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1
28
29 package com.caucho.db.sql;
30
31 import com.caucho.log.Log;
32
33 import java.sql.SQLException  ;
34 import java.util.ArrayList ;
35 import java.util.logging.Logger ;
36
37 class DoubleCmpExpr extends Expr {
38 private static final Logger log = Log.open(DoubleCmpExpr.class);
39
40 private Expr _left;
41 private Expr _right;
42 private int _op;
43
44 DoubleCmpExpr(int op, Expr left, Expr right)
45 {
46 _left = left;
47 _right = right;
48 _op = op;
49 }
50
51 protected Expr bind(Query query)
52 throws SQLException
53 {
54 Expr newLeft = _left.bind(query);
55 Expr newRight = _right.bind(query);
56
57 if (_left == newLeft && _right == newRight)
58 return this;
59 else
60 return new CmpExpr(newLeft, newRight, _op);
61 }
62
63
66 public Class getType()
67 {
68 return boolean.class;
69 }
70
71
74 public long subCost(ArrayList <FromItem> fromList)
75 {
76 return _left.subCost(fromList) + _right.subCost(fromList);
77 }
78
79
82 public int evalBoolean(QueryContext context)
83 throws SQLException
84 {
85 if (_left.isNull(context) || _right.isNull(context))
86 return UNKNOWN;
87
88 switch (_op) {
89 case Parser.LT:
90 if (_left.evalDouble(context) < _right.evalDouble(context))
91 return TRUE;
92 else
93 return FALSE;
94
95 case Parser.LE:
96 if (_left.evalDouble(context) <= _right.evalDouble(context))
97 return TRUE;
98 else
99 return FALSE;
100
101 case Parser.GT:
102 if (_left.evalDouble(context) > _right.evalDouble(context))
103 return TRUE;
104 else
105 return FALSE;
106
107 case Parser.GE:
108 if (_left.evalDouble(context) >= _right.evalDouble(context))
109 return TRUE;
110 else
111 return FALSE;
112
113 case Parser.NE:
114 if (_left.evalDouble(context) != _right.evalDouble(context))
115 return TRUE;
116 else
117 return FALSE;
118
119 case Parser.EQ:
120 if (_left.evalDouble(context) == _right.evalDouble(context))
121 return TRUE;
122 else
123 return FALSE;
124
125 default:
126 throw new SQLException ("can't compare");
127 }
128 }
129
130 public String evalString(QueryContext context)
131 throws SQLException
132 {
133 throw new SQLException ("can't convert string to boolean");
134 }
135
136
141 public void evalGroup(QueryContext context)
142 throws SQLException
143 {
144 _left.evalGroup(context);
145 _right.evalGroup(context);
146 }
147
148 public String toString()
149 {
150 return "(" + _left + " = " + _right + ")";
151 }
152 }
153 |
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