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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.Level ;
37 import java.util.logging.Logger ;
38 import java.util.regex.Pattern ;
39
40 class LikeExpr extends Expr {
41 private static final Logger log = Log.open(LikeExpr.class);
42
43 private Expr _expr;
44 private String _pattern;
45 private Pattern _regexp;
46 private boolean _isNot;
47
48 LikeExpr(Expr expr, String pattern, boolean isNot)
49 {
50 _expr = expr;
51 _pattern = pattern;
52 _isNot = isNot;
53
54 StringBuilder sb = new StringBuilder ();
55 for (int i = 0; i < pattern.length(); i++) {
56 char ch = pattern.charAt(i);
57
58 switch (ch) {
59 case '%':
60 sb.append(".*");
61 break;
62 case '_':
63 sb.append(".");
64 break;
65 case '.': case '\\': case '*': case '+': case '(': case ')':
66 case '[': case ']': case '?': case '^': case '$': case '|':
67 sb.append("\\");
68 sb.append(ch);
69 break;
70 default:
71 sb.append(ch);
72 }
73 }
74
75 try {
76 _regexp = Pattern.compile(sb.toString());
77 } catch (Exception e) {
78 log.log(Level.WARNING, e.toString(), e);
79 }
80 }
81
82 protected Expr bind(Query query)
83 throws SQLException
84 {
85 _expr = _expr.bind(query);
86
87 return this;
88 }
89
90
93 public Class getType()
94 {
95 return boolean.class;
96 }
97
98
101 public long subCost(ArrayList <FromItem> fromList)
102 {
103 return (_expr.subCost(fromList));
104 }
105
106
109 public int evalBoolean(QueryContext context)
110 throws SQLException
111 {
112 if (_expr.isNull(context))
113 return UNKNOWN;
114
115 String value = _expr.evalString(context);
116
117 if (_regexp.matcher(value).matches())
118 return _isNot ? FALSE : TRUE;
119 else
120 return _isNot ? TRUE : FALSE;
121 }
122
123 public String evalString(QueryContext context)
124 throws SQLException
125 {
126 throw new SQLException ("can't convert string to boolean");
127 }
128
129
134 public void evalGroup(QueryContext context)
135 throws SQLException
136 {
137 _expr.evalGroup(context);
138 }
139
140 public String toString()
141 {
142 return "(" + _expr + " LIKE " + _pattern + ")";
143 }
144 }
145 |
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