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 * https://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.validator.routines;
18
19 import java.text.DecimalFormat;
20 import java.text.Format;
21
22 /**
23 * <p><strong>Currency Validation</strong> and Conversion routines ({@code java.math.BigDecimal}).</p>
24 *
25 * <p>This is one implementation of a currency validator that has the following features:</p>
26 * <ul>
27 * <li>It is <em>lenient</em> about the presence of the <em>currency symbol</em></li>
28 * <li>It converts the currency to a {@code java.math.BigDecimal}</li>
29 * </ul>
30 *
31 * <p>However any of the <em>number</em> validators can be used for <em>currency</em> validation.
32 * For example, if you wanted a <em>currency</em> validator that converts to a
33 * {@link Integer} then you can simply instantiate an
34 * {@code IntegerValidator} with the appropriate <em>format type</em>:</p>
35 *
36 * <p>{@code ... = new IntegerValidator(false, IntegerValidator.CURRENCY_FORMAT);}</p>
37 *
38 * <p>Pick the appropriate validator, depending on the type (for example, Float, Double, Integer, Long and so on)
39 * you want the currency converted to. One thing to note - only the CurrencyValidator
40 * implements <em>lenient</em> behavior regarding the currency symbol.</p>
41 *
42 * @since 1.3.0
43 */
44 public class CurrencyValidator extends BigDecimalValidator {
45
46 private static final long serialVersionUID = -4201640771171486514L;
47
48 private static final CurrencyValidator VALIDATOR = new CurrencyValidator();
49
50 /** DecimalFormat's currency symbol */
51 private static final char CURRENCY_SYMBOL = '\u00A4';
52
53 /**
54 * Gets the singleton instance of this validator.
55 *
56 * @return A singleton instance of the CurrencyValidator.
57 */
58 public static BigDecimalValidator getInstance() {
59 return VALIDATOR;
60 }
61
62 /**
63 * Constructs a <em>strict</em> instance.
64 */
65 public CurrencyValidator() {
66 this(true, true);
67 }
68
69 /**
70 * Constructs an instance with the specified strict setting.
71 *
72 * @param strict {@code true} if strict
73 * {@code Format} parsing should be used.
74 * @param allowFractions {@code true} if fractions are
75 * allowed or {@code false} if integers only.
76 */
77 public CurrencyValidator(final boolean strict, final boolean allowFractions) {
78 super(strict, CURRENCY_FORMAT, allowFractions);
79 }
80
81 /**
82 * <p>Parse the value with the specified {@code Format}.</p>
83 *
84 * <p>This implementation is lenient whether the currency symbol
85 * is present or not. The default {@code NumberFormat}
86 * behavior is for the parsing to "fail" if the currency
87 * symbol is missing. This method re-parses with a format
88 * without the currency symbol if it fails initially.</p>
89 *
90 * @param value The value to be parsed.
91 * @param formatter The Format to parse the value with.
92 * @return The parsed value if valid or {@code null} if invalid.
93 */
94 @Override
95 protected Object parse(final String value, final Format formatter) {
96
97 // Initial parse of the value
98 Object parsedValue = super.parse(value, formatter);
99 if (parsedValue != null || !(formatter instanceof DecimalFormat)) {
100 return parsedValue;
101 }
102
103 // Re-parse using a pattern without the currency symbol
104 final DecimalFormat decimalFormat = (DecimalFormat) formatter;
105 final String pattern = decimalFormat.toPattern();
106 if (pattern.indexOf(CURRENCY_SYMBOL) >= 0) {
107 final StringBuilder buffer = new StringBuilder(pattern.length());
108 for (int i = 0; i < pattern.length(); i++) {
109 if (pattern.charAt(i) != CURRENCY_SYMBOL) {
110 buffer.append(pattern.charAt(i));
111 }
112 }
113 decimalFormat.applyPattern(buffer.toString());
114 parsedValue = super.parse(value, decimalFormat);
115 }
116 return parsedValue;
117 }
118 }