001    // Copyright 2005 The Apache Software Foundation
002    //
003    // Licensed under the Apache License, Version 2.0 (the "License");
004    // you may not use this file except in compliance with the License.
005    // You may obtain a copy of the License at
006    //
007    //     http://www.apache.org/licenses/LICENSE-2.0
008    //
009    // Unless required by applicable law or agreed to in writing, software
010    // distributed under the License is distributed on an "AS IS" BASIS,
011    // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012    // See the License for the specific language governing permissions and
013    // limitations under the License.
014    
015    package org.apache.tapestry.form.translator;
016    
017    import org.apache.hivemind.HiveMind;
018    import org.apache.hivemind.util.PropertyUtils;
019    import org.apache.tapestry.form.IFormComponent;
020    import org.apache.tapestry.form.ValidationMessages;
021    import org.apache.tapestry.valid.ValidationConstraint;
022    import org.apache.tapestry.valid.ValidatorException;
023    
024    import java.text.Format;
025    import java.text.ParseException;
026    import java.util.Locale;
027    
028    /**
029     * Abstract {@link Translator} implementation for {@link java.text.Format}-based translators.
030     * 
031     * @author Paul Ferraro
032     * @since 4.0
033     */
034    public abstract class FormatTranslator extends AbstractTranslator
035    {
036        private String _pattern;
037    
038        public FormatTranslator()
039        {
040            _pattern = defaultPattern();
041        }
042    
043        //TODO: Needed until HIVEMIND-134 fix is available
044        public FormatTranslator(String initializer)
045        {
046            PropertyUtils.configureProperties(this, initializer);
047            
048            if (HiveMind.isBlank(_pattern))
049            {
050                _pattern = defaultPattern();
051            }
052        }
053        
054        protected abstract String defaultPattern();
055    
056        /**
057         * @see org.apache.tapestry.form.translator.AbstractTranslator#formatObject(org.apache.tapestry.form.IFormComponent,
058         *      Locale, java.lang.Object)
059         */
060        protected String formatObject(IFormComponent field, Locale locale, Object object)
061        {
062            // Get a new format each time, because (a) have to account for locale and (b) formatters are
063            // not thread safe.
064    
065            Format format = getFormat(locale);
066    
067            return format.format(object);
068        }
069    
070        /**
071         * @see org.apache.tapestry.form.translator.AbstractTranslator#parseText(org.apache.tapestry.form.IFormComponent,
072         *      ValidationMessages, java.lang.String)
073         */
074        protected Object parseText(IFormComponent field, ValidationMessages messages, String text)
075                throws ValidatorException
076        {
077            Format format = getFormat(messages.getLocale());
078            
079            try
080            {
081                return format.parseObject(text);
082            }
083            catch (ParseException ex)
084            {
085                throw new ValidatorException(buildMessage(messages, field, getMessageKey()),
086                        getConstraint());
087            }
088        }
089    
090        protected abstract ValidationConstraint getConstraint();
091    
092        protected abstract Format getFormat(Locale locale);
093    
094        protected abstract String getMessageKey();
095    
096        public String getPattern()
097        {
098            return _pattern;
099        }
100    
101        public void setPattern(String pattern)
102        {
103            _pattern = pattern;
104        }
105    
106        /**
107         * Gets the pattern encapsulated by this translator, subclasses may optionally use the
108         * passed in {@link Locale} to return patterns specific to that locale.
109         * 
110         * @param locale The locale to use to format the pattern, if applicable.
111         * @return The pattern used to format/parse objects.
112         */
113        public String getPattern(Locale locale)
114        {
115            return _pattern;
116        }
117    }