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1   /*
2    * Copyright 2009 Red Hat, Inc.
3    *
4    * Red Hat licenses this file to you under the Apache License, version 2.0
5    * (the "License"); you may not use this file except in compliance with the
6    * License.  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, WITHOUT
12   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
13   * License for the specific language governing permissions and limitations
14   * under the License.
15   */
16  package org.jboss.netty.util.internal;
17  
18  import java.util.ArrayList;
19  import java.util.List;
20  
21  /**
22   * Conversion utility class to parse a property represented as a string or
23   * an object.
24   *
25   * @author <a href="http://www.jboss.org/netty/">The Netty Project</a>
26   * @author <a href="http://gleamynode.net/">Trustin Lee</a>
27   *
28   * @version $Rev: 2080 $, $Date: 2010-01-26 18:04:19 +0900 (Tue, 26 Jan 2010) $
29   *
30   */
31  public class ConversionUtil {
32  
33      /**
34       * Converts the specified object into an integer.
35       */
36      public static int toInt(Object value) {
37          if (value instanceof Number) {
38              return ((Number) value).intValue();
39          } else {
40              return Integer.parseInt(String.valueOf(value));
41          }
42      }
43  
44      /**
45       * Converts the specified object into a boolean.
46       */
47      public static boolean toBoolean(Object value) {
48          if (value instanceof Boolean) {
49              return ((Boolean) value).booleanValue();
50          }
51          if (value instanceof Number) {
52              return ((Number) value).intValue() != 0;
53          } else {
54              String s = String.valueOf(value);
55              if (s.length() == 0) {
56                  return false;
57              }
58  
59              try {
60                  return Integer.parseInt(s) != 0;
61              } catch (NumberFormatException e) {
62                  // Proceed
63              }
64  
65              switch (Character.toUpperCase(s.charAt(0))) {
66              case 'T': case 'Y':
67                  return true;
68              }
69              return false;
70          }
71      }
72  
73      /**
74       * Converts the specified object into an array of strings.
75       */
76      public static String[] toStringArray(Object value) {
77          if (value instanceof String[]) {
78              return (String[]) value;
79          }
80  
81          if (value instanceof Iterable<?>) {
82              List<String> answer = new ArrayList<String>();
83              for (Object v: (Iterable<?>) value) {
84                  if (v == null) {
85                      answer.add(null);
86                  } else {
87                      answer.add(String.valueOf(v));
88                  }
89              }
90              return answer.toArray(new String[answer.size()]);
91          }
92  
93          return String.valueOf(value).split("[, \\t\\n\\r\\f\\e\\a]");
94      }
95  
96      private static final String[] INTEGERS = {
97          "0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
98          "10","11","12","13","14","15",
99      };
100 
101     public static String toString(int value) {
102         if (value >= 0 && value < INTEGERS.length) {
103             return INTEGERS[value];
104         } else {
105             return Integer.toString(value);
106         }
107     }
108 
109     private ConversionUtil() {
110         // Unused
111     }
112 }