1   /**
2    * Copyright (c) 2000-2009 Liferay, Inc. All rights reserved.
3    *
4    *
5    *
6    *
7    * The contents of this file are subject to the terms of the Liferay Enterprise
8    * Subscription License ("License"). You may not use this file except in
9    * compliance with the License. You can obtain a copy of the License by
10   * contacting Liferay, Inc. See the License for the specific language governing
11   * permissions and limitations under the License, including but not limited to
12   * distribution rights of the Software.
13   *
14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20   * SOFTWARE.
21   */
22  
23  package com.liferay.portal.kernel.util;
24  
25  import com.liferay.portal.kernel.log.Log;
26  import com.liferay.portal.kernel.log.LogFactoryUtil;
27  
28  import java.net.InetAddress;
29  import java.net.UnknownHostException;
30  
31  /**
32   * <a href="IPDetector.java.html"><b><i>View Source</i></b></a>
33   *
34   * @author Shuyang Zhou
35   */
36  public class IPDetector {
37  
38      public static boolean isPrefersV4() {
39          if (_prefersV4 == null) {
40              _prefersV4 = Boolean.valueOf(
41                  System.getProperty("java.net.preferIPv4Stack"));
42          }
43  
44          return _prefersV4.booleanValue();
45      }
46  
47      public static boolean isPrefersV6() {
48          if (_prefersV6 == null) {
49              _prefersV6 = Boolean.valueOf(
50                  System.getProperty("java.net.preferIPv6Stack"));
51          }
52  
53          return _prefersV6.booleanValue();
54      }
55  
56      public static boolean isSupportsV6() {
57          if (_suppportsV6 == null) {
58              _suppportsV6 = Boolean.FALSE;
59  
60              try {
61                  InetAddress[] inetAddresses = InetAddress.getAllByName(
62                      "localhost");
63  
64                  for (InetAddress inetAddress : inetAddresses) {
65                      if (inetAddress.getHostAddress().contains(":")) {
66                          _suppportsV6 = Boolean.TRUE;
67  
68                          break;
69                      }
70                  }
71              }
72              catch (UnknownHostException uhe) {
73                  _log.error(uhe, uhe);
74              }
75          }
76  
77          return _suppportsV6.booleanValue();
78      }
79  
80      private static Log _log = LogFactoryUtil.getLog(IPDetector.class);
81  
82      private static Boolean _prefersV4;
83      private static Boolean _prefersV6;
84      private static Boolean _suppportsV6;
85  
86  }