Tomcat: use FTP connection via JNDI [closed]

问题:

I need to access an FTP server from my Web Application which runs on Tomcat 6. I want to use JNDI to do this.

How can I configure this FTP connection in Tomcat using JNDI? What do I have to write into web.xml and context.xml to configure the resource? And how can I then access this connection from the Java source code?

回答1:

From this post : http://codelevain.wordpress.com/2010/12/18/url-as-jndi-resource/

Define your FTP URL in your context.xml like this :

 <Resource name="url/SomeService" auth="Container"
 type="java.net.URL"
 factory="com.mycompany.common.URLFactory"
 url="ftp://ftpserver/folder" />

Provide the com.mycompany.common.URLFactory implementation and make sure the resulting class is available to Tomcat :

import java.net.URL;
import java.util.Hashtable;
import javax.naming.*;
import javax.naming.spi.ObjectFactory;

public class URLFactory implements ObjectFactory {
 public Object getObjectInstance(Object obj, Name name, Context nameCtx, Hashtable environment) throws Exception {
 Reference ref = (Reference) obj;
 String urlString =  (String) ref.get("url").getContent();
 return new URL(urlString);
 }
}

Create your reference in web.xml

<resource-ref>
 <res-ref-name>
   url/SomeService
 </res-ref-name>
 <res-type>
   java.net.URL
 </res-type>
 <res-auth>
   Container
 </res-auth>
</resource-ref>

Then in your code obtain the FTP URL by doing a JNDI lookup:

InitialContext context = new InitialContext();
URL url = (URL) context.lookup("java:comp/env/url/SomeService");

回答2:

You do not need JNDI for that. Just use an URLConnection Java class with an URL starting with "ftp:", see e. g. URL Connection (FTP) in Java - Simple Question