util.concurrent.Exchanger.participant:Ljava/util/concurrent/Exchanger$Participant;
         2: .line 525
            return
        end local 0 // java.util.concurrent.Exchanger this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Ljava/util/concurrent/Exchanger<TV;>;

  public V exchange();
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=4, args_size=2
        start local 0 // java.util.concurrent.Exchanger this
        start local 1 // java.lang.Object x
         0: .line 563
            aload 1 /* x */
            ifnonnull 1
            getstatic java.util.concurrent.Exchanger.NULL_ITEM:Ljava/lang/Object;
            goto 2
      StackMap locals:
      StackMap stack:
         1: aload 1 /* x */
      StackMap locals:
      StackMap stack: java.lang.Object
         2: astore 3 /* item */
        start local 3 // java.lang.Object item
         3: .line 564
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
            ifnonnull 6
         4: .line 565
            aload 0 /* this */
            aload 3 /* item */
            iconst_0
            lconst_0
            invokevirtual java.util.concurrent.Exchanger.slotExchange:(Ljava/lang/Object;ZJ)Ljava/lang/Object;
            dup
            astore 2 /* v */
        start local 2 // java.lang.Object v
         5: ifnonnull 10
        end local 2 // java.lang.Object v
         6: .line 566
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object top java.lang.Object
      StackMap stack:
            invokestatic java.lang.Thread.interrupted:()Z
            ifne 9
         7: .line 567
            aload 0 /* this */
            aload 3 /* item */
            iconst_0
            lconst_0
            invokevirtual java.util.concurrent.Exchanger.arenaExchange:(Ljava/lang/Object;ZJ)Ljava/lang/Object;
            dup
            astore 2 /* v */
        start local 2 // java.lang.Object v
         8: ifnonnull 10
        end local 2 // java.lang.Object v
         9: .line 568
      StackMap locals:
      StackMap stack:
            new java.lang.InterruptedException
            dup
            invokespecial java.lang.InterruptedException.<init>:()V
            athrow
        start local 2 // java.lang.Object v
        10: .line 569
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object java.lang.Object java.lang.Object
      StackMap stack:
            aload 2 /* v */
            getstatic java.util.concurrent.Exchanger.NULL_ITEM:Ljava/lang/Object;
            if_acmpne 11
            aconst_null
            goto 12
      StackMap locals:
      StackMap stack:
        11: aload 2 /* v */
      StackMap locals:
      StackMap stack: java.lang.Object
        12: areturn
        end local 3 // java.lang.Object item
        end local 2 // java.lang.Object v
        end local 1 // java.lang.Object x
        end local 0 // java.util.concurrent.Exchanger this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0   13     0  this  Ljava/util/concurrent/Exchanger<TV;>;
            0   13     1     x  TV;
            5    6     2     v  Ljava/lang/Object;
            8    9     2     v  Ljava/lang/Object;
           10   13     2     v  Ljava/lang/Object;
            3   13     3  item  Ljava/lang/Object;
    Exceptions:
      throws java.lang.InterruptedException
    Signature: (TV;)TV;
    MethodParameters:
      Name  Flags
      x     

  public V exchange(V, long, java.util.concurrent.TimeUnit);
    descriptor: (Ljava/lang/Object;JLjava/util/concurrent/TimeUnit;)Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=9, args_size=4
        start local 0 // java.util.concurrent.Exchanger this
        start local 1 // java.lang.Object x
        start local 2 // long timeout
        start local 4 // java.util.concurrent.TimeUnit unit
         0: .line 618
            aload 1 /* x */
            ifnonnull 1
            getstatic java.util.concurrent.Exchanger.NULL_ITEM:Ljava/lang/Object;
            goto 2
      StackMap locals:
      StackMap stack:
         1: aload 1 /* x */
      StackMap locals:
      StackMap stack: java.lang.Object
         2: astore 6 /* item */
        start local 6 // java.lang.Object item
         3: .line 619
            aload 4 /* unit */
            lload 2 /* timeout */
            invokevirtual java.util.concurrent.TimeUnit.toNanos:(J)J
            lstore 7 /* ns */
        start local 7 // long ns
         4: .line 620
            aload 0 /* this */
            getfield java.util.concurrent.Exchanger.arena:[Ljava/util/concurrent/Exchanger$Node;
            ifnonnull 7
         5: .line 621
            aload 0 /* this */
            aload 6 /* item */
            iconst_1
            lload 7 /* ns */
            invokevirtual java.util.concurrent.Exchanger.slotExchange:(Ljava/lang/Object;ZJ)Ljava/lang/Object;
            dup
            astore 5 /* v */
        start local 5 // java.lang.Object v
         6: ifnonnull 11
        end local 5 // java.lang.Object v
         7: .line 622
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object long java.util.concurrent.TimeUnit top java.lang.Object long
      StackMap stack:
            invokestatic java.lang.Thread.interrupted:()Z
            ifne 10
         8: .line 623
            aload 0 /* this */
            aload 6 /* item */
            iconst_1
            lload 7 /* ns */
            invokevirtual java.util.concurrent.Exchanger.arenaExchange:(Ljava/lang/Object;ZJ)Ljava/lang/Object;
            dup
            astore 5 /* v */
        start local 5 // java.lang.Object v
         9: ifnonnull 11
        end local 5 // java.lang.Object v
        10: .line 624
      StackMap locals:
      StackMap stack:
            new java.lang.InterruptedException
            dup
            invokespecial java.lang.InterruptedException.<init>:()V
            athrow
        start local 5 // java.lang.Object v
        11: .line 625
      StackMap locals: java.util.concurrent.Exchanger java.lang.Object long java.util.concurrent.TimeUnit java.lang.Object java.lang.Object long
      StackMap stack:
            aload 5 /* v */
            getstatic java.util.concurrent.Exchanger.TIMED_OUT:Ljava/lang/Object;
            if_acmpne 13
        12: .line 626
            new java.util.concurrent.TimeoutException
            dup
            invokespecial java.util.concurrent.TimeoutException.<init>:()V
            athrow
        13: .line 627
      StackMap locals:
      StackMap stack:
            aload 5 /* v */
            getstatic java.util.concurrent.Exchanger.NULL_ITEM:Ljava/lang/Object;
            if_acmpne 14
            aconst_null
            goto 15
      StackMap locals:
      StackMap stack:
        14: aload 5 /* v */
      StackMap locals:
      StackMap stack: java.lang.Object
        15: areturn
        end local 7 // long ns
        end local 6 // java.lang.Object item
        end local 5 // java.lang.Object v
        end local 4 // java.util.concurrent.TimeUnit unit
        end local 2 // long timeout
        end local 1 // java.lang.Object x
        end local 0 // java.util.concurrent.Exchanger this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0   16     0     this  Ljava/util/concurrent/Exchanger<TV;>;
            0   16     1        x  TV;
            0   16     2  timeout  J
            0   16     4     unit  Ljava/util/concurrent/TimeUnit;
            6    7     5        v  Ljava/lang/Object;
            9   10     5        v  Ljava/lang/Object;
           11   16     5        v  Ljava/lang/Object;
            3   16     6     item  Ljava/lang/Object;
            4   16     7       ns  J
    Exceptions:
      throws java.lang.InterruptedException, java.util.concurrent.TimeoutException
    Signature: (TV;JLjava/util/concurrent/TimeUnit;)TV;
    MethodParameters:
         Name  Flags
      x        
      timeout  
      unit     
}
Signature: <V:Ljava/lang/Object;>Ljava/lang/Object;
SourceFile: "Exchanger.java"
NestMembers:
  java.util.concurrent.Exchanger$Node  java.util.concurrent.Exchanger$Participant
InnerClasses:
  final Node = java.util.concurrent.Exchanger$Node of java.util.concurrent.Exchanger
  final Participant = java.util.concurrent.Exchanger$Participant of java.util.concurrent.Exchanger