guava/src/com/google/common/collect/MapMakerInternalMap.java
@VisibleForTesting
  E copyEntry(E original, E newNext) {
    int hash = original.getHash();
    return segmentFor(hash).copyEntry(original, newNext);
  }
@VisibleForTesting
  E copyEntry(E original, E newNext) {
    int hash = original.getHash();
    return segmentFor(hash).copyEntry(original, newNext);
  }
Guarded By Segment.this