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1
29
30 package com.caucho.db.sql;
31
32 import com.caucho.log.Log;
33
34 import java.sql.SQLException  ;
35 import java.util.ArrayList ;
36 import java.util.logging.Logger ;
37
38 class CmpExpr extends Expr {
39 private static final Logger log = Log.open(CmpExpr.class);
40
41 private Expr _left;
42 private Expr _right;
43 private int _op;
44
45 CmpExpr(Expr left, Expr right, int op)
46 {
47 _left = left;
48 _right = right;
49 _op = op;
50 }
51
52 protected Expr bind(Query query)
53 throws SQLException
54 {
55 _left = _left.bind(query);
56 _right = _right.bind(query);
57
58 switch (_op) {
59 case Parser.LT:
60 case Parser.LE:
61 case Parser.GT:
62 case Parser.GE:
63 return new DoubleCmpExpr(_op, _left, _right);
64 }
65
66 if (_left.isDouble() || _right.isDouble())
67 return new DoubleCmpExpr(_op, _left, _right);
68
69 return this;
70 }
71
72
75 public Class getType()
76 {
77 return boolean.class;
78 }
79
80
83 public long subCost(ArrayList <FromItem> fromList)
84 {
85 return _left.subCost(fromList) + _right.subCost(fromList);
86 }
87
88
91 public int evalBoolean(QueryContext context)
92 throws SQLException
93 {
94 if (_left.isNull(context) || _right.isNull(context))
95 return UNKNOWN;
96
97 switch (_op) {
98 case Parser.NE:
99 {
100 String leftValue = _left.evalString(context);
101 String rightValue = _right.evalString(context);
102
103 if (! (leftValue == rightValue ||
104 leftValue != null && leftValue.equals(rightValue)))
105 return TRUE;
106 else
107 return FALSE;
108 }
109
110 case Parser.EQ:
111 {
112 String leftValue = _left.evalString(context);
113 String rightValue = _right.evalString(context);
114
115 if (leftValue == rightValue ||
116 leftValue != null && leftValue.equals(rightValue))
117 return TRUE;
118 else
119 return FALSE;
120 }
121
122 default:
123 throw new SQLException ("can't compare");
124 }
125 }
126
127 public String evalString(QueryContext context)
128 throws SQLException
129 {
130 throw new SQLException ("can't convert string to boolean");
131 }
132
133
138 public void evalGroup(QueryContext context)
139 throws SQLException
140 {
141 _left.evalGroup(context);
142 _right.evalGroup(context);
143 }
144
145 public String toString()
146 {
147 switch (_op) {
148 case Parser.EQ:
149 return "(" + _left + " = " + _right + ")";
150 case Parser.NE:
151 return "(" + _left + " <> " + _right + ")";
152 case Parser.LT:
153 return "(" + _left + " < " + _right + ")";
154 case Parser.LE:
155 return "(" + _left + " <= " + _right + ")";
156 case Parser.GT:
157 return "(" + _left + " > " + _right + ")";
158 case Parser.GE:
159 return "(" + _left + " >= " + _right + ")";
160 default:
161 return "(" + _left + " =? " + _right + ")";
162 }
163 }
164 }
165 |
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