/*
    * Copyright 2008 FatWire Corporation. All Rights Reserved.
    *
    * 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 tools.gsf.facade.sql;
  
  import COM.FutureTense.Interfaces.IList;
  
  import java.util.Iterator;
  
  /**
   * Wrapper for an IList that turns an <tt>IList</tt> into a <tt>Iterable</tt>.
   * <p>
   * Sample usage:
   * <pre>
   * SortedSet&lt;VirtualWebroot&gt; result = new TreeSet&lt;VirtualWebroot&gt;(new UrlInfoComparator());
   * for (Row listRow : new IListIterable(ics.GetList(&quot;pr-out&quot;))) {
   *     result.add(getVirtualWebroot(listRow.getLong(&quot;id&quot;)));
   * }
   * </pre>
   *
   * @author Dolf Dijkstra
   */
  public class IListIterable implements Iterable<Row> {
      private final IList list;
  
      private final int numRows;
  
      public IListIterable(final IList list) {
          super();
          this.list = list;
          if (list != null) {
              numRows = list.numRows();
          } else {
              numRows = 0;
          }
      }
  
      public Iterator<Row> iterator() {
          if (list == null || !list.hasData()) {
              return new Iterator<Row>() {
  
                  public boolean hasNext() {
                      return false;
                  }
  
                  public Row next() {
                      return null;
                  }
  
                  public void remove() {
                      throw new RuntimeException("Can not remove");
                  }
  
              };
          }
          return new Iterator<Row>() {
              private int rowNum = 0;
  
              public boolean hasNext() {
                  return rowNum < numRows;
              }
  
              public Row next() {
                  rowNum++;
                  list.moveTo(rowNum);
                  return new SingleRow(list);
              }
  
              public void remove() {
                  throw new RuntimeException("Can not remove");
              }
          };
      }
  
      public int size() {
          return numRows;
      }
  
      public void flush() {
          if (list != null) {
              list.flush();
          }
      }
  
      public String getColumnName(final int i) {
          if (list != null) {
             return list.getColumnName(i);
         }
         return "";
     }
 
     public String getIndirectColumnName(final int index) {
         if (list != null) {
             return list.getIndirectColumnName(index);
         }
         return "";
     }
 
     public int numColumns() {
         if (list != null) {
             return list.numColumns();
         }
         return 0;
     }
 
     public int numIndirectColumns() {
         if (list != null) {
             return list.numIndirectColumns();
         }
         return 0;
     }
 
 }