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1
23
24 package org.objectweb.medor.optim.lib;
25
26 import java.util.ArrayList  ;
27 import java.util.HashMap ;
28 import java.util.Iterator ;
29 import java.util.Map ;
30
31 import org.objectweb.medor.api.Field;
32 import org.objectweb.medor.api.MedorException;
33 import org.objectweb.medor.expression.api.Expression;
34 import org.objectweb.medor.expression.api.Operator;
35 import org.objectweb.medor.filter.api.FieldOperand;
36 import org.objectweb.medor.query.api.CalculatedField;
37 import org.objectweb.medor.query.api.FilteredQueryTree;
38 import org.objectweb.medor.query.api.NestQueryNode;
39 import org.objectweb.medor.query.api.NestedField;
40 import org.objectweb.medor.query.api.PropagatedField;
41 import org.objectweb.medor.query.api.QueryLeaf;
42 import org.objectweb.medor.query.api.QueryNode;
43 import org.objectweb.medor.query.api.QueryTree;
44 import org.objectweb.medor.query.api.QueryTreeField;
45 import org.objectweb.medor.query.lib.QueryTreePrinter;
46 import org.objectweb.medor.query.rdb.api.RdbExpField;
47 import org.objectweb.medor.query.rdb.api.RdbExpQueryLeaf;
48 import org.objectweb.util.monolog.api.BasicLevel;
49
50
58 public class DropUnusedProjFieldsRule extends BasicRule {
59
60 public DropUnusedProjFieldsRule() {
61 super("DropUnusedProjFieldsRule");
62 }
63
64
68 public QueryTree rewrite(QueryTree qt, QueryNode _parent)
69 throws MedorException {
70 debug = log != null && log.isLoggable(BasicLevel.DEBUG);
71 if (qt instanceof QueryNode) {
72 Field[] myFields = qt.getTupleStructure().getFields();
73 dropUnusedProjFields(qt, array2arrayList(myFields));
74 }
75 return qt;
76 }
77
78 private void dropUnusedProjFields(QueryTree qt,
79 ArrayList wanted)
80 throws MedorException {
81 if (debug) log.log(BasicLevel.DEBUG, "-Current node is " + qt);
82 if (debug) log.log(BasicLevel.DEBUG, "Query tree before dropping fields:");
83 if (debug) QueryTreePrinter.printQueryTree(qt, log);
84
85 Map qt2ReqFields = new HashMap ();
86
87 if (debug) log.log(BasicLevel.DEBUG, " Drop unused fields from projected fields in according to usage");
88 Field[] myFields = qt.getTupleStructure().getFields();
90 for (int i = 0; i < myFields.length; i++) {
91 if (debug) log.log(BasicLevel.DEBUG, "\tfield=" + myFields[i].getName());
92 if (!wanted.contains(myFields[i])) {
93 if (debug) log.log(BasicLevel.DEBUG, "\tDropping field " + myFields[i].getName() + " (" + myFields[i] + ") " + " qt=" + qt);
94 if (qt instanceof QueryNode) {
95 ((QueryNode) qt).removeField(myFields[i].getName());
96 }
97 else if (qt instanceof RdbExpQueryLeaf)
98 ((RdbExpQueryLeaf) qt).removeRdbField(
99 (RdbExpField) myFields[i]);
100 }
101 }
102
103 if (debug) log.log(BasicLevel.DEBUG, "Query tree after dropping fields:");
104 if (debug) QueryTreePrinter.printQueryTree(qt, log);
105
106 if (qt instanceof QueryLeaf)
107 return;
108
109 if (debug) log.log(BasicLevel.DEBUG, " calculate the Map (qt child => { field }");
111 myFields = qt.getTupleStructure().getFields();
112 for (int i = 0; i < myFields.length; i++) {
113 if (debug) log.log(BasicLevel.DEBUG, "\tfield " + myFields[i].getName() + " is " + myFields[i]);
114 if (myFields[i] instanceof CalculatedField)
115 addFieldFromExpression(qt2ReqFields,
116 ((CalculatedField) myFields[i]).getExpression());
117 else
118 addFieldInMap(qt2ReqFields, (QueryTreeField) myFields[i]);
119 }
121
122 if (qt instanceof NestQueryNode) {
123 myFields = ((NestQueryNode) qt).getNestingFields();
124 for (int i = 0; i < myFields.length; i++) {
125 addAncestorsToMap(qt2ReqFields, new Field[] {(QueryTreeField) myFields[i]});
126 }
127 }
128
129 if (debug) log.log(BasicLevel.DEBUG, "Add field from the query filter");
130 addFieldFromExpression(qt2ReqFields,
131 ((FilteredQueryTree) qt).getQueryFilter());
132
133 if (debug) log.log(BasicLevel.DEBUG, "Recall on children");
134 for (Iterator it = qt2ReqFields.entrySet().iterator(); it.hasNext();) {
136 Map.Entry e = (Map.Entry ) it.next();
137 dropUnusedProjFields((QueryTree) e.getKey(),
138 (ArrayList ) e.getValue());
139 }
140 }
141
142
145 private void addFieldFromExpression(Map qt2ReqFields, Expression exp) {
146 if (exp instanceof FieldOperand) {
147 QueryTreeField f = (QueryTreeField) ((FieldOperand) exp).getField();
148 QueryTree qt = f.getQueryTree();
149 ArrayList fields = (ArrayList ) qt2ReqFields.get(qt);
150 if (fields == null) {
151 if (debug) log.log(BasicLevel.DEBUG, "addFieldFromExpression: FieldOperand, new Qt in map");
152 fields = new ArrayList (1);
153 fields.add(f);
154 qt2ReqFields.put(qt, fields);
155 }
156 else if (!(fields.contains(f))) {
157 if (debug) log.log(BasicLevel.DEBUG, "addFieldFromExpression: FieldOperand, Qt exists in map");
158 fields.add(f);
159 } else {
160 if (debug) log.log(BasicLevel.DEBUG, "addFieldFromExpression: FieldOperand already referenced");
161 }
162 } else if (exp instanceof Operator) {
163 if (debug) log.log(BasicLevel.DEBUG, "addFieldFromExpression: Operator");
164 for(int i=0; i<((Operator) exp).getOperandNumber(); i++) {
165 addFieldFromExpression(qt2ReqFields,
166 ((Operator) exp).getExpression(i));
167 }
168 }
169 }
170
171 private void addFieldInMap(Map qt2ReqFields, QueryTreeField field) {
172 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: field " + field);
173 Field[] anc = null;
174 if (field instanceof PropagatedField) {
175 anc = ((PropagatedField) field).getPreviousFields();
176 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: PropagatedField " + field.getName());
177 }
178 else if (field instanceof NestedField) {
179 anc = ((NestedField) field).getFields();
180 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: NestedField " + field.getName());
181 }
182 else
183 anc = new Field[0];
184 addAncestorsToMap(qt2ReqFields, anc);
185 }
186
187 private void addAncestorsToMap(Map qt2ReqFields, Field[] anc) {
188 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: registered previous, nb=" + anc.length);
189 for (int i = 0; i < anc.length; i++) {
190 QueryTree qt = ((QueryTreeField) anc[i]).getQueryTree();
191 ArrayList fields = (ArrayList ) qt2ReqFields.get(qt);
192 if (fields == null) {
193 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: Field, new Qt exists map");
194 fields = new ArrayList (1);
195 fields.add(anc[i]);
196 qt2ReqFields.put(qt, fields);
197 }
198 else if (!(fields.contains(anc[i]))) {
199 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: Field, Qt exists in map");
200 fields.add(anc[i]);
201 }
202 else {
203 if (debug) log.log(BasicLevel.DEBUG, "addFieldInMap: Field already referenced");
204 }
205 }
206 }
207
208 private ArrayList array2arrayList(Object [] array) {
209 ArrayList alist = new ArrayList (array.length);
210 for (int i = 0; i < array.length; i++) {
211 alist.add(array[i]);
212 }
213 return alist;
214 }
215 }
216 |
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