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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  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  package org.apache.commons.lang.text;
18  
19  import java.text.FieldPosition;
20  import java.text.Format;
21  import java.text.ParseException;
22  import java.text.ParsePosition;
23  
24  /**
25   * Formats using one formatter and parses using a different formatter. An
26   * example of use for this would be a webapp where data is taken in one way and
27   * stored in a database another way.
28   * 
29   * @author Archimedes Trajano
30   * @version $Id: CompositeFormat.java 598710 2007-11-27 17:34:34Z mbenson $
31   */
32  public class CompositeFormat extends Format {
33  
34      /**
35       * Required for serialization support.
36       * 
37       * @see java.io.Serializable
38       */
39      private static final long serialVersionUID = -4329119827877627683L;
40  
41      /** The parser to use. */
42      private final Format parser;
43      /** The formatter to use. */
44      private final Format formatter;
45  
46      /**
47       * Create a format that points its parseObject method to one implementation
48       * and its format method to another.
49       * 
50       * @param parser implementation
51       * @param formatter implementation
52       */
53      public CompositeFormat(Format parser, Format formatter) {
54          this.parser = parser;
55          this.formatter = formatter;
56      }
57  
58      /**
59       * Uses the formatter Format instance.
60       * 
61       * @param obj the object to format
62       * @param toAppendTo the {@link StringBuffer} to append to
63       * @param pos the FieldPosition to use (or ignore).
64       * @return <code>toAppendTo</code>
65       * @see Format#format(Object, StringBuffer, FieldPosition)
66       */
67      public StringBuffer format(Object obj, StringBuffer toAppendTo,
68              FieldPosition pos) {
69          return formatter.format(obj, toAppendTo, pos);
70      }
71  
72      /**
73       * Uses the parser Format instance.
74       * 
75       * @param source the String source
76       * @param pos the ParsePosition containing the position to parse from, will
77       *            be updated according to parsing success (index) or failure
78       *            (error index)
79       * @return the parsed Object
80       * @see Format#parseObject(String, ParsePosition)
81       */
82      public Object parseObject(String source, ParsePosition pos) {
83          return parser.parseObject(source, pos);
84      }
85  
86      /**
87       * Provides access to the parser Format implementation.
88       * 
89       * @return parser Format implementation
90       */
91      public Format getParser() {
92          return this.parser;
93      }
94  
95      /**
96       * Provides access to the parser Format implementation.
97       * 
98       * @return formatter Format implementation
99       */
100     public Format getFormatter() {
101         return this.formatter;
102     }
103 
104     /**
105      * Utility method to parse and then reformat a String.
106      * 
107      * @param input String to reformat
108      * @return A reformatted String
109      * @throws ParseException thrown by parseObject(String) call
110      */
111     public String reformat(String input) throws ParseException {
112         return format(parseObject(input));
113     }
114 
115 }