mxtest.java

java与模式 一书的源码

package com.javapatterns.singleton.mxrecord1;

import java.util.Hashtable;

import javax.naming.NamingEnumeration;
import javax.naming.directory.DirContext;
import javax.naming.directory.InitialDirContext;
import javax.naming.directory.Attributes;
import javax.naming.directory.Attribute;
import javax.naming.NamingException;

public class MXTest
{
    public static void main(String[] args)
        throws NamingException
    {
        Hashtable env = new Hashtable();

        env.put("java.naming.factory.initial",
            "com.sun.jndi.dns.DnsContextFactory");
        env.put( "java.naming.provider.url",
             "dns://jupiter.jeffcorp.com");

        DirContext dirContext = new
            InitialDirContext(env);

        Attributes attrs = dirContext.getAttributes(
	        "jeffcorp.com", new String[]{"MX"});

        for(NamingEnumeration ae = attrs.getAll();
	        ae != null && ae.hasMoreElements();)
        {
            Attribute attr = (Attribute)ae.next();
            NamingEnumeration e = attr.getAll();

            while(e.hasMoreElements())
            {
                String element = e.nextElement().toString();

                System.out.println(element);
            }
        }
	}
}