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 * http://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.codec.net;
19
20 import org.apache.commons.codec.DecoderException;
21
22 /**
23 * Utility methods for this package.
24 *
25 * <p>This class is immutable and thread-safe.</p>
26 *
27 * @version $Id$
28 * @since 1.4
29 */
30 class Utils {
31
32 /**
33 * Returns the numeric value of the character <code>b</code> in radix 16.
34 *
35 * @param b
36 * The byte to be converted.
37 * @return The numeric value represented by the character in radix 16.
38 *
39 * @throws DecoderException
40 * Thrown when the byte is not valid per {@link Character#digit(char,int)}
41 */
42 static int digit16(final byte b) throws DecoderException {
43 final int i = Character.digit((char) b, URLCodec.RADIX);
44 if (i == -1) {
45 throw new DecoderException("Invalid URL encoding: not a valid digit (radix " + URLCodec.RADIX + "): " + b);
46 }
47 return i;
48 }
49
50 }