content: package net.agkn.hll.serialization;
  
  /*
   * Copyright 2013 Aggregate Knowledge, Inc.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  import net.agkn.hll.HLLType;
  
  /**
   * The metadata and parameters associated with a HLL.
   */
  public interface IHLLMetadata {
      /**
       * @return the schema version of the HLL. This will never be <code>null</code>.
       */
      int schemaVersion();
  
      /**
       * @return the type of the HLL. This will never be <code>null</code>.
       */
      HLLType HLLType();
  
      /**
       * @return the log-base-2 of the register count parameter of the HLL. This
       *         will always be greater than or equal to 4 and less than or equal
       *         to 31.
       */
      int registerCountLog2();
  
      /**
       * @return the register width parameter of the HLL. This will always be
       *         greater than or equal to 1 and less than or equal to 8.
       */
      int registerWidth();
  
      /**
       * @return the log-base-2 of the explicit cutoff cardinality. This will always
       *         be greater than or equal to zero and less than 31, per the specification.
       */
      int log2ExplicitCutoff();
  
      /**
       * @return <code>true</code> if the {@link HLLType#EXPLICIT} representation
       *         has been disabled. <code>false</code> otherwise.
       */
      boolean explicitOff();
  
      /**
       * @return <code>true</code> if the {@link HLLType#EXPLICIT} representation
       *         cutoff cardinality is set to be automatically chosen,
       *         <code>false</code> otherwise.
       */
      boolean explicitAuto();
  
      /**
       * @return <code>true</code> if the {@link HLLType#SPARSE} representation
       *         is enabled.
       */
      boolean sparseEnabled();
  }