EWS-Java-API - EmailMessage.send into java.lang.NullPointerException: format == null

Question

I want to use the EWS-Java-API for my android application. The application requires a login to get programmatically access to the microsoft exchange server (e.g. calendar meetings, email, meeting rooms, and much more).

At this point almost the entire question is edited, just in case to show the situation so far.

I try to get connected to an exchange version 15.0.11 with the url ("https ://yourserver/EWS/Exchange.asmx")

Build gradle file:

android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
useLibrary 'org.apache.http.legacy'

defaultConfig {        
    minSdkVersion 18
    targetSdkVersion 22
    versionCode 1
    versionName "1.0"
    multiDexEnabled true
}

packagingOptions {        
    exclude 'META-INF/DEPENDENCIES.txt'
    exclude 'META-INF/DEPENDENCIES'
    exclude 'META-INF/dependencies.txt'
    exclude 'META-INF/LICENSE.txt'
    exclude 'META-INF/LICENSE'
    exclude 'META-INF/license.txt'
    exclude 'META-INF/LGPL2.1'
    exclude 'META-INF/NOTICE.txt'
    exclude 'META-INF/NOTICE'
    exclude 'META-INF/notice.txt'
} [...] }

dependencies {
     compile fileTree(include: ['*.jar'], dir: 'libs')
     testCompile 'junit:junit:4.12'
     compile 'com.android.support:appcompat-v7:23.2.1'
     compile 'com.android.support:design:23.3.0'
     compile 'com.google.android.gms:play-services:6.5.87'
     compile 'org.altbeacon:android-beacon-library:2.7.1'
     compile 'org.greenrobot:eventbus:3.0.0'
     compile files('libs/jcifs-1.3.15.jar')
     compile files('libs/commons-logging-1.1.1.jar')
     compile files('libs/commons-codec-1.4.jar')
     compile files('libs/commons-httpclient-3.1.jar')
     compile 'com.microsoft.ews-java-api:ews-java-api:2.0' }

This will cause into this error message

 java.lang.NoClassDefFoundError: Failed resolution of: Lorg/apache/http/client/protocol/HttpClientContext;

Line:

ExchangeService service = new ExchangeService();      

At this point i tested this ews libary "github.com/faisons/EWS-For-Android".

 compile files('libs/ews.jar')

This is almost working. Iam able to start the application and set up the ExchangeService.

 Thread thread = new Thread(new Runnable()
    {
        @Override
        public void run()
        {
            try
            {
               ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
               ExchangeCredentials credentials = new WebCredentials(myuser, mypw);
               service.setCredentials(credentials);
               service.setUrl(new URI("https://exchmail.yourserver.com/EWS/Exchange.asmx"));
               EmailMessage message = new EmailMessage(service);
               EmailAddress from = new EmailAddress(myemail);
               message.setSender(from);                  
               message.getToRecipients().add(anotherEmail);
               message.setSubject("Much wow - such message");
               MessageBody messageBody = new MessageBody();
               messageBody.setText("text here");
               message.setBody(messageBody);
               message.send();

            } 
            catch (Exception e)
            {
                Log.e(TAG, "message", e);
            }
        }
    });

    thread.start();

The error now is:

java.lang.NullPointerException: format == null
    at java.lang.String.format(String.java:1799)
at java.lang.String.format(String.java:1777)
    at java.lang.String.format(String.java:1799)
    at microsoft.exchange.webservices.data.ServiceRequestBase.getEwsHttpWebResponse(ServiceRequestBase.java:936)
at microsoft.exchange.webservices.data.ServiceRequestBase.validateAndEmitRequest(ServiceRequestBase.java:821)
at microsoft.exchange.webservices.data.SimpleServiceRequestBase.internalExecute(SimpleServiceRequestBase.java:46)
at microsoft.exchange.webservices.data.MultiResponseServiceRequest.execute(MultiResponseServiceRequest.java:143)
at microsoft.exchange.webservices.data.ExchangeService.internalCreateItems(ExchangeService.java:463)
at microsoft.exchange.webservices.data.ExchangeService.createItem(ExchangeService.java:534)
at microsoft.exchange.webservices.data.Item.internalCreate(Item.java:215)
at microsoft.exchange.webservices.data.EmailMessage.internalSend(EmailMessage.java:125)

Iam confused how to get the api working. If somebody knows another way to get access any hint is welcome!

Answer 1

Greeting! I have good news, it works! Iam not sure if this is the perfect way, but i am able to send an Email

First of all make sure that you have the permissions declared in the manifes file:

<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

This is my Build.gradle file:

android {
compileSdkVersion 23
buildToolsVersion "23.0.1"
useLibrary 'org.apache.http.legacy'      // <---------------------

defaultConfig {
    applicationId "your application id"
    minSdkVersion 18
    targetSdkVersion 22
    versionCode 1
    versionName "1.0"
    multiDexEnabled true
}

packagingOptions {
    exclude 'META-INF/LICENSE.txt'
    exclude 'META-INF/NOTICE.txt'
    exclude 'META-INF/DEPENDENCIES.txt'
    exclude 'META-INF/DEPENDENCIES'
    exclude 'META-INF/dependencies.txt'
    exclude 'META-INF/LICENSE.txt'
    exclude 'META-INF/LICENSE'
    exclude 'META-INF/license.txt'
    exclude 'META-INF/LGPL2.1'
    exclude 'META-INF/NOTICE.txt'
    exclude 'META-INF/NOTICE'
    exclude 'META-INF/notice.txt'
}

buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}}

dependencies {
compile fileTree(include: ['*.jar'], dir: 'libs')
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.2.1'
compile 'com.android.support:design:23.3.0
compile files('libs/ews-android-api.jar')    // <---------------------
compile 'joda-time:joda-time:2.8'}           // <---------------------

You can get the ews-android-api under this link: https://github.com/alipov/ews-android-api

Just follow the building instructions to create the jar file.

This is the basic command line for sending an email (run this as async task or in a new thread):

                ExchangeService service = new ExchangeService(ExchangeVersion.Exchange2010_SP2);
                ExchangeCredentials credentials = new WebCredentials("user", "pw");
                service.setCredentials(credentials);
                service.setUrl(new URI("https:// s e r v e r /ews/exchange.asmx"));                    
                EmailAddress mEmail = new EmailAddress("your email / test email");

                EmailMessage message = new EmailMessage(service);
                message.getToRecipients().add(mEmail);
                message.setFrom(mEmail);
                message.setSubject("Hello world!");
                message.setBody(MessageBody.getMessageBodyFromText("Sent using the EWS Android API."));
                message.send();

You can check your credentials with the EWSEditor. Shout-out to DevilGeek and Alipov.

If something is not clear feel free to ask.

Kind regards!

EDIT: It seems to be working with almost everything. You do not need Office 365 in particular. For example iam able to call "service.getRoomLists();" aswell.

Answer 2

Did you add the apache legacy lines into your gradle build?

android {
    compileSdkVersion 22
    buildToolsVersion "22.0.1"
    useLibrary 'org.apache.http.legacy'
    ...
}

See this for more info: http://developer.android.com/about/versions/marshmallow/android-6.0-changes.html#behavior-apache-http-client