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1
10
11 package com.triactive.jdo.store;
12
13 import com.triactive.jdo.PersistenceManager;
14 import com.triactive.jdo.StateManager;
15 import com.triactive.jdo.model.ClassMetaData;
16 import com.triactive.jdo.model.CollectionMetaData;
17 import com.triactive.jdo.model.FieldMetaData;
18 import com.triactive.jdo.util.IntArrayList;
19 import java.lang.reflect.Field  ;
20 import java.util.Collection ;
21 import java.util.Iterator ;
22 import javax.jdo.JDOUserException;
23
24
25 class InverseSetStore extends AbstractSetStore
26 {
27 private final int ownerFieldNumber;
28
29 public InverseSetStore(FieldMetaData fmd, StoreManager storeMgr)
30 {
31 this.storeMgr = storeMgr;
32
33 dba = storeMgr.getDatabaseAdapter();
34
35 Field field = fmd.getField();
36 ClassMetaData cmd = fmd.getClassMetaData();
37 CollectionMetaData colmd = fmd.getCollectionMetaData();
38 if (colmd == null)
39 throw new JDOUserException("No collection metadata found in " + fmd);
40
41 elementType = colmd.getElementType();
42 elementsAreEmbedded = false;
43
44 FieldMetaData eofmd = colmd.getOwnerField();
45
46 FieldMetaData omd = eofmd.getOwnedByCollection();
47 if (omd == null || !omd.equals(fmd))
48 throw new InvalidMetaDataRelationshipException(fmd, "owner-field", eofmd, "collection-field");
49
50 String ownerFieldName = eofmd.getName();
51
52 ClassMetaData emd = eofmd.getClassMetaData();
53 ownerFieldNumber = emd.getAbsoluteFieldNumber(ownerFieldName);
54
55 ClassBaseTable elementTable = storeMgr.getClassBaseTable(elementType);
56
57 if (!elementTable.isFieldPersistent(ownerFieldNumber))
58 throw new JDOUserException("Non-persistent field type for collection owner field: " + field.getDeclaringClass().getName() + "." + field.getName());
59
60 Mapping m = elementTable.getFieldMapping(ownerFieldNumber);
61 if (!(m instanceof ColumnMapping) || m instanceof PostWriteProcessing)
62 throw new JDOUserException("Invalid field type for collection owner field: " + field.getDeclaringClass().getName() + "." + field.getName());
63
64 ownerMapping = (ColumnMapping)m;
65 elementMapping = (ColumnMapping)dba.getMapping(elementType);
66
67 setTable = elementTable;
68 setName = "inverseSet";
69
70 ownerColumn = ownerMapping.getColumn();
71 elementColumn = elementTable.getIDMapping().getColumn();
72
73 loadStmt = "SELECT " + elementColumn.getName() +
74 " FROM " + elementTable.getName() +
75 " WHERE " + ownerColumn.getName() + " = ?";
76 sizeStmt = "SELECT COUNT(" + elementColumn.getName() + ")" +
77 " FROM " + elementTable.getName() +
78 " WHERE " + ownerColumn.getName() + " = ?";
79 containsStmt = "SELECT " + elementColumn.getName() +
80 " FROM " + elementTable.getName() +
81 " WHERE " + ownerColumn.getName() + " = ? AND " + elementColumn.getName() + " = ?";
82 addStmt = null;
83 removeStmt = null;
84 clearStmt = null;
85
86
89 int fieldCount = emd.getInheritedFieldCount() + emd.getFieldCount();
90 IntArrayList colfn = new IntArrayList(fieldCount);
91 ColumnMapping[] colfm = new ColumnMapping[fieldCount];
92
93 boolean[] defaultFetchGroupFields = emd.getDefaultFetchGroupFieldFlags();
94
95 for (int i = 0; i < fieldCount; ++i)
96 {
97 if (defaultFetchGroupFields[i])
98 {
99 m = elementTable.getFieldMapping(i);
100
101 if (m instanceof ColumnMapping)
102 {
103 colfn.add(i);
104 colfm[i] = (ColumnMapping)m;
105 }
106 }
107 }
108
109 if (colfn.isEmpty())
110 {
111 prefetchFieldNumbers = null;
112 prefetchFieldMappings = null;
113 }
114 else
115 {
116 prefetchFieldNumbers = colfn.toArray();
117 prefetchFieldMappings = colfm;
118 }
119 }
120
121
122 public QueryStatement newQueryStatement(StateManager sm, Class candidateClass)
123 {
124 if (!elementType.isAssignableFrom(candidateClass))
125 throw new IncompatibleQueryElementTypeException(elementType, candidateClass);
126
127 ClassBaseTable candidateTable = storeMgr.getClassBaseTable(candidateClass);
128 QueryStatement stmt = dba.newQueryStatement(candidateTable);
129
130 SQLExpression ownerExpr = new ObjectExpression(stmt, stmt.getColumn(ownerColumn));
131 SQLExpression ownerVal = ownerMapping.newSQLLiteral(stmt, sm.getObject());
132
133 stmt.andCondition(ownerExpr.eq(ownerVal));
134
135 stmt.select(elementColumn);
136
137 return stmt;
138 }
139
140
141 public QueryStatement.QueryColumn
142 joinElementsTo(QueryStatement stmt,
143 QueryStatement.QueryColumn ownerIDColumn,
144 SQLIdentifier setRangeVar,
145 Class filteredElementType,
146 SQLIdentifier elementRangeVar)
147 {
148 if (!elementType.isAssignableFrom(filteredElementType))
149 throw new IncompatibleQueryElementTypeException(elementType, filteredElementType);
150
151
152 ClassBaseTable filteredElementTable = storeMgr.getClassBaseTable(filteredElementType);
153
154 stmt.newTableExpression(filteredElementTable, elementRangeVar);
155 stmt.innerJoin(ownerIDColumn, stmt.getColumn(elementRangeVar, ownerColumn));
156
157 Column elementTableIDColumn = filteredElementTable.getIDMapping().getColumn();
158
159 return stmt.getColumn(elementRangeVar, elementTableIDColumn);
160 }
161
162
163 public boolean add(StateManager sm, Object element)
164 {
165 PersistenceManager pm = sm.getPersistenceManager();
166 StateManager esm = pm.findStateManager(element);
167
168
175 if (esm == null)
176 {
177 pm.makeTransactional(element);
178 esm = pm.findStateManager(element);
179 }
180
181 boolean wasPersistent = esm.isPersistent((javax.jdo.spi.PersistenceCapable)element);
182
183
189 Object oldOwner = esm.getField(ownerFieldNumber);
190 Object newOwner = sm.getObject();
191 esm.setField(ownerFieldNumber, oldOwner, newOwner);
192 pm.makePersistent(element);
193
194 return !wasPersistent || oldOwner != newOwner;
195 }
196
197
198 public boolean remove(StateManager sm, Object element)
199 {
200 if (!validateElementForReading(sm, element))
201 return false;
202
203 PersistenceManager pm = sm.getPersistenceManager();
204 StateManager esm = pm.findStateManager(element);
205
206 Object oldOwner = esm.getField(ownerFieldNumber);
207
208 if (oldOwner != sm.getObject())
209 return false;
210 else
211 {
212 if (ownerColumn.isNullable())
213 esm.setField(ownerFieldNumber, oldOwner, null);
214 else
215 pm.deletePersistent(element);
216
217 return true;
218 }
219 }
220
221
222 public void clear(StateManager sm)
223 {
224 PersistenceManager pm = sm.getPersistenceManager();
225 Collection elements = load(sm);
226
227 if (ownerColumn.isNullable())
228 {
229 Iterator i = elements.iterator();
230
231 while (i.hasNext())
232 {
233 StateManager esm = pm.findStateManager(i.next());
234 esm.setField(ownerFieldNumber, esm.getField(ownerFieldNumber), null);
235 }
236 }
237 else
238 pm.deletePersistentAll(elements);
239 }
240 }
241 |
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