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1
5 package org.h2.expression;
6
7 import java.sql.SQLException  ;
8
9 import org.h2.engine.Constants;
10 import org.h2.engine.Session;
11 import org.h2.message.Message;
12 import org.h2.table.ColumnResolver;
13 import org.h2.table.TableFilter;
14 import org.h2.value.Value;
15 import org.h2.value.ValueBoolean;
16 import org.h2.value.ValueNull;
17
18
21 public class ConditionAndOr extends Condition {
22 public static final int AND = 0, OR = 1;
24 private int andOrType;
25 private Expression left, right;
26
27 public ConditionAndOr(int andOrType, Expression left, Expression right) {
28 this.andOrType = andOrType;
29 this.left = left;
30 this.right = right;
31 if(Constants.CHECK && (left == null || right == null)) {
32 throw Message.getInternalError();
33 }
34 }
35
36 public String getSQL() {
37 String sql;
38 switch(andOrType) {
39 case AND:
40 sql = left.getSQL() + " AND " + right.getSQL();
41 break;
42 case OR:
43 sql = left.getSQL() + " OR " + right.getSQL();
44 break;
45 default:
46 throw Message.getInternalError("andOrType="+andOrType);
47 }
48 return "("+sql+")";
49 }
50
51 public void createIndexConditions(TableFilter filter) throws SQLException {
52 if (andOrType == AND) {
53 left.createIndexConditions(filter);
54 right.createIndexConditions(filter);
55 }
56 }
57
58 public Value getValue(Session session) throws SQLException {
59 Value l = left.getValue(session);
60 Value r;
61 switch (andOrType) {
62 case AND: {
63 if (Boolean.FALSE.equals(l.getBoolean())) {
64 return l;
65 }
66 r = right.getValue(session);
67 if (Boolean.FALSE.equals(r.getBoolean())) {
68 return r;
69 }
70 if(l == ValueNull.INSTANCE) {
71 return l;
72 }
73 if(r == ValueNull.INSTANCE) {
74 return r;
75 }
76 return ValueBoolean.get(true);
77 }
78 case OR: {
79 if (Boolean.TRUE.equals(l.getBoolean())) {
80 return l;
81 }
82 r = right.getValue(session);
83 if (Boolean.TRUE.equals(r.getBoolean())) {
84 return r;
85 }
86 if(l == ValueNull.INSTANCE) {
87 return l;
88 }
89 if(r == ValueNull.INSTANCE) {
90 return r;
91 }
92 return ValueBoolean.get(false);
93 }
94 default:
95 throw Message.getInternalError("type=" + andOrType);
96 }
97 }
98
99 public Expression optimize(Session session) throws SQLException {
100 left = left.optimize(session);
104 right = right.optimize(session);
105 int lc = left.getCost(), rc = right.getCost();
106 if(rc < lc) {
107 Expression t = left;
108 left = right;
109 right = t;
110 }
111 Value l = left.isConstant() ? left.getValue(session) : null;
112 Value r = right.isConstant() ? right.getValue(session) : null;
113 if(l==null && r==null) {
114 return this;
115 }
116 if(l != null && r != null) {
117 return ValueExpression.get(getValue(session));
118 }
119 switch (andOrType) {
120 case AND:
121 if(l != null) {
122 if(Boolean.FALSE.equals(l.getBoolean())) {
123 return ValueExpression.get(l);
124 } else if(Boolean.TRUE.equals(l.getBoolean())) {
125 return right;
126 }
127 } else if(r != null) {
128 if(Boolean.FALSE.equals(r.getBoolean())) {
129 return ValueExpression.get(r);
130 } else if(Boolean.TRUE.equals(r.getBoolean())) {
131 return left;
132 }
133 }
134 break;
135 case OR:
136 if(l != null) {
137 if(Boolean.TRUE.equals(l.getBoolean())) {
138 return ValueExpression.get(l);
139 } else if(Boolean.FALSE.equals(l.getBoolean())) {
140 return right;
141 }
142 } else if(r != null) {
143 if(Boolean.TRUE.equals(r.getBoolean())) {
144 return ValueExpression.get(r);
145 } else if(Boolean.FALSE.equals(r.getBoolean())) {
146 return left;
147 }
148 }
149 break;
150 default:
151 throw Message.getInternalError("type=" + andOrType);
152 }
153 return this;
154 }
155
156 public void addFilterConditions(TableFilter filter, boolean outerJoin) {
157 if (andOrType == AND) {
158 left.addFilterConditions(filter, outerJoin);
159 right.addFilterConditions(filter, outerJoin);
160 } else {
161 super.addFilterConditions(filter, outerJoin);
162 }
163 }
164
165 public void mapColumns(ColumnResolver resolver, int level) throws SQLException {
166 left.mapColumns(resolver, level);
167 right.mapColumns(resolver, level);
168 }
169
170 public void setEvaluatable(TableFilter tableFilter, boolean b) {
171 left.setEvaluatable(tableFilter, b);
172 right.setEvaluatable(tableFilter, b);
173 }
174
175 public void updateAggregate(Session session) throws SQLException {
176 left.updateAggregate(session);
177 right.updateAggregate(session);
178 }
179
180 public boolean isEverything(ExpressionVisitor visitor) {
181 return left.isEverything(visitor) && right.isEverything(visitor);
182 }
183
184 public int getCost() {
185 return left.getCost() + right.getCost();
186 }
187
188 }
189 |
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