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1   /*
2    * $Id: AbstractCellRenderer.java 471756 2006-11-06 15:01:43Z husted $
3    *
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *  http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  package org.apache.struts2.components.table.renderer;
22  
23  import org.apache.struts2.components.table.WebTable;
24  
25  
26  /***
27   * this is the base class that most renderers will be derived from.
28   * It allows setting the alignment.  Subclasses should set there actuall
29   * content by implementing getCellValue
30   */
31  abstract public class AbstractCellRenderer implements CellRenderer {
32  
33      /***
34       * used for horizontal cell alignmnet
35       */
36      protected String _alignment = null;
37  
38  
39      public void setAlignment(String alignment) {
40          _alignment = alignment;
41      }
42  
43      public String getAlignment() {
44          return _alignment;
45      }
46  
47      /***
48       * implememnts CellRenderer renderCell.  It sets the alignment.  gets the actual
49       * data from getCellValue
50       */
51      public String renderCell(WebTable table, Object data, int row, int col) {
52          if (isAligned()) {
53              StringBuffer buf = new StringBuffer(256);
54              buf.append("<div align='").append(_alignment).append("'>");
55              buf.append(getCellValue(table, data, row, col));
56              buf.append("</div>");
57  
58              return buf.toString();
59          }
60  
61          return getCellValue(table, data, row, col);
62      }
63  
64      protected boolean isAligned() {
65          return _alignment != null;
66      }
67  
68      /***
69       * this is the method that subclasses need to implement to set their value.
70       * they should not override renderCell unless they want to change the alignmnent
71       * renderering
72       */
73      abstract protected String getCellValue(WebTable table, Object data, int row, int col);
74  }