PhraseRepresentation


1   package com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.condition;
2   
3   import com.daffodilwoods.database.resource.DException;
4   import com.daffodilwoods.daffodildb.server.sql99.dql.iterator._Iterator;
5   import com.daffodilwoods.database.sqlinitiator._Order;
6   import com.daffodilwoods.daffodildb.server.sql99.fulltext.dml.
7       _FullTextIndexInformation;
8   import com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.iterator.
9       Rank1FTIterator;
10  import com.daffodilwoods.daffodildb.server.sql99.utils._Reference;
11  import com.daffodilwoods.daffodildb.utils.field.FieldBase;
12  import com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.iterator.
13      Rank2FTIterator;
14  import com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.iterator.
15      Rank3FTIterator;
16  import com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.iterator.
17      Rank4FTIterator;
18  import com.daffodilwoods.daffodildb.server.sql99.common.
19      GeneralPurposeStaticClass;
20  import com.daffodilwoods.daffodildb.server.sql99.common.Datatypes;
21  import com.daffodilwoods.daffodildb.server.sql99.dql.iterator.set.
22      UnionAllIterator;
23  import com.daffodilwoods.daffodildb.server.sql99.fulltext.dql.iterator.
24      AnyKeyWordsIterator;
25  
26  /**
27   * It represents plan which is generated when search pattern is a sentence.i.e
28   * combination of more than one word. eg 'Daffodil is a software company'
29   * It provides functionality of getting ResultSet.which provides those documnets
30   * in which search pattern is present.
31   * <p>Title: </p>
32   * <p>Description: </p>
33   * <p>Copyright: Copyright (c) 2003</p>
34   * <p>Company: </p>
35   * @author not attributable
36   * @version 1.0
37   */
38  
39  public class PhraseRepresentation
40      implements _Word {
41    /**
42     * This represents list of word that form a complete search pattern
43     */
44    WordRepresentation[] wordList;
45    private _Order order;
46  
47    /**
48     * It represents name of column against which searched column is searched
49     */
50    String   columnName;
51  
52    public PhraseRepresentation(WordRepresentation[] wordList) {
53      this.wordList = wordList;
54    }
55  
56    /**
57     * This method used to get Type of plan.It is required by plan merger to merge
58     * two plan either by AND and OR logical operator.
59     */
60    public int getType() {
61      return PredicateConstant.phrase;
62    }
63  
64    /**
65     * It is required to get columnName of searched column against which search
66     * pattern is searched.
67     * @return columnName
68     * @throws DException
69     */
70    public String   getColumn() throws DException {
71      return columnName = wordList[0].getColumn();
72    }
73  
74    /**
75     * It is used to set columnName of searched column against which search
76     * pattern is searched.
77     * @param colName
78     * @throws DException
79     */
80    public void setColumn(String   colName) throws DException {
81      for (int i = 0; i < wordList.length; i++) {
82        wordList[i].setColumn(colName);
83      }
84    }
85  
86    /**
87     * It is used to get list of word that form a search pattern
88     * @return
89     * @throws DException
90     */
91    public WordRepresentation[] getWord() throws DException {
92      return wordList;
93    }
94  
95    public double getCost() throws DException {
96      return 0.0;
97    }
98  
99    public double getCost(Object   session) throws DException {
100     return 0.0;
101   }
102 
103   /**
104    * It is required for plan execution.It gives resultset,which provides those
105    * documents in which search pattern is present.For each individual word in
106    * search pattern we take resultset from token table and location table and also take
107    * unknown references of location condtion, then make final resultset.
108    * @param session
109    * @return
110    * @throws DException
111    */
112   public _Iterator execute(Object   session) throws DException {
113     int length = wordList.length;
114     _Iterator tokenIterator[] = new _Iterator[length];
115     _Iterator locationIterator[] = new _Iterator[length];
116     _Reference fpkReference[] = new _Reference[length];
117     FieldBase[] keyWords = new FieldBase[length];
118     for (int i = 0; i < length; i++) {
119       tokenIterator[i] = wordList[i].getTokenIterator(session);
120       locationIterator[i] = wordList[i].getLocationIterator(session);
121       fpkReference[i] = wordList[i].getFpkReference();
122       keyWords[i] = (FieldBase) wordList[i].getKeyWords();
123     }
124     /** All 4 iterators are used to handle the case like:
125      * phrase: "daffodil software ltd"
126      * it should fetch records which has all the 3 words above
127      * records with exact match
128      * records with any word
129      * records with words without 0 gap
130      * and records with any sequence of above words.
131  */
132     _Iterator rank1 = new Rank1FTIterator(tokenIterator, locationIterator,
133                                           fpkReference, keyWords);
134     _Iterator rank2 = new Rank2FTIterator(tokenIterator, locationIterator,
135                                           fpkReference, keyWords);
136 
137     _Iterator rank3 = new Rank3FTIterator(tokenIterator, locationIterator,
138                                           fpkReference, keyWords);
139     _Iterator rank4 = new Rank4FTIterator(tokenIterator, locationIterator,
140                                           fpkReference, keyWords);
141     return getUnionIterator(rank1, rank2, rank3, rank4);
142   }
143 
144   private _Iterator getUnionIterator(_Iterator rank1, _Iterator rank2,
145                                      _Iterator rank3, _Iterator rank4) throws
146       DException {
147     int[] appropriateDataType = new int[] {
148         Datatypes.LONGSIZE};
149     _Reference[] leftReferences = new _Reference[] {
150         GeneralPurposeStaticClass.getColumnDetails("documentId")};
151     _Reference[] rightReferences = new _Reference[] {
152         GeneralPurposeStaticClass.getColumnDetails("documentId")};
153     _Reference[] orderLeftColumnDetails = new _Reference[] {
154         GeneralPurposeStaticClass.getColumnDetails("documentId")};
155     _Reference[] orderRightColumnDetails = new _Reference[] {
156         GeneralPurposeStaticClass.getColumnDetails("documentId")};
157             UnionAllIterator iter = new UnionAllIterator(rank1, rank2, leftReferences,
158                                                  rightReferences,
159                                                  appropriateDataType,
160                                                  appropriateDataType,
161                                                  orderLeftColumnDetails,
162                                                  orderRightColumnDetails);
163     _Reference[] leftReferences1 = new _Reference[] {
164         GeneralPurposeStaticClass.getColumnDetails("documentId")};
165     _Reference[] rightReferences1 = new _Reference[] {
166         GeneralPurposeStaticClass.getColumnDetails("documentId")};
167     _Reference[] orderLeftColumnDetails1 = new _Reference[] {
168         GeneralPurposeStaticClass.getColumnDetails("documentId")};
169     _Reference[] orderRightColumnDetails1 = new _Reference[] {
170         GeneralPurposeStaticClass.getColumnDetails("documentId")};
171     UnionAllIterator iter1 = new UnionAllIterator(rank3, rank4, leftReferences1,
172                                                   rightReferences1,
173                                                   appropriateDataType,
174                                                   appropriateDataType,
175                                                   orderLeftColumnDetails1,
176                                                   orderRightColumnDetails1);
177     _Reference[] leftReferences2 = new _Reference[] {
178         GeneralPurposeStaticClass.getColumnDetails("documentId")};
179     _Reference[] rightReferences2 = new _Reference[] {
180         GeneralPurposeStaticClass.getColumnDetails("documentId")};
181     _Reference[] orderLeftColumnDetails2 = new _Reference[] {
182         GeneralPurposeStaticClass.getColumnDetails("documentId")};
183     _Reference[] orderRightColumnDetails2 = new _Reference[] {
184         GeneralPurposeStaticClass.getColumnDetails("documentId")};
185     return new UnionAllIterator(iter, iter1, leftReferences2, rightReferences2,
186                                 appropriateDataType, appropriateDataType,
187                                 orderLeftColumnDetails2,
188                                 orderRightColumnDetails2);
189 
190   }
191 
192   public double getEstimatedRow() throws DException {
193     return 1;
194   }
195 
196   public void setOrder(_Order order) throws DException {
197     this.order = order;
198   }
199 
200   public _Order getOrder() throws DException {
201     return order;
202   }
203 
204   /**
205    * It is required to get ResultSet which provide documents in which search
206    * pattern are present.It provides documents in sorted order.
207    * @param indexTable
208    * @return
209    * @throws DException
210    */
211   public _Iterator executeForSortedResult(Object   indexTable) throws DException {
212     _Iterator tokenIterator[] = getTokenIterator(indexTable);
213     FieldBase keyWord[] = getKeyWords(indexTable);
214     AnyKeyWordsIterator iter = new AnyKeyWordsIterator(
215         tokenIterator, keyWord);
216     return iter;
217 
218   }
219 
220   /**
221    * This method is required to get resultset on every word in serach pattern which is
222    * to be searched. ResultSet of every word provide desired document
223    * in which that search pattern is present.
224    * @param session
225    * @return _Iterator[]
226    * @throws DException
227    */
228   private _Iterator[] getTokenIterator(Object   session) throws DException {
229     int length = wordList.length;
230     _Iterator tokenIterator[] = new _Iterator[length];
231     for (int i = 0; i < length; i++) {
232       tokenIterator[i] = wordList[i].getTokenIterator(session);
233     }
234     return tokenIterator;
235   }
236 
237   /**
238    * Returns the single words.
239    * @param session
240    * @return FieldBase
241    * @throws DException
242    */
243   private FieldBase[] getKeyWords(Object   session) throws DException {
244     int length = wordList.length;
245     FieldBase[] KeyWords = new FieldBase[length];
246     for (int i = 0; i < length; i++) {
247       KeyWords[i] = (FieldBase) wordList[i].getKeyWords();
248     }
249     return KeyWords;
250   }
251 
252 }
253
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