public void addCache(GemFireVM systemEntity, EntrySnapshot snap) {
    if (!snap.getName().equals(name)) {
      throw new IllegalArgumentException(
          "All snapshots in a compound snapshot must have the same name");
    }
    // individuals.put(systemEntity, snap);

    Object value = snap.getValue();
    if (value != null) {
      allValues.add(value.toString());
    } else {
      allValues.add("null");
    }
    Object userAttribute = snap.getUserAttribute();
    if (userAttribute != null) {
      allUserAttributes.add(userAttribute.toString());
    } else {
      allUserAttributes.add("null");
    }

    long modified = snap.getLastModifiedTime();
    if (modified > 0 && modified > lastModifiedTime) {
      lastModifiedTime = modified;
    }

    long access = snap.getLastAccessTime();
    if (access > 0 && access > lastAccessTime) {
      lastAccessTime = access;
    }

    long hitCount = snap.getNumberOfHits();
    if (hitCount > 0) {
      numHits += hitCount;
    }

    long missCount = snap.getNumberOfMisses();
    if (missCount > 0) {
      numMisses += missCount;
    }

    float hitRatio = snap.getHitRatio();
    if (hitRatio >= 0.00) {
      hitResponders++;
      hitRatioSum += hitRatio;
      this.hitRatio = (float) (hitRatioSum / hitResponders);
    }

  }
Amalgamates an <code>EntrySnapshot</code> into this <code>CompoundEntrySnapshot</code>.

@param systemEntity The member of the distributed system that sent the snapshot
@param snap The snapshot to be amalgamated

@throws IllegalArgumentException If <code>snap</code> is for a region entry other than the one
        amalgamated by this snapshot.
geode-core/src/main/java/org/apache/geode/internal/admin/CompoundEntrySnapshot.java