private void compactMemoryValidate()

in src/main/java/org/apache/datasketches/kll/KllMemoryValidate.java [115:159]
41 lines of code
14 McCabe index (conditional complexity)

  private void compactMemoryValidate(final Memory srcMem) { //FOR HEAPIFY.  NOT UPDATABLE
    if (empty && singleItem) { memoryValidateThrow(EMPTYBIT_AND_SINGLEBIT, flags); }
    final int sw = (empty ? 1 : 0) | (singleItem ? 4 : 0);

    switch (sw) {
      case 0: { //FULL_COMPACT
        if (preInts != PREAMBLE_INTS_FULL) { memoryValidateThrow(INVALID_PREINTS, preInts); }
        if (serVer != SERIAL_VERSION_EMPTY_FULL) { memoryValidateThrow(EMPTYBIT_AND_SER_VER, serVer); }
        n = getMemoryN(srcMem);
        minK = getMemoryMinK(srcMem);
        numLevels = getMemoryNumLevels(srcMem);

        // Get Levels Arr and add the last element
        levelsArr = new int[numLevels + 1];
        srcMem.getIntArray(DATA_START_ADR, levelsArr, 0, numLevels); //copies all except the last one
        final int capacityItems = KllHelper.computeTotalItemCapacity(k, m, numLevels);
        levelsArr[numLevels] = capacityItems; //load the last one

        final int retainedItems = (levelsArr[numLevels] - levelsArr[0]);
        sketchBytes = DATA_START_ADR + numLevels * Integer.BYTES + 2 * typeBytes + retainedItems * typeBytes;
        break;
      }
      case 1: { //EMPTY_COMPACT
        if (preInts != PREAMBLE_INTS_EMPTY_SINGLE) { memoryValidateThrow(EMPTYBIT_AND_PREINTS, preInts); }
        if (serVer != SERIAL_VERSION_EMPTY_FULL) { memoryValidateThrow(EMPTYBIT_AND_SER_VER, serVer); }
        n = 0;           //assumed
        minK = k;        //assumed
        numLevels = 1;   //assumed
        levelsArr = new int[] {k, k};
        sketchBytes = DATA_START_ADR_SINGLE_ITEM;
        break;
      }
      case 4: { //SINGLE_COMPACT
        if (preInts != PREAMBLE_INTS_EMPTY_SINGLE) { memoryValidateThrow(SINGLEBIT_AND_PREINTS, preInts); }
        if (serVer != SERIAL_VERSION_SINGLE) { memoryValidateThrow(SINGLEBIT_AND_SER_VER, serVer); }
        n = 1;           //assumed
        minK = k;        //assumed
        numLevels = 1;   //assumed
        levelsArr = new int[] {k - 1, k};
        sketchBytes = DATA_START_ADR_SINGLE_ITEM + typeBytes;
        break;
      }
      default: break; //can not happen
    }
  }