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Java > Open Source Codes > com > caucho > db > sql > LongExpr


1 /*
2  * Copyright (c) 1998-2006 Caucho Technology -- all rights reserved
3  *
4  * This file is part of Resin(R) Open Source
5  *
6  * Each copy or derived work must preserve the copyright notice and this
7  * notice unmodified.
8  *
9  * Resin Open Source is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * Resin Open Source is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
17  * of NON-INFRINGEMENT. See the GNU General Public License for more
18  * details.
19  *
20  * You should have received a copy of the GNU General Public License
21  * along with Resin Open Source; if not, write to the
22  * Free SoftwareFoundation, Inc.
23  * 59 Temple Place, Suite 330
24  * Boston, MA 02111-1307 USA
25  *
26  * @author Scott Ferguson
27  */
28
29 package com.caucho.db.sql;
30
31 import com.caucho.log.Log;
32
33 import java.sql.SQLException JavaDoc;
34 import java.util.ArrayList JavaDoc;
35 import java.util.logging.Logger JavaDoc;
36
37 class LongExpr extends Expr {
38   private static final Logger JavaDoc log = Log.open(LongExpr.class);
39
40   private long _value;
41
42   LongExpr(long value)
43   {
44     _value = value;
45   }
46
47   /**
48    * Returns the type of the expression.
49    */
50   public Class JavaDoc getType()
51   {
52     return long.class;
53   }
54
55   /**
56    * Returns the cost based on the given FromList.
57    */
58   public long subCost(ArrayList JavaDoc<FromItem> fromList)
59   {
60     return 0;
61   }
62
63   /**
64    * Evaluates the expression as a long
65    *
66    * @param row the current data tuple
67    *
68    * @return the long value
69    */
70   public long evalLong(QueryContext context)
71     throws SQLException JavaDoc
72   {
73     return _value;
74   }
75
76   /**
77    * Evaluates the expression as a date
78    *
79    * @param row the current data tuple
80    *
81    * @return the date value
82    */
83   public long evalDate(QueryContext context)
84     throws SQLException JavaDoc
85   {
86     return _value;
87   }
88
89   /**
90    * Evaluates the expression as a double
91    *
92    * @param row the current data tuple
93    *
94    * @return the double value
95    */
96   public double evalDouble(QueryContext context)
97     throws SQLException JavaDoc
98   {
99     return _value;
100   }
101
102   /**
103    * Evaluates the expression as a string
104    *
105    * @param row the current data tuple
106    *
107    * @return the string value
108    */
109   public String JavaDoc evalString(QueryContext context)
110     throws SQLException JavaDoc
111   {
112     return String.valueOf(_value);
113   }
114
115   /**
116    * Evaluates the expression, writing to the result stream.
117    *
118    * @param context the query context
119    * @param result the output result
120    */
121   public void evalToResult(QueryContext context, SelectResult result)
122   {
123     result.writeLong(_value);
124   }
125
126   public String JavaDoc toString()
127   {
128     return String.valueOf(_value);
129   }
130 }
131
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