private void findTop()

in modules/accumulo/src/main/java/org/apache/fluo/accumulo/iterators/SnapshotIterator.java [82:188]
95 lines of code
27 McCabe index (conditional complexity)

  private void findTop() throws IOException {
    outer: while (source.hasTop() && readLockKey == null) {
      long invalidationTime = -1;
      long dataPointer = -1;

      if (source.getTopKey().getColumnFamilyData().equals(NOTIFY_CF_BS)) {
        throw new IllegalStateException("seeing notifications during snapshot iteration");
      }

      curCol.set(source.getTopKey());

      while (source.hasTop()
          && curCol.equals(source.getTopKey(), PartialKey.ROW_COLFAM_COLQUAL_COLVIS)) {
        ColumnType colType = ColumnType.from(source.getTopKey());
        long ts = source.getTopKey().getTimestamp() & ColumnConstants.TIMESTAMP_MASK;

        switch (colType) {
          case TX_DONE: {
            source.skipToPrefix(curCol, ColumnType.WRITE);
            continue;
          }
          case WRITE: {
            long timePtr = WriteValue.getTimestamp(source.getTopValue().get());

            if (timePtr > invalidationTime) {
              invalidationTime = timePtr;
            }

            if (dataPointer == -1) {
              if (ts <= snaptime) {
                dataPointer = timePtr;
                source.skipToPrefix(curCol, ColumnType.DEL_LOCK);
                continue;
              } else {
                source.skipToTimestamp(curCol, ColumnType.WRITE.encode(snaptime));
                continue;
              }
            }
            break;
          }
          case DEL_LOCK: {
            if (ts > invalidationTime) {
              invalidationTime = ts;
            }
            if (returnReadLockPresent) {
              source.skipToPrefix(curCol, ColumnType.RLOCK);
            } else {
              source.skipToPrefix(curCol, ColumnType.LOCK);
            }
            continue;
          }
          case RLOCK: {
            if (returnReadLockPresent) {
              rememberReadLock(source.getTopKey(), source.getTopValue());
            }

            source.skipToPrefix(curCol, ColumnType.LOCK);
            continue;
          }
          case LOCK: {
            if (ts > invalidationTime && ts <= snaptime) {
              // nothing supersedes this lock, therefore the column is locked
              return;
            } else {
              if (dataPointer == -1) {
                source.skipColumn(curCol);
                continue outer;
              } else {
                source.skipToTimestamp(curCol, ColumnType.DATA.encode(dataPointer));
                continue;
              }
            }
          }
          case DATA: {
            if (dataPointer == ts) {
              // found data for this column
              return;
            }

            if (ts < dataPointer || dataPointer == -1) {
              source.skipColumn(curCol);
              continue outer;
            }

            if (ts > dataPointer) {
              source.skipToTimestamp(curCol, ColumnType.DATA.encode(dataPointer));
              continue;
            }
            break;
          }
          case ACK: {
            if (dataPointer == -1) {
              source.skipColumn(curCol);
              continue outer;
            } else {
              source.skipToTimestamp(curCol, ColumnType.DATA.encode(dataPointer));
              continue;
            }
          }
          default:
            throw new IllegalArgumentException();
        }
        // TODO handle case where dataPointer >=0, but no data was found
        source.next();
      }
    }
  }