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24 package org.objectweb.jalisto.se.query;
25
26 import org.objectweb.jalisto.se.api.ClassDescription;
27 import org.objectweb.jalisto.se.impl.LogicalOid;
28 import org.objectweb.jalisto.se.api.query.QueryManager;
29 import org.objectweb.jalisto.se.api.query.Query;
30 import org.objectweb.jalisto.se.api.query.Constraint;
31 import org.objectweb.jalisto.se.api.internal.SessionInternal;
32 import org.objectweb.jalisto.se.query.exception.QueryEngineException;
33 import org.objectweb.jalisto.se.query.constraint.*;
34 import org.objectweb.jalisto.se.query.execution.ExecutionTree;
35 import org.objectweb.jalisto.se.query.parameter.QueryParameter;
36 import org.objectweb.jalisto.se.query.parameter.QueryValue;
37 import org.objectweb.jalisto.se.query.parameter.SubQuery;
38 import org.objectweb.jalisto.se.query.result.QueryResultWrapper;
39 import org.objectweb.jalisto.se.query.result.ObjectSetImpl;
40 import org.objectweb.jalisto.se.api.query.ObjectSet;
41
42 import java.util.*;
43
44 public class QueryImpl implements Query {
45
46 public QueryImpl(QueryManager queryManager, Object  classConstraint) {
47 this.queryManager = queryManager;
48 this.session = (SessionInternal) queryManager.getSession();
49 this.constraints = new HashMap();
50 this.parameters = new HashMap();
51 this.subQueries = new ArrayList();
52 this.subFieldNames = new ArrayList();
53 if (queriedClass != null) {
54 try {
55 this.queriedClass = (Class ) classConstraint;
56 } catch (ClassCastException e) {
57 this.queriedClass = classConstraint.getClass();
58 }
59 }
60 }
61
62 public Constraint constrain(Object constraintObject) {
63 if (queriedClass == null) {
64 try {
65 this.queriedClass = (Class ) constraintObject;
66 } catch (ClassCastException e) {
67 this.queriedClass = constraintObject.getClass();
68 }
69 return null;
70 }
71 Constraint constraint;
72 String key = getSubFieldNamesAsKey();
73 ArrayList constraintList = (ArrayList) constraints.get(key);
74 if (constraintList == null) {
75 constraintList = new ArrayList();
76 constraints.put(key, constraintList);
77 }
78 if (constraintObject instanceof Query) {
79 constraintObject = new SubQuery((Query) constraintObject);
80 subQueries.add(constraintObject);
81 constraint = new SubQueryConstraintImpl((SubQuery) constraintObject, queriedClass.getName(), subFieldNames);
82 } else {
83 if (constraintObject instanceof QueryParameter) {
84 QueryParameter parameter = (QueryParameter) constraintObject;
85 parameters.put(parameter.getParameterName(), parameter);
86 } else if (!(constraintObject instanceof QueryValue)) {
87 constraintObject = new QueryValue(constraintObject);
88 }
89 constraint = new ValueConstraintImpl(queriedClass.getName(), subFieldNames, (QueryValue) constraintObject);
90 }
91 constraintList.add(constraint);
92 subFieldNames.clear();
93 return constraint;
94 }
95
96 private String getSubFieldNamesAsKey() {
97 StringBuffer sb = new StringBuffer ();
98 for (int i = 0; i < subFieldNames.size(); i++) {
99 sb.append(subFieldNames.get(i));
100 if (i != subFieldNames.size() - 1) {
101 sb.append("@");
102 }
103 }
104 return sb.toString();
105 }
106
107 public List constraints() {
108 throw new QueryEngineException();
109 }
110
111 public Query descend(String fieldName) {
112 subFieldNames.add(fieldName);
113 return this;
114 }
115
116 public Query orderAscending() {
117 throw new QueryEngineException();
118 }
119
120 public Query orderDescending() {
121 throw new QueryEngineException();
122 }
123
124 public Constraint getBinaryTree() {
125 HashSet roots = new HashSet();
126 Iterator constraintLists = constraints.values().iterator();
127 while (constraintLists.hasNext()) {
128 ArrayList constraintList = (ArrayList) constraintLists.next();
129 for (int i = 0; i < constraintList.size(); i++) {
130 ConstraintImpl constraint = (ConstraintImpl) constraintList.get(i);
131 roots.addAll(constraint.getRootFathers());
132 }
133 }
134 if (roots.size() > 0) {
136 Iterator rootsIterator = roots.iterator();
137 Constraint left = (Constraint) rootsIterator.next();
138 while (rootsIterator.hasNext()) {
139 Constraint right = (Constraint) rootsIterator.next();
140 left = left.or(right);
141 }
142 return left;
143 }
144 return null;
145 }
146
147 public ObjectSet execute() {
148 if (!session.currentTransaction().isActive()) {
149 throw new QueryEngineException("transaction is not active during execution of a query");
150 }
151
152 checkBindedParameters();
153 checkSubQueries();
154
155 if (tree == null) {
156 String queriedClass = getQueriedClassName();
157 tree = new ExecutionTree(getBinaryTree(), session.getMetaRepository(), queriedClass);
158 }
159
160 Set resultSet = tree.resolve(session, queryManager.getIndexManager());
161
162 tree.cleanLeaf();
163 cleanSubQueries();
164
165 ObjectSet result = new ObjectSetImpl(resultSet);
166
167 return result;
168 }
169
170 public Set getExtent(ClassDescription meta) {
171 session.currentTransaction().begin();
172 Iterator extent = session.getExtent(meta.getClassName()).readFully().iterator();
173 Set resultSet = new HashSet();
174 while (extent.hasNext()) {
175 LogicalOid floid = (LogicalOid) extent.next();
176 Object [] values = session.readObjectByOid(floid, true);
177 resultSet.add(new QueryResultWrapper(floid, values));
178 }
179 session.currentTransaction().commit();
180 return resultSet;
181 }
182
183 private void checkBindedParameters() {
184 Iterator parametersIt = parameters.values().iterator();
185 while (parametersIt.hasNext()) {
186 QueryParameter parameter = (QueryParameter) parametersIt.next();
187 if (!parameter.isBind()) {
188 throw new QueryEngineException("Parameter " + parameter.getParameterName() +
189 " is not bind during query execution");
190 }
191 }
192 }
193
194 private void checkSubQueries() {
195 for (short i = 0; i < subQueries.size(); i++) {
196 SubQuery subQuery = (SubQuery) subQueries.get(i);
197 subQuery.getTree(session.getMetaRepository());
198 }
199 }
200
201 private void cleanSubQueries() {
202 for (short i = 0; i < subQueries.size(); i++) {
203 SubQuery subQuery = (SubQuery) subQueries.get(i);
204 subQuery.deleteTree();
205 }
206 }
207
208 public void bind(String parameterName, Object value) {
209 QueryParameter parameter = (QueryParameter) parameters.get(parameterName);
210 if (parameter == null) {
211 throw new QueryEngineException("Try to bind value to non existing parameter : " + parameterName);
212 }
213 parameter.bind(value);
214 }
215
216 public HashMap getParameters() {
217 return parameters;
218 }
219
220 public ArrayList getSubQueries() {
221 return subQueries;
222 }
223
224 public String getQueriedClassName() {
225 return queriedClass.getName();
226 }
227
228 private SessionInternal session;
229 private QueryManager queryManager;
230 private Class queriedClass;
231 private HashMap constraints;
232 private HashMap parameters;
233 private ArrayList subQueries;
234 private ExecutionTree tree;
235 private ArrayList subFieldNames;
236 }
237 |
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