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.constraint;
17
18 import org.supercsv.cellprocessor.CellProcessorAdaptor;
19 import org.supercsv.cellprocessor.ift.CellProcessor;
20 import org.supercsv.cellprocessor.ift.StringCellProcessor;
21 import org.supercsv.exception.SuperCsvCellProcessorException;
22 import org.supercsv.exception.SuperCsvConstraintViolationException;
23 import org.supercsv.util.CsvContext;
24
25 /**
26 * This processor checks if the input is <tt>null</tt> or an empty string, and raises an exception in that case. In all
27 * other cases, the next processor in the chain is invoked.
28 * <p>
29 * You should only use this processor, when a column must be non-null, but you do not need to apply any other processor
30 * to the column.
31 * <p>
32 * If you apply other processors to the column, you can safely omit this processor as all other processors should do a
33 * null-check on its input.
34 *
35 * @since 1.50
36 * @author Dominique De Vito
37 */
38 public class StrNotNullOrEmpty extends CellProcessorAdaptor implements StringCellProcessor {
39
40 /**
41 * Constructs a new <tt>StrNotNullOrEmpty</tt> processor, which checks for null/empty Strings.
42 */
43 public StrNotNullOrEmpty() {
44 super();
45 }
46
47 /**
48 * Constructs a new <tt>StrNotNullOrEmpty</tt> processor, which checks for null/empty Strings, then calls the next
49 * processor in the chain.
50 *
51 * @param next
52 * the next processor in the chain
53 * @throws NullPointerException
54 * if next is null
55 */
56 public StrNotNullOrEmpty(final CellProcessor next) {
57 super(next);
58 }
59
60 /**
61 * {@inheritDoc}
62 *
63 * @throws SuperCsvCellProcessorException
64 * if value is null or isn't a String
65 * @throws SuperCsvConstraintViolationException
66 * if value is an empty String
67 */
68 public Object execute(final Object value, final CsvContext context) {
69 if (value == null){
70 throw new SuperCsvConstraintViolationException("the String should not be null", context, this);
71 }
72
73 if( value instanceof String ) {
74 final String stringValue = (String) value;
75 if( stringValue.length() == 0 ) {
76 throw new SuperCsvConstraintViolationException("the String should not be empty", context, this);
77 }
78 } else {
79 throw new SuperCsvCellProcessorException(String.class, value, context, this);
80 }
81
82 return next.execute(value, context);
83 }
84 }