001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.commons.validator.routines; 018 019import java.text.DecimalFormat; 020import java.text.Format; 021 022/** 023 * <p><b>Currency Validation</b> and Conversion routines (<code>java.math.BigDecimal</code>).</p> 024 * 025 * <p>This is one implementation of a currency validator that has the following features:</p> 026 * <ul> 027 * <li>It is <i>lenient</i> about the presence of the <i>currency symbol</i></li> 028 * <li>It converts the currency to a <code>java.math.BigDecimal</code></li> 029 * </ul> 030 * 031 * <p>However any of the <i>number</i> validators can be used for <i>currency</i> validation. 032 * For example, if you wanted a <i>currency</i> validator that converts to a 033 * <code>java.lang.Integer</code> then you can simply instantiate an 034 * <code>IntegerValidator</code> with the appropriate <i>format type</i>:</p> 035 * 036 * <p><code>... = new IntegerValidator(false, IntegerValidator.CURRENCY_FORMAT);</code></p> 037 * 038 * <p>Pick the appropriate validator, depending on the type (e.g Float, Double, Integer, Long etc) 039 * you want the currency converted to. One thing to note - only the CurrencyValidator 040 * implements <i>lenient</i> behavior regarding the currency symbol.</p> 041 * 042 * @version $Revision$ 043 * @since Validator 1.3.0 044 */ 045public class CurrencyValidator extends BigDecimalValidator { 046 047 private static final long serialVersionUID = -4201640771171486514L; 048 049 private static final CurrencyValidator VALIDATOR = new CurrencyValidator(); 050 051 /** DecimalFormat's currency symbol */ 052 private static final char CURRENCY_SYMBOL = '\u00A4'; 053 054 /** 055 * Return a singleton instance of this validator. 056 * @return A singleton instance of the CurrencyValidator. 057 */ 058 public static BigDecimalValidator getInstance() { 059 return VALIDATOR; 060 } 061 062 /** 063 * Construct a <i>strict</i> instance. 064 */ 065 public CurrencyValidator() { 066 this(true, true); 067 } 068 069 /** 070 * Construct an instance with the specified strict setting. 071 * 072 * @param strict <code>true</code> if strict 073 * <code>Format</code> parsing should be used. 074 * @param allowFractions <code>true</code> if fractions are 075 * allowed or <code>false</code> if integers only. 076 */ 077 public CurrencyValidator(boolean strict, boolean allowFractions) { 078 super(strict, CURRENCY_FORMAT, allowFractions); 079 } 080 081 /** 082 * <p>Parse the value with the specified <code>Format</code>.</p> 083 * 084 * <p>This implementation is lenient whether the currency symbol 085 * is present or not. The default <code>NumberFormat</code> 086 * behavior is for the parsing to "fail" if the currency 087 * symbol is missing. This method re-parses with a format 088 * without the currency symbol if it fails initially.</p> 089 * 090 * @param value The value to be parsed. 091 * @param formatter The Format to parse the value with. 092 * @return The parsed value if valid or <code>null</code> if invalid. 093 */ 094 @Override 095 protected Object parse(String value, Format formatter) { 096 097 // Initial parse of the value 098 Object parsedValue = super.parse(value, formatter); 099 if (parsedValue != null || !(formatter instanceof DecimalFormat)) { 100 return parsedValue; 101 } 102 103 // Re-parse using a pattern without the currency symbol 104 DecimalFormat decimalFormat = (DecimalFormat)formatter; 105 String pattern = decimalFormat.toPattern(); 106 if (pattern.indexOf(CURRENCY_SYMBOL) >= 0) { 107 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}