Java获取URL中的顶级域名domain的工具类

方式一：

 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.Arrays;
 import java.util.HashSet;
 import java.util.Set;
 import java.util.regex.Pattern;

 public class URLUtil {

     private final static Set<String> PublicSuffixSet = new HashSet<String>(
             Arrays.asList(new String(
                     "com|org|net|gov|edu|co|tv|mobi|info|asia|xxx|onion|cn|com.cn|edu.cn|gov.cn|net.cn|org.cn|jp|kr|tw|com.hk|hk|com.hk|org.hk|se|com.se|org.se")
                     .split("\\|")));

     private static Pattern IP_PATTERN = Pattern.compile("(\\d{1,3}\\.){3}(\\d{1,3})");

     /**
      * 获取url的顶级域名
      * @param url
      * @return
      */
     public static String getDomainName(URL url) {
         String host = url.getHost();
         if (host.endsWith(".")){
             host = host.substring(0, host.length() - 1);
         }
         if (IP_PATTERN.matcher(host).matches()){
             return host;
         }

         int index = 0;
         String candidate = host;
         for (; index >= 0;) {
             index = candidate.indexOf('.');
             String subCandidate = candidate.substring(index + 1);
             if (PublicSuffixSet.contains(subCandidate)) {
                 return candidate;
             }
             candidate = subCandidate;
         }
         return candidate;
     }

     /**
      * 获取url的顶级域名
      * @param url
      * @return
      * @throws MalformedURLException
      */
     public static String getDomainName(String url) throws MalformedURLException {
         return getDomainName(new URL(url));
     }

     /**
      * 判断两个url顶级域名是否相等
      * @param url1
      * @param url2
      * @return
      */
     public static boolean isSameDomainName(URL url1, URL url2) {
         return getDomainName(url1).equalsIgnoreCase(getDomainName(url2));
     }

     /**
      * 判断两个url顶级域名是否相等
      * @param url1
      * @param url2
      * @return
      * @throws MalformedURLException
      */
     public static boolean isSameDomainName(String url1, String url2)
             throws MalformedURLException {
         return isSameDomainName(new URL(url1), new URL(url2));
     }

     public static void main(String[] args) throws Exception {
         String urlStr = "http://news.hexun.com/2017-09-23/190978248.html";
         getDomainName(urlStr);
         getDomainName(new URL(urlStr));
     }

 }

方式二：

 import java.net.MalformedURLException;
 import java.net.URL;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;

 public class DomainUtils {
     /**
      * 获取url的顶级域名
      * @param
      * @return
      */
     public static String getTopDomain(String url){
         try{
             //获取值转换为小写
             String host = new URL(url).getHost().toLowerCase();//news.hexun.com
             Pattern pattern = Pattern.compile("[^\\.]+(\\.com\\.cn|\\.net\\.cn|\\.org\\.cn|\\.gov\\.cn|\\.com|\\.net|\\.cn|\\.org|\\.cc|\\.me|\\.tel|\\.mobi|\\.asia|\\.biz|\\.info|\\.name|\\.tv|\\.hk|\\.公司|\\.中国|\\.网络)");
             Matcher matcher = pattern.matcher(host);
             while(matcher.find()){
                 return matcher.group();
             }
         }catch(MalformedURLException e){
             e.printStackTrace();
         }
         return null;
     }
     public static void main(String[] args) {
         System.out.println(getTopDomain("http://news.hexun.com/2017-09-23/190978248.html"));//hexun.com

     }
 }