StringVector2VarcharFieldConversion


1   package org.apache.ojb.broker.accesslayer.conversions;
2   
3   /* Copyright 2002-2005 The Apache Software Foundation
4    *
5    * Licensed under the Apache License, Version 2.0 (the "License");
6    * you may not use this file except in compliance with the License.
7    * You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  import java.util.Vector  ;
19  
20  /**
21   * Converts a Vector of string elements back and forth from a database varchar field
22   * Strings may not contain "#" as this is used as separator.
23   * This class maybe useful if it's important to have the string vector stored in a 
24   * human readable form that allows editing.
25   * @see Object2ByteArrFieldConversion uses Java serialization and is not suited for
26   * this purpose. 
27   * 
28   * @author  sschloesser  mailto: stefan.schl@gmx.de 
29   * @version $Id: StringVector2VarcharFieldConversion.java,v 1.6.2.2 2005/12/21 22:23:38 tomdz Exp $
30   */
31  public class StringVector2VarcharFieldConversion implements FieldConversion
32  {
33  
34      private static final String   NULLVALUE = "#NULL#";
35      private static final String   EMPTYCOLLEC = "#EMTPY#";
36      private static final String   SEPARATOR = "#";
37  
38      /** Creates a new instance of StringVector2VarcharFieldConversion */
39      public StringVector2VarcharFieldConversion()
40      {
41      }
42  
43      public Object   javaToSql(Object   obj)
44          throws org.apache.ojb.broker.accesslayer.conversions.ConversionException
45      {
46  
47          if (obj == null)
48          {
49              return NULLVALUE;
50          }
51  
52          if (!(obj instanceof Vector  ))
53          {
54              throw new ConversionException(
55                  "Object is not a vector it is a" + obj.getClass().getName());
56          }
57  
58          Vector   v = (Vector  ) obj;
59          if (v.size() == 0)
60          {
61              return EMPTYCOLLEC;
62          }
63  
64          StringBuffer   result = new StringBuffer  ();
65          for (int i = 0; i < v.size(); i++)
66          {
67              String   newSt = v.get(i).toString();
68              if (newSt.indexOf(SEPARATOR) >= 0)
69              {
70                  throw new ConversionException(
71                      "An entry in the Vector contains the forbidden "
72                          + SEPARATOR
73                          + " character used to separate the strings on the DB");
74              }
75              result.append(newSt);
76              result.append(SEPARATOR);
77          }
78          return result.toString();
79      }
80  
81      public Object   sqlToJava(Object   obj)
82          throws org.apache.ojb.broker.accesslayer.conversions.ConversionException
83      {
84  
85          if (obj == null)
86          {
87              return null;
88          }
89          if (obj.toString().equals(NULLVALUE))
90          {
91              return null;
92          }
93          if (obj.toString().equals(EMPTYCOLLEC))
94          {
95              return new Vector  ();
96          }
97  
98          Vector   v = new Vector  ();
99          String   input = obj.toString();
100         int pos = input.indexOf(SEPARATOR);
101 
102         while (pos >= 0)
103         {
104             if (pos == 0)
105             {
106                 v.add("");
107             }
108             else
109             {
110                 v.add(input.substring(0, pos));
111             }
112 
113             if (pos + 1 > input.length()) //# at end causes outof bounds
114             {
115                 break;
116             }
117 
118             input = input.substring(pos + 1, input.length());
119             pos = input.indexOf(SEPARATOR);
120         }
121         return v;
122     }
123 }
124
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Free Books Free Magazines
Popular Tags