NullPointerException with a simple EWS program. Help.

Hi all,

I have a very simple program, using EWS. I am just trying to connect to my gmail account (Can I connect to my gmail account in the first place with EWS?). But I am getting the following error.

Code:

---

package com.my.ews.cq;

import microsoft.exchange.webservices.data.*;
import java.net.URI;



public class ConnectToExchange {

        /**
        * @param args
        */
        public static void main(String[] args) {
                // TODO Auto-generated method stub
               
                try {
                        ExchangeService service = new ExchangeService();
                        System.out.println("Got ExchangeService");
                        ExchangeCredentials credentials = new WebCredentials("myaccount@gmail.com", "xxxxxxx");
                        System.out.println("Set credentials");
                        service.setUrl(new java.net.URI("gmail.com"));
                        service.setCredentials(credentials);
                       
                        EmailMessage msg= new EmailMessage(service);
                        System.out.println("got a message instance");
                        msg.setSubject("Hello world!");
                        System.out.println("set suject to " + msg.getSubject().toString());
                        msg.setBody(MessageBody.getMessageBodyFromText("Sent using the EWS Managed API."));
                        System.out.println("set body to " + msg.getBody().toString());
                        msg.getToRecipients().add("mygmail@gmail.com");
                        //System.out.println("add recipient: " + msg.getDisplayTo().toString());
                        msg.send();
                        System.out.println("message sent");

                       
                } catch (Exception e) {
                        e.printStackTrace();
                }


        }

}

---

But, when I run this program I get the following error:

Code:

---

microsoft.exchange.webservices.data.ServiceRequestException: The request failed. null
        at microsoft.exchange.webservices.data.ServiceRequestBase.validateAndEmitRequest(Unknown Source)
        at microsoft.exchange.webservices.data.SimpleServiceRequestBase.internalExecute(Unknown Source)
        at microsoft.exchange.webservices.data.MultiResponseServiceRequest.execute(Unknown Source)
        at microsoft.exchange.webservices.data.ExchangeService.internalCreateItems(Unknown Source)
        at microsoft.exchange.webservices.data.ExchangeService.createItem(Unknown Source)
        at microsoft.exchange.webservices.data.Item.internalCreate(Unknown Source)
        at microsoft.exchange.webservices.data.EmailMessage.internalSend(Unknown Source)
        at microsoft.exchange.webservices.data.EmailMessage.send(Unknown Source)
        at com.my.ews.cq.ConnectToExchange.main(ConnectToExchange.java:39)
Caused by: java.lang.NullPointerException
        at microsoft.exchange.webservices.data.ExchangeServiceBase.prepareHttpWebRequestForUrl(Unknown Source)
        at microsoft.exchange.webservices.data.ExchangeService.prepareHttpWebRequest(Unknown Source)
        at microsoft.exchange.webservices.data.ServiceRequestBase.emit(Unknown Source)
        ... 9 more
Got ExchangeService
Set credentials
set autodiscover
got a message instance
set suject to Hello world!
set body to Sent using the EWS Managed API.

---

Please advise.

Mabye a strange question. Gmail uses its own mail server. Why do you use and Exchange class?

Good question.

I tried my company's email account which uses exchange server. And in the above code I changed the following line, adding the exchange webmail url. i.e.

service.setUrl(new java.net.URI("https://owa.mycompany.com/owa/"));


and I got this error now:

Code:

---

Got ExchangeService
Set credentials
set Credentails
set autodiscover
got a message instance
set suject to Hello world!
set body to Sent using the EWS Managed API.
microsoft.exchange.webservices.data.ServiceRequestException: The request failed. The remote server returned an error: (440)Login Timeout
        at microsoft.exchange.webservices.data.ServiceRequestBase.validateAndEmitRequest(Unknown Source)
        at microsoft.exchange.webservices.data.SimpleServiceRequestBase.internalExecute(Unknown Source)
        at microsoft.exchange.webservices.data.MultiResponseServiceRequest.execute(Unknown Source)
        at microsoft.exchange.webservices.data.ExchangeService.internalCreateItems(Unknown Source)
        at microsoft.exchange.webservices.data.ExchangeService.createItem(Unknown Source)
        at microsoft.exchange.webservices.data.Item.internalCreate(Unknown Source)
        at microsoft.exchange.webservices.data.EmailMessage.internalSend(Unknown Source)
        at microsoft.exchange.webservices.data.EmailMessage.send(Unknown Source)
        at com.my.ews.cq.ConnectToExchange.main(ConnectToExchange.java:37)
Caused by: java.lang.Exception: The remote server returned an error: (440)Login Timeout
        at microsoft.exchange.webservices.data.ServiceRequestBase.emit(Unknown Source)
        ... 9 more

---

Please advise.

Well you got 2 things:

1.Gmail isn't an exchange server, you cannot use it there.
Use the SMTP class and lookup the SMTP settings of GMail.

NullPointer means you get nothing back.

2. A logon time-out on Exchange.
Could mean they're using SSL and you have to use SSL making connection.
Maybe they host an SMTP option to at your company, you can build one solution then.

Exchange has a connector for SMTP

Thanks for the input.

I need to use EWS Java API to modify an existing application which's integrated with the exchange server. Here I am just trying to get it work for just connecting to oue exchange server. Maybe gmail was a bad idea to bring it into topic.

Let me ask another question: does protocol matter when using ews? for this particular account pop3 is enabled.

Is there any Javadoc API specs available for EWS? Can someone please point me to a link or some sample codes? Real appreciate your help folks.

Thanks.

Any help please?

I don't know EWS, but i do know that Exchange needs protocol, like SMTP to send a messega.
Logical would be that EWS uses this protocol to, because we need a protocol to sent things on the Internet.

You need to have a look on the Microsoft Forums on MSDN. Microsoft Forums: Get live and on-demand access to a wide range of technical and business guidance from industry experts.

There is more about the API.
Exchange -> Development.

Its hard to find because Microsoft uses the .Net Framework and laguages as C# or Java.

I cannot say it here ;-), but C# is fun to :-).

Thanks for the info and the reference link.

However, I have to use EWS Java API, and not .NET or C#. Otherwise, I wouldn't be here :-)

I can see the WSDL for my exchange server at https://myexchange.domain.com/ews/Services.wsdl

So, if I use this WSDL to access the services/operations, do I still need to worry about the protocol? Because I assume, it'll be like any other web services, and all we need to do is simply call the appropriate methods, is all. Am I correct in my assumption?

Please advise...


thanks.

Well when i communicate in a webservice to a tcp port i need to set the ip of the server i communicate with.

So i'm not 100 % sure

When i use the SMTP protocol i use an IP (hostname) to, smtp.company.local.nl or something like that.
But maybe in EWS Exchange does that for you.

It's a Java API, but to Exchange. On the Msdn forum i think you'll have more succes in getting the full answer.