1 /*
2 * Copyright 2007 Kasper B. Graversen
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package org.supercsv.cellprocessor;
17
18 import java.text.SimpleDateFormat;
19 import java.util.Date;
20
21 import org.supercsv.cellprocessor.ift.DateCellProcessor;
22 import org.supercsv.cellprocessor.ift.StringCellProcessor;
23 import org.supercsv.exception.SuperCsvCellProcessorException;
24 import org.supercsv.util.CsvContext;
25
26 /**
27 * Converts a date into a formatted string using the {@link SimpleDateFormat} class. If you want to convert from a
28 * String to a Date, use the {@link ParseDate} processor.
29 * <p>
30 * Some example date formats you can use are:<br>
31 * <code>"dd/MM/yyyy"</code> (formats a date as "25/12/2011")<br>
32 * <code>"dd-MMM-yy"</code> (formats a date as "25-Dec-11")<br>
33 * <code>"yyyy.MM.dd.HH.mm.ss"</code> (formats a date as "2011.12.25.08.36.33"<br>
34 * <code>"E, dd MMM yyyy HH:mm:ss Z"</code> (formats a date as "Tue, 25 Dec 2011 08:36:33 -0500")<br>
35 *
36 * @since 1.50
37 * @author Dominique De Vito
38 * @author James Bassett
39 */
40 public class FmtDate extends CellProcessorAdaptor implements DateCellProcessor {
41
42 private final String dateFormat;
43
44 /**
45 * Constructs a new <tt>FmtDate</tt> processor, which converts a date into a formatted string using
46 * SimpleDateFormat.
47 *
48 * @param dateFormat
49 * the date format String (see {@link SimpleDateFormat})
50 * @throws NullPointerException
51 * if dateFormat is null
52 */
53 public FmtDate(final String dateFormat) {
54 super();
55 checkPreconditions(dateFormat);
56 this.dateFormat = dateFormat;
57 }
58
59 /**
60 * Constructs a new <tt>FmtDate</tt> processor, which converts a date into a formatted string using
61 * SimpleDateFormat, then calls the next processor in the chain.
62 *
63 * @param dateFormat
64 * the date format String (see {@link SimpleDateFormat})
65 * @param next
66 * the next processor in the chain
67 * @throws NullPointerException
68 * if dateFormat or next is null
69 */
70 public FmtDate(final String dateFormat, final StringCellProcessor next) {
71 super(next);
72 checkPreconditions(dateFormat);
73 this.dateFormat = dateFormat;
74 }
75
76 /**
77 * Checks the preconditions for creating a new FmtDate processor.
78 *
79 * @param dateFormat
80 * the date format String
81 * @throws NullPointerException
82 * if dateFormat is null
83 */
84 private static void checkPreconditions(final String dateFormat) {
85 if( dateFormat == null ) {
86 throw new NullPointerException("dateFormat should not be null");
87 }
88 }
89
90 /**
91 * {@inheritDoc}
92 *
93 * @throws SuperCsvCellProcessorException
94 * if value is null or is not a Date, or if dateFormat is not a valid date format
95 */
96 public Object execute(final Object value, final CsvContext context) {
97 validateInputNotNull(value, context);
98
99 if( !(value instanceof Date) ) {
100 throw new SuperCsvCellProcessorException(Date.class, value, context, this);
101 }
102
103 final SimpleDateFormat formatter;
104 try {
105 formatter = new SimpleDateFormat(dateFormat);
106 }
107 catch(IllegalArgumentException e) {
108 throw new SuperCsvCellProcessorException(String.format("'%s' is not a valid date format", dateFormat),
109 context, this, e);
110 }
111
112 String result = formatter.format((Date) value);
113 return next.execute(result, context);
114 }
115 }