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1
6 package com.jofti.tree;
7
8
9
10 import java.util.Map  ;
11 import java.util.Stack ;
12
13 import com.jofti.btree.ValueObject;
14 import com.jofti.core.INameSpaceAware;
15 import com.jofti.core.IParsedQuery;
16 import com.jofti.core.IPredicate;
17 import com.jofti.exception.JoftiException;
18 import com.jofti.parser.AttributeValueParser;
19 import com.jofti.parser.CommonLexerTokenTypes;
20 import com.jofti.parser.Operator;
21 import com.jofti.parser.StackPredicate;
22 import com.jofti.util.FastStack;
23 import com.jofti.util.ObjectProcedureAdapter;
24 import com.jofti.util.OpenHashMap;
25
26
31 public abstract class AbstractMatchingEngine implements MatchingEngine {
32
33
34
35
36 protected static final int OR = CommonLexerTokenTypes.OR;
38 protected static final int AND = CommonLexerTokenTypes.AND;
39
40
41 protected AttributeValueParser attributeValueParser = new AttributeValueParser();;
42
43
44
45
46
47
48 protected Map addAllOpen(final OpenHashMap large, final OpenHashMap smaller){
49 smaller.forEachPair( new ObjectProcedureAdapter(){
51 public boolean apply(Object key, Object value){
52 if (!large.containsKey(key)){
53 large.put(key, value);
54 }
55 return true;
56 }
57 });
58
59 return large;
60 }
61
62
63 protected Map retainAllOpen(final OpenHashMap large, final OpenHashMap smaller){
64
65 smaller.forEachPair( new ObjectProcedureAdapter(){
66 public boolean apply(Object key, Object value){
67 if (!large.containsKey(key)){
68 smaller.remove(key);
69 }
70 return true;
71 }
72 });
73
74 return smaller;
75 }
76
77 protected Map andResults(Map map1, Map map2){
78 if (map1.size() > map2.size()){
79 return retainAllOpen((OpenHashMap)map1, (OpenHashMap)map2);
80 }else{
81 return retainAllOpen((OpenHashMap)map2, (OpenHashMap)map1);
82 }
83 }
84
85
86 protected Map orResults(Map map1, Map map2){
87 if (map1.size() > map2.size()){
88 return addAllOpen((OpenHashMap)map1, (OpenHashMap)map2);
89 }else{
90 return addAllOpen((OpenHashMap)map2, (OpenHashMap)map1);
91 }
92 }
93
94 protected Map resultJunction(Map map1, Operator op, Map map2){
96
97
98 switch (op.getOperator()) {
99 case OR:
100 if (map1.size() ==0) {
101 return map2;
102 }else if (map2.size() ==0){
103 return map1;
104 }
105 return orResults(map1,map2);
106 case AND:
107 if ((map1.size() ==0 || map2.size() ==0)){
108 return new OpenHashMap(1);
109 }
110 return andResults(map1,map2);
111 default:
112 return new OpenHashMap(1);
113 }
114
115 }
116
117
118 protected Map processPredicates(Stack predicates, Class className, Object nameSpace, Map aliasMap,TreeIndex index, Map namedParameters) throws JoftiException{
119
120 Map firstResults = null;
121 Map returnResults =null;
122 IPredicate first =null;
123
124 FastStack predicateStack = null;
125 if (predicates.size() == 1){
126 first = (IPredicate)predicates.peek();
127 }
128 else{
129 predicateStack = new FastStack();
130 predicateStack.addAll(predicates);
131 first = (IPredicate)predicateStack.pop();
132 }
133
134
135
136 if (first.getType() ==1){
137 firstResults = processPredicates(((StackPredicate)first).getPredicateStack(), className, nameSpace, aliasMap,index, namedParameters);
138 }else{
139 firstResults = runPredicate(first, className, nameSpace,aliasMap,index, namedParameters);
140 }
141
142
143 if (predicateStack == null || predicateStack.size() ==0){
144 returnResults = firstResults;
145 }else if (predicateStack.size() %2 == 0 && predicateStack.size() != 0){
146 returnResults = processRemainder(firstResults, predicateStack, className, nameSpace,aliasMap, index, namedParameters);
147 }else if (predicateStack.size() %2 == 1){
148 throw new JoftiException("we seem to have a hanging operator or predicate " );
149 }
150 return returnResults;
152
153
154 }
155
156 protected Map processQuery(IParsedQuery query,TreeIndex index) throws JoftiException{
157
158
159
161 Stack predicates = query.getPredicates();
162
163 Object nameSpace = null;
164 if (((INameSpaceAware)query).getNameSpace() != null){
165 nameSpace =((INameSpaceAware)query).getNameSpace();
166 }
167
169 if (predicates.isEmpty()){
170
171 throw new JoftiException("At least one predicate in where clause is required in Query");
174 }
175 Map results = processPredicates(predicates, query.getClassName(), nameSpace,query.getAliasMap(),index, query.getNamedValueMap());
177
178
179 return results;
180 }
181
182
183
184
185 protected Map processRemainder(Map results, FastStack predicates, Class className,Object nameSpace, Map aliasMap,TreeIndex index, Map namedParameters ) throws JoftiException{
186 while (predicates.size() %2 == 0 && predicates.size() != 0){
187 Operator op= (Operator)predicates.pop();
188 IPredicate second= (IPredicate) predicates.pop();
189 Map secondResults =null;
190 if (second.getType() ==1){
191 secondResults = processPredicates(((StackPredicate)second).getPredicateStack(), className, nameSpace, aliasMap,index,namedParameters);
192 }else{
193 secondResults = runPredicate(second, className, nameSpace,aliasMap,index, namedParameters);
194 }
195 results = resultJunction(results, op, secondResults);
196 }
197 return results;
198 }
199
200 protected Map runPredicate(IPredicate pred, Class className, Object nameSpace, Map aliasMap,TreeIndex index, Map namedParameters) throws JoftiException{
201 Class name =null;
202 Object tempAlias =null;
203 if (pred.getAlias() != null){
204 tempAlias =name = (Class )aliasMap.get(pred.getAlias());
205 }else{
206 name = className;
207 }
208 String attribute =null;
209 if (!(AttributeValueParser.VALUE.equalsIgnoreCase(pred.getField())) &&
210 (!index.getIntrospector().getPrimitiveClasses().contains(name.toString()))){
211 attribute = pred.getField();
212 }
213
214
215 try {
216
217 return performQuery(pred.getOperator(), name, nameSpace, attribute, pred.getValue(), index, namedParameters, tempAlias);
218 } catch (Throwable t){
219 if (t instanceof JoftiException){
220 throw (JoftiException)t;
221 }else{
222 throw new JoftiException(t);
223 }
224 }
225 }
226
227 protected Comparable wrapNull(Comparable value){
229 if (value == null){
230 return ValueObject.MIN_COMAPARBLE_VALUE;
231 }
232 return value;
233 }
234
235
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245
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248
249
250
251
252
253
254
255
256 protected void testNull(Object obj) throws JoftiException{
257 if (obj == null){
258 throw new JoftiException("value null not permitted in query");
259 }
260 }
261 protected abstract Map performQuery(int operator, Class className, Object nameSpace,String attribute, Object value, TreeIndex index, Map namedParameters, Object alias) throws JoftiException;
262
263 }
264 |
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