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1   /*
2    * Copyright 2001-2004 The Apache Software Foundation.
3    * 
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    * 
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    * 
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */ 
16  
17  
18  package org.apache.commons.beanutils.converters;
19  
20  
21  import java.util.List;
22  import org.apache.commons.beanutils.ConversionException;
23  import org.apache.commons.beanutils.Converter;
24  
25  
26  /**
27   * <p>Standard {@link Converter} implementation that converts an incoming
28   * String into a primitive array of float.  On a conversion failure, returns
29   * a specified default value or throws a {@link ConversionException} depending
30   * on how this instance is constructed.</p>
31   *
32   * @author Craig R. McClanahan
33   * @version $Revision: 1.7 $ $Date: 2004/02/28 13:18:34 $
34   * @since 1.4
35   */
36  
37  public final class FloatArrayConverter extends AbstractArrayConverter {
38  
39  
40      // ----------------------------------------------------------- Constructors
41  
42  
43      /**
44       * Create a {@link Converter} that will throw a {@link ConversionException}
45       * if a conversion error occurs.
46       */
47      public FloatArrayConverter() {
48  
49          this.defaultValue = null;
50          this.useDefault = false;
51  
52      }
53  
54  
55      /**
56       * Create a {@link Converter} that will return the specified default value
57       * if a conversion error occurs.
58       *
59       * @param defaultValue The default value to be returned
60       */
61      public FloatArrayConverter(Object defaultValue) {
62  
63          this.defaultValue = defaultValue;
64          this.useDefault = true;
65  
66      }
67  
68  
69      // ------------------------------------------------------- Static Variables
70  
71  
72      /**
73       * <p>Model object for type comparisons.</p>
74       */
75      private static float model[] = new float[0];
76  
77  
78      // --------------------------------------------------------- Public Methods
79  
80  
81      /**
82       * Convert the specified input object into an output object of the
83       * specified type.
84       *
85       * @param type Data type to which this value should be converted
86       * @param value The input value to be converted
87       *
88       * @exception ConversionException if conversion cannot be performed
89       *  successfully
90       */
91      public Object convert(Class type, Object value) {
92  
93          // Deal with a null value
94          if (value == null) {
95              if (useDefault) {
96                  return (defaultValue);
97              } else {
98                  throw new ConversionException("No value specified");
99              }
100         }
101 
102         // Deal with the no-conversion-needed case
103         if (model.getClass() == value.getClass()) {
104             return (value);
105         }
106 
107         // Deal with input value as a String array
108         if (strings.getClass() == value.getClass()) {
109             try {
110                 String values[] = (String[]) value;
111                 float results[] = new float[values.length];
112                 for (int i = 0; i < values.length; i++) {
113                     results[i] = Float.parseFloat(values[i]);
114                 }
115                 return (results);
116             } catch (Exception e) {
117                 if (useDefault) {
118                     return (defaultValue);
119                 } else {
120                     throw new ConversionException(value.toString(), e);
121                 }
122             }
123         }
124 
125         // Parse the input value as a String into elements
126         // and convert to the appropriate type
127         try {
128             List list = parseElements(value.toString());
129             float results[] = new float[list.size()];
130             for (int i = 0; i < results.length; i++) {
131                 results[i] = Float.parseFloat((String) list.get(i));
132             }
133             return (results);
134         } catch (Exception e) {
135             if (useDefault) {
136                 return (defaultValue);
137             } else {
138                 throw new ConversionException(value.toString(), e);
139             }
140         }
141 
142     }
143 
144 
145 }