code: /**
   * Copyright (c) 2004-2005, Regents of the University of California
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * Redistributions of source code must retain the above copyright notice,
   * this list of conditions and the following disclaimer.
   *
   * Redistributions in binary form must reproduce the above copyright
   * notice, this list of conditions and the following disclaimer in the
   * documentation and/or other materials provided with the distribution.
   *
   * Neither the name of the University of California, Los Angeles nor the
   * names of its contributors may be used to endorse or promote products
   * derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  package cck.stat;
  
  import cck.text.Printer;
  
  import java.util.LinkedList;
  
  /**
   * This class represents the proportion of different items with respect to one another. For example, the
   * proportion of cars, trucks, vans, etc on the highway.
   *
   * @author Ben L. Titzer
   */
  public class Proportion implements DataItem {
  
      protected final String name;
      protected LinkedList<Counter> shares;
      protected int total;
  
      /**
       * Public constructor that takes a string name.
       */
      public Proportion(String newname) {
          name = newname;
          shares = new LinkedList<Counter>();
      }
  
      public String getName() {
          return name;
      }
  
      /**
       * Generate a text report of the shares.
       * @param printer
       */
      public void print(Printer printer) {
          printer.print("\n " + name);
          printer.print("\n---------------------------------------------------------------------");
  
          for (Counter s : shares) {
              // TODO: print out the fraction
              s.print(printer);
          }
  
          printer.print("\n");
      }
  
      /**
       * LegacyRegister a counter object with this proportion.
       */
      public Counter newCounter(String name) {
          Counter s = new Counter(name);
          shares.add(s);
          return s;
      }
  
      /**
       * Register an integer count with this proportion object and return a Counter object.
       */
      public void addCounter(Counter c) {
          shares.add(c);
      }
  
      /**
       * Search for the counter with the specified string name and return it if it is registered.
       */
      public Counter getCounter(String name) {
          for (Counter s : shares) {
              if (name.equals(s.getName())) return s;
          }
  
          return null;
      }
  
      /**
       * Search for the counter with the specified name and report its proportion. Return -1 if not found.
       */
      public float getFraction(String name) {
          process(); // make sure proportions up to date
  
          Counter c = getCounter(name);
          return c == null ? -1 : c.getTotal() / (float)total;
      }
  
      /**
       * Do the computations and compute the proportions of each share.
       */
      public void process() {
          total = 0;
  
          for (Counter c : shares) {
              total += c.getTotal();
          }
      }
  
      /**
       * Return true if this proportion has any information available.
       */
      public boolean empty() {
          return (shares.isEmpty());
      }
  }
  