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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  
18  package org.apache.commons.beanutils2.locale.converters;
19  
20  import java.math.BigDecimal;
21  import java.math.BigInteger;
22  import java.text.DecimalFormat;
23  import java.text.NumberFormat;
24  import java.text.ParseException;
25  import java.text.SimpleDateFormat;
26  import java.util.Date;
27  import java.util.Locale;
28  
29  import org.apache.commons.beanutils2.ConversionException;
30  import org.apache.commons.beanutils2.locale.BaseLocaleConverter;
31  import org.apache.commons.beanutils2.locale.LocaleConverter;
32  import org.apache.commons.logging.Log;
33  import org.apache.commons.logging.LogFactory;
34  
35  /**
36   * Standard {@link org.apache.commons.beanutils2.locale.LocaleConverter} implementation that converts an incoming locale-sensitive object into a {@link String}
37   * object, optionally using a default value or throwing a {@link org.apache.commons.beanutils2.ConversionException} if a conversion error occurs.
38   */
39  public class StringLocaleConverter extends BaseLocaleConverter<String> {
40  
41      /**
42       * Builds instances of {@link StringLocaleConverter}.
43       */
44      public static class Builder extends BaseLocaleConverter.Builder<Builder, String> {
45  
46          /**
47           * Constructs a new instance.
48           */
49          public Builder() {
50              // empty
51          }
52  
53          /**
54           * Gets a new instance.
55           * <p>
56           * Defaults construct a {@link LocaleConverter} that will throw a {@link ConversionException} if a conversion error occurs. The locale is the default
57           * locale for this instance of the Java Virtual Machine and an unlocalized pattern is used for the conversion.
58           * </p>
59           *
60           * @return a new instance.
61           */
62          @Override
63          public StringLocaleConverter get() {
64              return new StringLocaleConverter(defaultValue, locale, pattern, useDefault || defaultValue != null, localizedPattern);
65          }
66  
67      }
68  
69      /** All logging goes through this logger */
70      private static final Log LOG = LogFactory.getLog(StringLocaleConverter.class);
71  
72      /**
73       * Constructs a new builder.
74       *
75       * @return a new builder.
76       */
77      public static Builder builder() {
78          return new Builder();
79      }
80  
81      private StringLocaleConverter(final String defaultValue, final Locale locale, final String pattern, final boolean useDefault, final boolean locPattern) {
82          super(defaultValue, locale, pattern, useDefault, locPattern);
83      }
84  
85      /**
86       * Gets an instance of DecimalFormat.
87       *
88       * @param locale  The locale
89       * @param pattern The pattern is used for the conversion
90       * @return The format for the locale and pattern
91       * @throws ConversionException      if conversion cannot be performed successfully
92       * @throws IllegalArgumentException if an error occurs parsing a String to a Number
93       */
94      private DecimalFormat getDecimalFormat(final Locale locale, final String pattern) {
95          final DecimalFormat numberFormat = (DecimalFormat) NumberFormat.getInstance(locale);
96  
97          // if some constructors default pattern to null, it makes only sense to handle null pattern gracefully
98          if (pattern != null) {
99              if (localizedPattern) {
100                 numberFormat.applyLocalizedPattern(pattern);
101             } else {
102                 numberFormat.applyPattern(pattern);
103             }
104         } else {
105             LOG.debug("No pattern provided, using default.");
106         }
107 
108         return numberFormat;
109     }
110 
111     /**
112      * Parses the specified locale-sensitive input object into an output object of the specified type.
113      *
114      * @param value   The input object to be converted
115      * @param pattern The pattern is used for the conversion
116      * @return The converted value
117      * @throws ConversionException if conversion cannot be performed successfully
118      * @throws ParseException      if an error occurs
119      */
120     @Override
121     protected String parse(final Object value, final String pattern) throws ParseException {
122         String result = null;
123 
124         if (value instanceof Integer || value instanceof Long || value instanceof BigInteger || value instanceof Byte || value instanceof Short) {
125             result = getDecimalFormat(locale, pattern).format(((Number) value).longValue());
126         } else if (value instanceof Double || value instanceof BigDecimal || value instanceof Float) {
127             result = getDecimalFormat(locale, pattern).format(((Number) value).doubleValue());
128         } else if (value instanceof Date) { // java.util.Date, java.sql.Date, java.sql.Time, java.sql.Timestamp
129             result = new SimpleDateFormat(pattern, locale).format(value);
130         } else {
131             result = value.toString();
132         }
133 
134         return result;
135     }
136 }