1   /*
2    * Copyright (C) 2011 The Guava Authors
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5    * in compliance with the License. You may obtain a copy of the License at
6    *
7    * http://www.apache.org/licenses/LICENSE-2.0
8    *
9    * Unless required by applicable law or agreed to in writing, software distributed under the
10   * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
11   * express or implied. See the License for the specific language governing permissions and
12   * limitations under the License.
13   */
14  
15  package com.google.common.primitives;
16  
17  import com.google.common.annotations.GwtCompatible;
18  
19  /**
20   * A string to be parsed as a number and the radix to interpret it in.
21   */
22  @GwtCompatible
23  final class ParseRequest {
24    final String rawValue;
25    final int radix;
26  
27    private ParseRequest(String rawValue, int radix) {
28      this.rawValue = rawValue;
29      this.radix = radix;
30    }
31  
32    static ParseRequest fromString(String stringValue) {
33      if (stringValue.length() == 0) {
34        throw new NumberFormatException("empty string");
35      }
36  
37      // Handle radix specifier if present
38      String rawValue;
39      int radix;
40      char firstChar = stringValue.charAt(0);
41      if (stringValue.startsWith("0x") || stringValue.startsWith("0X")) {
42        rawValue = stringValue.substring(2);
43        radix = 16;
44      } else if (firstChar == '#') {
45        rawValue = stringValue.substring(1);
46        radix = 16;
47      } else if (firstChar == '0' && stringValue.length() > 1) {
48        rawValue = stringValue.substring(1);
49        radix = 8;
50      } else {
51        rawValue = stringValue;
52        radix = 10;
53      }
54  
55      return new ParseRequest(rawValue, radix);
56    }
57  }