content: /*
   * Licensed to Elastic Search and Shay Banon under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. Elastic Search licenses this
   * file to you 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 net.csdn.common.unit;
  
  /**
   * @author kimchy (shay.banon)
   */
  public enum SizeUnit {
      SINGLE {
          @Override
          public long toSingles(long size) {
              return size;
          }
  
          @Override
          public long toKilo(long size) {
              return size / (C1 / C0);
          }
  
          @Override
          public long toMega(long size) {
              return size / (C2 / C0);
          }
  
          @Override
          public long toGiga(long size) {
              return size / (C3 / C0);
          }
      },
      KILO {
          @Override
          public long toSingles(long size) {
              return x(size, C1 / C0, MAX / (C1 / C0));
          }
  
          @Override
          public long toKilo(long size) {
              return size;
          }
  
          @Override
          public long toMega(long size) {
              return size / (C2 / C1);
          }
  
          @Override
          public long toGiga(long size) {
              return size / (C3 / C1);
          }
      },
      MEGA {
          @Override
          public long toSingles(long size) {
              return x(size, C2 / C0, MAX / (C2 / C0));
          }
  
          @Override
          public long toKilo(long size) {
              return x(size, C2 / C1, MAX / (C2 / C1));
          }
  
          @Override
          public long toMega(long size) {
              return size;
          }
  
          @Override
          public long toGiga(long size) {
              return size / (C3 / C2);
          }
      },
      GIGA {
          @Override
          public long toSingles(long size) {
              return x(size, C3 / C0, MAX / (C3 / C0));
          }
  
          @Override
          public long toKilo(long size) {
              return x(size, C3 / C1, MAX / (C3 / C1));
          }
  
          @Override
          public long toMega(long size) {
              return x(size, C3 / C2, MAX / (C3 / C2));
          }
  
          @Override
          public long toGiga(long size) {
              return size;
          }
      };
  
      static final long C0 = 1L;
      static final long C1 = C0 * 1000L;
      static final long C2 = C1 * 1000L;
      static final long C3 = C2 * 1000L;
  
      static final long MAX = Long.MAX_VALUE;
  
      /**
       * Scale d by m, checking for overflow.
       * This has a short name to make above code more readable.
       */
      static long x(long d, long m, long over) {
          if (d > over) return Long.MAX_VALUE;
          if (d < -over) return Long.MIN_VALUE;
          return d * m;
      }
  
  
      public long toSingles(long size) {
          throw new AbstractMethodError();
      }
  
      public long toKilo(long size) {
          throw new AbstractMethodError();
      }
  
      public long toMega(long size) {
          throw new AbstractMethodError();
      }
  
      public long toGiga(long size) {
          throw new AbstractMethodError();
      }
  }