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1
10
11 package com.triactive.jdo.store;
12
13 import com.triactive.jdo.PersistenceManager;
14 import com.triactive.jdo.model.ClassMetaData;
15 import com.triactive.jdo.util.IntArrayList;
16 import java.util.HashMap  ;
17 import java.util.Iterator ;
18 import javax.jdo.Extent;
19 import org.apache.log4j.Category;
20
21
22
30
31 class ClassBaseTableExtent implements Extent, Queryable
32 {
33 private static final Category LOG = Category.getInstance(ClassBaseTableExtent.class);
34
35 private final PersistenceManager pm;
36 private final ClassBaseTable table;
37 private final boolean subclasses;
38 private final StoreManager storeMgr;
39 private final DatabaseAdapter dba;
40 private final Query query;
41 private final int[] prefetchFieldNumbers;
42 private final ColumnMapping[] prefetchFieldMappings;
43
44 private HashMap queryResultsByIterator = new HashMap ();
45
46
47 public ClassBaseTableExtent(PersistenceManager pm, ClassBaseTable table, boolean subclasses)
48 {
49 this.pm = pm;
50 this.table = table;
51 this.subclasses = subclasses;
52
53 storeMgr = table.getStoreManager();
54 dba = storeMgr.getDatabaseAdapter();
55 query = storeMgr.getQuery(pm, null);
56
57 Class candidateClass = getCandidateClass();
58
59 query.setClass(candidateClass);
60 query.setCandidates(this);
61
62 ClassMetaData cmd = ClassMetaData.forClass(candidateClass);
63 int fieldCount = cmd.getInheritedFieldCount() + cmd.getFieldCount();
64 IntArrayList colfn = new IntArrayList(fieldCount);
65 ColumnMapping[] colfm = new ColumnMapping[fieldCount];
66
67 boolean[] defaultFetchGroupFields = cmd.getDefaultFetchGroupFieldFlags();
68
69 for (int i = 0; i < fieldCount; ++i)
70 {
71 if (defaultFetchGroupFields[i])
72 {
73 Mapping m = table.getFieldMapping(i);
74
75 if (m instanceof ColumnMapping)
76 {
77 colfn.add(i);
78 colfm[i] = (ColumnMapping)m;
79 }
80 }
81 }
82
83 if (colfn.isEmpty())
84 {
85 prefetchFieldNumbers = null;
86 prefetchFieldMappings = null;
87 }
88 else
89 {
90 prefetchFieldNumbers = colfn.toArray();
91 prefetchFieldMappings = colfm;
92 }
93 }
94
95
96
101
102 public Iterator iterator()
103 {
104 QueryResult qr = (QueryResult)query.execute();
105 Iterator i = qr.iterator();
106
107 queryResultsByIterator.put(i, qr);
108
109 return i;
110 }
111
112
113
119
120 public boolean hasSubclasses()
121 {
122 return subclasses;
123 }
124
125
126
132
133 public Class getCandidateClass()
134 {
135 return table.getType();
136 }
137
138
139
145
146 public javax.jdo.PersistenceManager getPersistenceManager()
147 {
148 return pm;
149 }
150
151
152
161
162 public void close(Iterator it)
163 {
164 QueryResult qr = (QueryResult)queryResultsByIterator.remove(it);
165
166 qr.close();
167 }
168
169
170
176
177 public void closeAll()
178 {
179 Iterator i = queryResultsByIterator.values().iterator();
180
181 while (i.hasNext())
182 {
183 QueryResult qr = (QueryResult)i.next();
184
185 qr.close();
186 i.remove();
187 }
188 }
189
190
191 public QueryStatement newQueryStatement(Class candidateClass)
192 {
193 Class extentType = table.getType();
194
195 if (!extentType.isAssignableFrom(candidateClass))
196 throw new IncompatibleQueryElementTypeException(extentType, candidateClass);
197
198 ClassBaseTable candidateTable = storeMgr.getClassBaseTable(candidateClass);
199 QueryStatement stmt = dba.newQueryStatement(candidateTable);
200
201 ColumnMapping idMapping = table.getIDMapping();
202 Column idColumn = idMapping.getColumn();
203
204 if (!subclasses)
205 {
206 if (!table.equals(candidateTable))
207 LOG.warn("Query over extent will never return results w/o including subclasses: extent = " + this + ", candidate class = " + candidateClass);
208
209 int classID = table.getTableID();
210
211 BooleanExpression filterByClass =
212 new OIDRangeTestExpression(stmt, stmt.getColumn(idColumn),
213 new OID(classID, 0, 0),
214 new OID(classID, OID.MAX_OBJIDHI, OID.MAX_OBJIDLO));
215
216 stmt.andCondition(filterByClass);
217 }
218
219 stmt.select(idColumn);
220
221 return stmt;
222 }
223
224
225 public Query.ResultObjectFactory newResultObjectFactory(QueryStatement stmt)
226 {
227 if (stmt.getDistinctResults() || prefetchFieldMappings == null)
228 return new PersistentIDROF(pm, getCandidateClass());
229 else
230 {
231 int[] columnNumbersByField = new int[prefetchFieldMappings.length];
232
233 for (int i = 0; i < prefetchFieldMappings.length; ++i)
234 {
235 ColumnMapping m = prefetchFieldMappings[i];
236
237 if (m != null)
238 columnNumbersByField[i] = stmt.select(m.getColumn());
239 }
240
241 return new PersistentIDROF(pm,
242 getCandidateClass(),
243 prefetchFieldNumbers,
244 prefetchFieldMappings,
245 columnNumbersByField);
246 }
247 }
248
249
250 public String toString()
251 {
252 return "Extent of " + getCandidateClass() + (subclasses ? "(including" : "(excluding") + " subclasses)";
253 }
254 }
255 |
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