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@Override
public @Nullable V getIfPresent(Object key, boolean recordStats) {
  Node<K, V> node = data.get(nodeFactory.newLookupKey(key));
  if (node == null) {
    if (recordStats) {
      statsCounter().recordMisses(1);
    }
    if (drainStatusOpaque() == REQUIRED) {
      scheduleDrainBuffers();
    }
    return null;
  }

  V value = node.getValue();
  long now = expirationTicker().read();
  if (hasExpired(node, now) || (collectValues() && (value == null))) {
    if (recordStats) {
      statsCounter().recordMisses(1);
    }
    scheduleDrainBuffers();
    return null;
  }

  if ((value != null) && !isComputingAsync(value)) {
    @SuppressWarnings("unchecked")
    var castedKey = (K) key;
    setAccessTime(node, now);
    tryExpireAfterRead(node, castedKey, value, expiry(), now);
  }
  V refreshed = afterRead(node, now, recordStats);
  return (refreshed == null) ? value : refreshed;

这是一个get方法，先看get方法干了什么。

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@SuppressWarnings({"MultiVariableDeclaration",
    "OvershadowingSubclassFields", "PMD.OneDeclarationPerLine"})
abstract class MpscChunkedArrayQueue<E> extends MpscChunkedArrayQueueColdProducerFields<E> {
  byte p000, p001, p002, p003, p004, p005, p006, p007;
  byte p008, p009, p010, p011, p012, p013, p014, p015;
  byte p016, p017, p018, p019, p020, p021, p022, p023;
  byte p024, p025, p026, p027, p028, p029, p030, p031;
  byte p032, p033, p034, p035, p036, p037, p038, p039;
  byte p040, p041, p042, p043, p044, p045, p046, p047;
  byte p048, p049, p050, p051, p052, p053, p054, p055;
  byte p056, p057, p058, p059, p060, p061, p062, p063;
  byte p064, p065, p066, p067, p068, p069, p070, p071;
  byte p072, p073, p074, p075, p076, p077, p078, p079;
  byte p080, p081, p082, p083, p084, p085, p086, p087;
  byte p088, p089, p090, p091, p092, p093, p094, p095;
  byte p096, p097, p098, p099, p100, p101, p102, p103;
  byte p104, p105, p106, p107, p108, p109, p110, p111;
  byte p112, p113, p114, p115, p116, p117, p118, p119;

  MpscChunkedArrayQueue(int initialCapacity, int maxCapacity) {
    super(initialCapacity, maxCapacity);
  }
  前面这堆无意义的字符，是用来隔离冷热数据的垫片，为什么是120Byte  是因为一般来说对象头有12B，数据刚好落在第三行，如果想要刚好凑到第二行，因为情况可能会有变化，甚至cpu的缓存是120Bye，那这时候垫片就垫不到了。