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/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.commons.validator.routines; import java.io.Serializable; import java.text.Format; import java.text.ParsePosition; import java.util.Locale; /** * <p> * Abstract class for <i>Format</i> based Validation. * </p> * * <p> * This is a <i>base</i> class for building Date and Number Validators using format parsing. * </p> * * @version $Revision: 594917 $ $Date: 2007-11-14 15:36:40 +0000 (Qua, 14 Nov 2007) $ * @since Validator 1.3.0 */ public abstract class AbstractFormatValidator implements Serializable { private final boolean strict; /** * Construct an instance with the specified strict setting. * * @param strict <code>true</code> if strict <code>Format</code> parsing should be used. */ public AbstractFormatValidator(boolean strict) { this.strict = strict; } /** * <p> * Indicates whether validated values should adhere strictly to the <code>Format</code> used. * </p> * * <p> * Typically implementations of <code>Format</code> ignore invalid characters at the end of the value and just stop parsing. * For example parsing a date value of <code>01/01/20x0</code> using a pattern of <code>dd/MM/yyyy</code> will result in a * year of <code>20</code> if <code>strict</code> is set to <code>false</code>, whereas setting <code>strict</code> to * <code>true</code> will cause this value to fail validation. * </p> * * @return <code>true</code> if strict <code>Format</code> parsing should be used. */ public boolean isStrict() { return strict; } /** * <p> * Validate using the default <code>Locale</code>. * * @param value The value validation is being performed on. * @return <code>true</code> if the value is valid. */ public boolean isValid(String value) { return isValid(value, (String) null, (Locale) null); } /** * <p> * Validate using the specified <i>pattern</i>. * * @param value The value validation is being performed on. * @param pattern The pattern used to validate the value against. * @return <code>true</code> if the value is valid. */ public boolean isValid(String value, String pattern) { return isValid(value, pattern, (Locale) null); } /** * <p> * Validate using the specified <code>Locale</code>. * * @param value The value validation is being performed on. * @param locale The locale to use for the Format, defaults to the default * @return <code>true</code> if the value is valid. */ public boolean isValid(String value, Locale locale) { return isValid(value, (String) null, locale); } /** * <p> * Validate using the specified pattern and/or <code>Locale</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to format the value. * @param locale The locale to use for the Format, defaults to the default * @return <code>true</code> if the value is valid. */ public abstract boolean isValid(String value, String pattern, Locale locale); /** * <p> * Format an object into a <code>String</code> using the default Locale. * </p> * * @param value The value validation is being performed on. * @return The value formatted as a <code>String</code>. */ public String format(Object value) { return format(value, (String) null, (Locale) null); } /** * <p> * Format an object into a <code>String</code> using the specified pattern. * </p> * * @param value The value validation is being performed on. * @param pattern The pattern used to format the value. * @return The value formatted as a <code>String</code>. */ public String format(Object value, String pattern) { return format(value, pattern, (Locale) null); } /** * <p> * Format an object into a <code>String</code> using the specified Locale. * </p> * * @param value The value validation is being performed on. * @param locale The locale to use for the Format. * @return The value formatted as a <code>String</code>. */ public String format(Object value, Locale locale) { return format(value, (String) null, locale); } /** * <p> * Format an object using the specified pattern and/or <code>Locale</code>. * * @param value The value validation is being performed on. * @param pattern The pattern used to format the value. * @param locale The locale to use for the Format. * @return The value formatted as a <code>String</code>. */ public String format(Object value, String pattern, Locale locale) { Format formatter = getFormat(pattern, locale); return format(value, formatter); } /** * <p> * Format a value with the specified <code>Format</code>. * </p> * * @param value The value to be formatted. * @param formatter The Format to use. * @return The formatted value. */ protected String format(Object value, Format formatter) { return formatter.format(value); } /** * <p> * Parse the value with the specified <code>Format</code>. * </p> * * @param value The value to be parsed. * @param formatter The Format to parse the value with. * @return The parsed value if valid or <code>null</code> if invalid. */ protected Object parse(String value, Format formatter) { ParsePosition pos = new ParsePosition(0); Object parsedValue = formatter.parseObject(value, pos); if (pos.getErrorIndex() > -1) { return null; } if (isStrict() && pos.getIndex() < value.length()) { return null; } if (parsedValue != null) { parsedValue = processParsedValue(parsedValue, formatter); } return parsedValue; } /** * <p> * Process the parsed value, performing any further validation and type conversion required. * </p> * * @param value The parsed object created. * @param formatter The Format used to parse the value with. * @return The parsed value converted to the appropriate type * if valid or <code>null</code> if invalid. */ protected abstract Object processParsedValue(Object value, Format formatter); /** * <p> * Returns a <code>Format</code> for the specified <i>pattern</i> and/or <code>Locale</code>. * </p> * * @param pattern The pattern used to validate the value against or <code>null</code> to use the default for the * <code>Locale</code>. * @param locale The locale to use for the currency format, system default if null. * @return The <code>NumberFormat</code> to created. */ protected abstract Format getFormat(String pattern, Locale locale); }