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1
23
24
27 package org.objectweb.medor.eval.lib;
28
29 import org.objectweb.medor.api.MedorException;
30 import org.objectweb.medor.api.TupleStructure;
31 import org.objectweb.medor.eval.api.BinaryEvaluatedTC;
32 import org.objectweb.medor.eval.api.NodeEvaluator;
33 import org.objectweb.medor.expression.api.ParameterOperand;
34 import org.objectweb.medor.expression.api.VariableOperand;
35 import org.objectweb.medor.expression.lib.BasicVariableOperand;
36 import org.objectweb.medor.query.api.QueryNode;
37 import org.objectweb.medor.tuple.api.Tuple;
38 import org.objectweb.medor.tuple.api.TupleCollection;
39 import org.objectweb.medor.tuple.lib.MemoryTuple;
40
41
42
46 public class CartesianEvaluatedTC
47 extends BasicBinaryEvalutedTC
48 implements BinaryEvaluatedTC {
49
50 private QueryNode query;
51 private TupleCollection leftTC,rightTC;
52 private ParameterOperand[] parameters;
53 private Tuple currentBuffer;
54 private Tuple leftTuple, rightTuple;
55 private VariableOperand[] operandBuffers;
56 private int cursor,size,leftTCSize,rightTCSize;
57
58 public CartesianEvaluatedTC(QueryNode query, NodeEvaluator leftNodeEvaluator, NodeEvaluator rightNodeEvaluator, ParameterOperand[] parameters) throws MedorException {
59 this.parameters = parameters;
60
61 leftTCSize = leftNodeEvaluator.getQueryNode().getTupleStructure().getSize();
63 rightTCSize = rightNodeEvaluator.getQueryNode().getTupleStructure().getSize();
64 size = query.getTupleStructure().getSize();
65
66 operandBuffers = new BasicVariableOperand[size];
68 currentBuffer = new MemoryTuple(operandBuffers);
69
70 rightTC = rightNodeEvaluator.fetchData(parameters);
72 leftTC = leftNodeEvaluator.fetchData(parameters);
73 if (isEmpty()) {
74 cursor = -2;
75 } else {
76 init();
77 }
78 }
79
80 public void close() throws MedorException {
81 super.close();
82 if (leftTC != null) {
83 leftTC.close();
84 }
85 if (rightTC != null) {
86 rightTC.close();
87 }
88 }
89
90 public TupleStructure getMetaData() throws MedorException {
91 if (closed) {
92 throw new MedorException("Impossible to use a closed TupleCollection");
93 }
94 return query.getTupleStructure();
95 }
96
97 public boolean isLast() throws MedorException {
98 if (closed) {
99 throw new MedorException("Impossible to use a closed TupleCollection");
100 }
101 return ((rightTC.isLast()) && (leftTC.isLast()));
102 }
103
104 private void init() throws MedorException {
106 leftTC.first();
107 rightTC.first();
108 leftTuple = leftTC.getTuple();
109 rightTuple = rightTC.getTuple();
110 fixeTheLeftResult();
111 fixeTheRightResult();
112 cursor = 1;
113 }
114
115 public boolean next() throws MedorException {
116 if (closed) {
117 throw new MedorException("Impossible to use a closed TupleCollection");
118 }
119 boolean moved = false;
120 if (isLast()) {
121 moved = false;
122 } else {
123 moved = true;
124 cursor++;
125 if (rightTC.next()) {
126 leftTuple = leftTC.getTuple();
127 rightTuple = rightTC.getTuple();
128 fixeTheRightResult();
129 } else {
130 if (leftTC.next()) {
131 rightTC.first();
132 rightTuple = rightTC.getTuple();
133 leftTuple = leftTC.getTuple();
134 fixeTheLeftResult();
135 fixeTheRightResult();
136 }
137 }
138 }
139 return moved;
140 }
141
142 public void first() throws MedorException {
143 if (closed) {
144 throw new MedorException("Impossible to use a closed TupleCollection");
145 }
146 init();
148 }
149
150 public int getRow() throws MedorException {
151 if (closed) {
152 throw new MedorException("Impossible to use a closed TupleCollection");
153 }
154 return cursor;
155 }
156
157 public Tuple getTuple() throws MedorException {
158 if (closed) {
159 throw new MedorException("Impossible to use a closed TupleCollection");
160 }
161 if (!isEmpty() && (getRow() >= 1))
162 return currentBuffer;
163 else
164 throw new MedorException(" No elements fetched in this TupleCollection " + getRow());
165 }
166
167 public synchronized Tuple getTuple(int numTuple) throws MedorException {
168 if (closed) {
169 throw new MedorException("Impossible to use a closed TupleCollection");
170 }
171 return getTuple();
173 }
174
175 public boolean isEmpty() throws MedorException{
176 if (closed) {
177 throw new MedorException("Impossible to use a closed TupleCollection");
178 }
179 return ((leftTC.isEmpty()) && (rightTC.isEmpty()));
180 }
181
182 public boolean row(int numTuple) throws MedorException {
183 if (closed) {
184 throw new MedorException("Impossible to use a closed TupleCollection");
185 }
186 first();
187 int cpt = 1;
188 boolean go = true;
189 while ((cpt <= numTuple) && (cpt > 1) && go) {
190 if (!next()) go = false;
191 }
192 if (!go)
193 return false;
194 else {
195 cursor = numTuple;
196 return true;
197 }
198
199 }
200
201 private void fixeTheLeftResult() throws MedorException {
202 for (int cpt = 0; (cpt < leftTCSize); cpt++) {
203 operandBuffers[cpt] = (VariableOperand)leftTuple.getLikeOperand(cpt + 1);
204 }
205 }
206
207 private void fixeTheRightResult() throws MedorException {
208 for (int cpt = leftTCSize; (cpt < size); cpt++) {
209 operandBuffers[cpt] = (VariableOperand)rightTuple.getLikeOperand(cpt - leftTCSize + 1);
210 }
211 }
212
213 public int getLeftTCCursor() throws MedorException {
214 if (closed) {
215 throw new MedorException("Impossible to use a closed TupleCollection");
216 }
217 return leftTC.getRow();
218 }
219
220 public int getRightTCCursor() throws MedorException {
221 if (closed) {
222 throw new MedorException("Impossible to use a closed TupleCollection");
223 }
224 return rightTC.getRow();
225 }
226 }
227 |
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