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1   /*
2    * Copyright 2001-2005 The Apache Software Foundation.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  package net.sf.nxqd;
17  
18  import java.util.logging.Level;
19  import java.util.logging.Logger;
20  import java.util.ArrayList;
21  import java.util.List;
22  import java.util.Map;
23  import org.w3c.dom.Document;
24  
25  /**
26   *
27   * @author <a href="mailto:webhiker@sourceforge.net">webhiker</a>
28   * @version 1.0
29   */
30  public class NxqdResults extends NxqdConsumer {
31  
32      /**
33       * The variable <code>logger</code> is used for logging events.
34       *
35       */
36      private static Logger logger = Logger.getLogger(NxqdResults.class.getName());
37  
38       protected NxqdResults(NxqdManager manager) throws NxqdException {
39  	 super(manager);
40       }
41  
42      /**
43       * Adds the specified NxqdValue to the end of the results set. Note that if the
44       * XmlResults object was created as the result of a lazy evaluation,
45       * this method throws an exception.
46       *
47       * @param value a <code>NxqdValue</code> value
48       * @exception NxqdException if an error occurs
49       */
50      public void add(NxqdValue value)
51  	throws NxqdException {
52      }
53  
54      /**
55       * If a query was processed with eager evaluation, a call to this method returns
56       * the number of values in the result set.
57       *
58       * If the query was processed with lazy evaluation, a call to this method throws
59       * an exception. 
60       *
61       * @return an <code>int</code> value
62       * @exception NxqdException if an error occurs
63       */
64      public int size()
65  	throws NxqdException {
66  	return 0;
67      }
68  
69      /**
70       * If a query was processed with eager evaluation, a call to this method resets the
71       * result set iterator, so that a subsequent call to next() method will return the
72       * first value in the result set.
73       *
74       * If the query was processed with lazy evaluation then a call to this method method
75       * throws an exception. 
76       *
77       * @exception NxqdException if an error occurs
78       */
79      public void reset()
80  	throws NxqdException {
81      }
82  
83      /**
84       * Returns true if there is another element in the results set.
85       *
86       * @return a <code>boolean</code> value
87       * @exception NxqdException if an error occurs
88       */
89      public boolean hasNext()
90  	throws NxqdException {
91  	return false;
92      }
93  
94      /**
95       * Returns true if there is a previous element in the results set.
96       *
97       * @return a <code>boolean</code> value
98       * @exception NxqdException if an error occurs
99       */
100     public boolean hasPrevious()
101 	throws NxqdException {
102 	return false;
103     }
104 
105     /**
106      * Retrieves the next value in the result set. When no more values remain in the result set,
107      * returns null.
108      *
109      * @return a <code>NxqdValue</code> value
110      * @exception NxqdException if an error occurs
111      */
112     public NxqdValue next()
113 	throws NxqdException {
114 	return null;
115     }
116 
117     /**
118      * Retrieves the previous value in the result set. When the first value in the results
119      * set has been reached, returns null
120      *
121      * @return a <code>NxqdValue</code> value
122      * @exception NxqdException if an error occurs
123      */
124     public NxqdValue previous()
125 	throws NxqdException {
126 	return null;
127     }
128 
129     /**
130      * Returns the current element in the results set without moving the internal iterator.
131      *
132      * @return a <code>NxqdValue</code> value
133      * @exception NxqdException if an error occurs
134      */
135     public NxqdValue peek()
136 	throws NxqdException {
137 	return null;
138     }
139 
140 }
141