title: "java.net.UnknownHostException" occur when read mybatis xml file
body: <p>I like to read data from following mybatis xml file by java code. (Not mybatis mapping, just want to read data form outside application.)</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd"&gt;
  &lt;mapper namespace="com.raistudies.persistence.UserService"&gt;
  
  &lt;resultMap id="result" type="user"&gt;
      &lt;result property="id" column="id"/&gt;
      &lt;result property="name" column="name"/&gt;
      &lt;result property="standard" column="standard"/&gt;
      &lt;result property="age" column="age"/&gt;
      &lt;result property="sex" column="sex"/&gt;
  &lt;/resultMap&gt;
  
  &lt;select id="getAllUser" resultMap="result"&gt;  
      SELECT id,name,standard,age,sex 
      FROM user; 
  &lt;/select&gt;
  &lt;/mapper&gt;
  </code></pre>
  
  <p>So i trying with xml reader as follow:</p>
  
  <pre><code>        File fXmlFile = new File("c:\\mybatis.xml");
          DocumentBuilderFactory dbFactory = DocumentBuilderFactory
                  .newInstance();
          DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
          Document doc = dBuilder.parse(fXmlFile);
          doc.getDocumentElement().normalize();
  
          NodeList nList = doc.getElementsByTagName("mapper");
                      .
                      .
                      .
  </code></pre>
  
  <p>But when i run this code, i got following error</p>
  
  <pre><code>java.net.UnknownHostException: mybatis.org
  at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
  at java.net.PlainSocketImpl.connect(Unknown Source)
  at java.net.SocksSocketImpl.connect(Unknown Source)
  at java.net.Socket.connect(Unknown Source)
  at java.net.Socket.connect(Unknown Source)
  at sun.net.NetworkClient.doConnect(Unknown Source)
  at sun.net.www.http.HttpClient.openServer(Unknown Source)
  at sun.net.www.http.HttpClient.openServer(Unknown Source)
  at sun.net.www.http.HttpClient.&lt;init&gt;(Unknown Source)
  at sun.net.www.http.HttpClient.New(Unknown Source)
  at sun.net.www.http.HttpClient.New(Unknown Source)
  at sun.net.www.protocol.http.HttpURLConnection.getNewHttpClient(Unknown Source)
  at sun.net.www.protocol.http.HttpURLConnection.plainConnect(Unknown Source)
  at sun.net.www.protocol.http.HttpURLConnection.connect(Unknown Source)
  at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startEntity(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLEntityManager.startDTDEntity(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDTDScannerImpl.setInputSource(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.dispatch(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$DTDDriver.next(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
  at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
  at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
  at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
  at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
  at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(Unknown Source)
  at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(Unknown Source)
  at javax.xml.parsers.DocumentBuilder.parse(Unknown Source)
  at xmlReader.main(xmlReader.java:37)
  </code></pre>
  
  <p>I found the course of error because of this statement.</p>
  
  <pre><code>     &lt;!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 
  "http://mybatis.org/dtd/mybatis-3-mapper.dtd"&gt;
  </code></pre>
  
  <p>My all code are work properly when i remove this statement.
  Let me know, how can i overcome this problem.</p>