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1
22
23 package org.xquark.extractor.algebra;
24
25 import java.util.*;
26
27 import org.xquark.extractor.common.SqlWrapperException;
28 import org.xquark.extractor.sql.SqlExpression;
29 import org.apache.commons.collections.set.ListOrderedSet;;
30
31 public final class Join extends Expression implements Relation, PredicateHolder {
32 private static final String  RCSRevision = "$Revision: 1.6 $";
33 private static final String RCSName = "$Name: $";
34
35 protected List _predicateList;
36 protected List _operandList;
37 protected List _keys;
38
39 private Set _visibleTableInstance = ListOrderedSet.decorate(new HashSet());
40
41
42 public Join(List operandList, List predicateList) {
43 setOperandList(operandList);
44 setPredicateList(predicateList);
45 }
46
47 public Join() {
48 _operandList = new ArrayList();
49 }
50
51 synchronized Object clone(Map clonedExprs) throws CloneNotSupportedException {
52 Join retVal = (Join) super.clone(clonedExprs);
53 retVal.setOperandList(AlgebraTools.clone(getOperandList(), clonedExprs));
54 retVal.setPredicateList(AlgebraTools.clone(getPredicateList(), clonedExprs));
55
56 clonedExprs.put(this, retVal);
57 return retVal;
58 }
59
60 public List getPredicateList() {
61 return _predicateList;
62 }
63
64 public void setPredicateList(List predicateList) {
65 _predicateList = predicateList;
66
67 if (null != _predicateList) {
68 Iterator itr;
69 itr = _predicateList.iterator();
70 while (itr.hasNext()) {
71 ((Expression) itr.next()).setFather(this);
72 }
73 }
74 }
75
76 public void addPredicate(Expression predicate) {
77 if (null == predicate) {
78 return;
79 }
80
81 if (null == _predicateList) {
82 _predicateList = new ArrayList();
83 }
84
85 _predicateList.add(predicate);
86 predicate.setFather(this);
87 }
88
89 public void addPredicateList(List predicateList) {
90 if (null == predicateList)
91 return;
92
93 if (null == _predicateList) {
94 _predicateList = new ArrayList();
95 }
96
97 _predicateList.addAll(predicateList);
98
99 Expression predicate = null;
100 for (int i = 0; i < predicateList.size(); i++) {
101 predicate = (Expression) predicateList.get(i);
102 predicate.setFather(this);
103 }
104
105 }
106
107 public void removePredicate(Expression predicate) {
108 _predicateList.remove(predicate);
109 }
110
111
115 public List getOperandList() {
116 return _operandList;
117 }
118
119
125 public void setOperandList(List aOperandList) {
126 _operandList = aOperandList;
127 if (null != _operandList) {
128 Iterator itr;
129 itr = _operandList.iterator();
130 while (itr.hasNext()) {
131 ((Expression) itr.next()).setFather(this);
132 }
133 }
134 _visibleTableInstance.clear();
135 }
136
137 public void addOperandList(List aOperandList) {
138 if (null != aOperandList) {
139 if (null == _operandList) {
140 _operandList = new ArrayList();
141 }
142 _operandList.addAll(aOperandList);
143
144 Iterator itr;
145 itr = _operandList.iterator();
146 while (itr.hasNext()) {
147 ((Expression) itr.next()).setFather(this);
148 }
149 }
150 _visibleTableInstance.clear();
151 }
152
153 public List getOperands() {
154 return _operandList;
155 }
156
157 public void addOperand(Expression relation) {
158 if (null == relation)
159 return;
160 if (null == _operandList)
161 _operandList = new ArrayList();
162 _operandList.add(relation);
163 relation.setFather(this);
164 _visibleTableInstance.clear();
165 }
166
167 public boolean predicateUp(Expression predicate) {
168 return false;
169 }
170
171 public Set providedTableInstances() {
172 return visibleTableInstances();
173 };
174
175 public Set visibleTableInstances() {
176 if (_visibleTableInstance.isEmpty()) {
177 Relation operand = null;
178 for (int i = 0; i < _operandList.size(); i++) {
179 operand = (Relation) _operandList.get(i);
180 _visibleTableInstance.addAll(operand.providedTableInstances());
181 }
182 }
183 return _visibleTableInstance;
184 }
185
186 public AttributeExpression findNonNullAttribute() {
187 Iterator it = _operandList.iterator();
188 AttributeExpression ret = null;
189
190 while (it.hasNext() && ret == null) {
191 ret = ((Relation) it.next()).findNonNullAttribute();
192 }
193 return ret;
194 }
195
196 public List getItems() {
197 return null;
198 }
199
200 public void setKeys(List keys) {
201 _keys = keys;
202 }
203
204 public List getKeys() {
205 return _keys;
206 }
207
208 public List nameTest(String name) { return null;}
209
210 public boolean replaceChild(Expression oldChild, Expression newChild) {
211 boolean retVal = false;
212
213 List list = getPredicateList();
214 Expression expr = null;
215
216 if (null != list) {
217 for (int i = 0; i < list.size(); i++) {
218 expr = (Expression) list.get(i);
219 if (expr.equals(oldChild)) {
220 list.set(i, newChild);
221 newChild.setFather(this);
222 retVal = true;
223 break;
224 }
225 }
226 }
227
228 list = getOperandList();
229
230 expr = null;
231 for (int i = 0; i < list.size(); i++) {
232 expr = (Expression) list.get(i);
233 if (expr.equals(oldChild)) {
234 list.set(i, newChild);
235 newChild.setFather(this);
236 retVal = true;
237 break;
238 }
239 }
240
241 return retVal;
242 }
243
244 public SqlExpression accept(GenSqlVisitor visitor) throws SqlWrapperException {
245 return visitor.visit(this);
246 }
247
248 public void accept(AlgebraVisitor visitor) throws SqlWrapperException {
249 visitor.visit(this);
250 }
251
252
255 public boolean deepEquals(Object o) {
256 if (o instanceof Join) {
257 Join cast = (Join) o;
258 return AlgebraTools.areExprListEquivalent(_operandList, cast.getOperandList()) && AlgebraTools.areExprListEquivalent(_predicateList, cast.getPredicateList());
259 }
260 return false;
261 }
262 }
263 |
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