HuffmanCompressionContext.java

/*
 * This file is part of Waarp Project (named also Waarp or GG).
 *
 *  Copyright (c) 2019, Waarp SAS, and individual contributors by the @author
 *  tags. See the COPYRIGHT.txt in the distribution for a full listing of
 * individual contributors.
 *
 *  All Waarp Project is free software: you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or (at your
 * option) any later version.
 *
 * Waarp is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
 * A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along with
 * Waarp . If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * 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.
 */
package org.waarp.compress.zstdsafe;

class HuffmanCompressionContext {
  private final HuffmanTableWriterWorkspace tableWriterWorkspace =
      new HuffmanTableWriterWorkspace();
  private final HuffmanCompressionTableWorkspace compressionTableWorkspace =
      new HuffmanCompressionTableWorkspace();

  private HuffmanCompressionTable previousTable =
      new HuffmanCompressionTable(Huffman.MAX_SYMBOL_COUNT);
  private HuffmanCompressionTable temporaryTable =
      new HuffmanCompressionTable(Huffman.MAX_SYMBOL_COUNT);

  private HuffmanCompressionTable previousCandidate = previousTable;
  private HuffmanCompressionTable temporaryCandidate = temporaryTable;

  public HuffmanCompressionTable getPreviousTable() {
    return previousTable;
  }

  public HuffmanCompressionTable borrowTemporaryTable() {
    previousCandidate = temporaryTable;
    temporaryCandidate = previousTable;

    return temporaryTable;
  }

  public void discardTemporaryTable() {
    previousCandidate = previousTable;
    temporaryCandidate = temporaryTable;
  }

  public void saveChanges() {
    temporaryTable = temporaryCandidate;
    previousTable = previousCandidate;
  }

  public HuffmanCompressionTableWorkspace getCompressionTableWorkspace() {
    return compressionTableWorkspace;
  }

  public HuffmanTableWriterWorkspace getTableWriterWorkspace() {
    return tableWriterWorkspace;
  }
}