Improve 2.0 XML Simplexml converter problem, while having retrolambda in a gradle file

compile ('com.squareup.retrofit2:converter-simplexml:2.0.0-beta4'){
 exclude module:'stax-api'< br /> exclude module:'stax'
 exclude module:'xpp3'
}

This is my gradle file

apply plugin:'com.android.application'
apply plugin:'me.tatarka.retrolambda'
android {
 compileSdkVersion 23
 buildToolsVersion "23.0.2"

 defaultConfig {
 applicationId "com.demo.sample"
 minSdkVersion 15
 targetSdkVersion 23
 versionCode 1
 versionName "1.0"
 }
 buildTypes {
 release {
 minifyEnabled false
 proguardFiles getDefaultProguardFile('proguard-android.txt'),'proguard-rules. pro'
 }
 }

 compileOptions {
 sourceCompatibility JavaVersion.VERSION_1_8
 targetCompatibility JavaVersion.VERSION_1_8
 }
}

dependencies {
 compile fileTree(dir:'libs', include: ['*.jar'])
 testCompile'junit:junit:4.12'
 compile'com.android.support:appcompat-v7:23.2.0'
 compile'com.android.support:design:23.2.0'

 //Retrofit
 compile 'com.squareup.retrofit2:retrofit:2.0.0-beta4'
 //Retrofit support libraries
 compile'com.squareup.retrofit2:converter-gson:2.0.0-beta4'
 //compile'com.squareup.retrofit2:converter-simplexml:2.0.0-beta4'
 compile'com.squareup.retrofit2:adapter-rxjava:2.0.0-beta4'
 compile'com. squareup.okhttp3:logging-interceptor:3.0.1'
 //RxAndroid
 compile'io.reactivex:rxandroid:1.1.0'
 //Explicit support for latest RxJava
 compile'io.reactivex:rxjava:1.1.0'
 //Square dagger
 provided'com.squareup.dagger:dagger-compiler:1.2.2'
 compile'com.squareup. dagger:dagger:1.2.2'
 //Butterknife
 compile'com.jakewharton:butterknife:6.1.0'
 //Picasso
 compile'com.squareup.picasso: picasso:2.3.3'
 //Testing dependency
 testCompile'junit:junit:4.12'
 testCompile'org.assertj:assertj-core:2.1.0'
 testCompile'org.mockito:mockito-core:2.0.23-beta'
 }

If I uncomment the line to compile’com.squareup.retrofit2: converter-simplexml: 2.0.0-beta4′ android studio throws annoying errors when compiling

:app:transformClassesWithDexForDebug
trouble processing "javax/xml/XMLConstants.class":
Ill-advised or mistaken usage of a core class (java.* or javax.*) 
when not building a core library.
This is often due to inadvertently including a core library file
in your application's project, when using an IDE (such as
Eclipse). If you are sure you're not intentionally defining a
core class, then this is the most likely explanation of what's
going on.
However, you might actually be trying to define a class in a core
namespace, the source of which you may have taken, for example,
from a non-Android virtual machine project. This will most
assuredly not work. At a minimum, it jeopardizes the
compatibility of your app with future versions of the platform.
It is also often of questionable legality.
If you really intend to build a core library - which is only
appropriate as part of creating a full virtual machine
distribution, as opposed to compiling an application - then use
the "--core-library" option to suppress this error message.
 If you go ahead and use "--core-library" but are in fact
building an application, then be forewarned that your application
will still fail to build or run, at some point. Please be< br />prepared for angry customers who find, for example, that your
application ceases to function once they upgrade their operating
system. You will be to blame for this problem.
If you are legitimately using some code that happens to be in a
core package, then the easiest safe alternative you have is to
repackage that code. That is, move the classes in question into
your own package namespace. This means that they will never be in
conflict with core system classes. JarJar is a tool that may help
you in this endeavor. If you find that you cannot do this, then
that is an indication that the path you are on will ultimately
lead to pain, suffering, grief, and lamentation.
1 error; aborting
Error:Execution failed for task':app :transformClassesWithDexForDebug'.
> com.android.ide.common.process.ProcessException: org.gradle.process.internal.ExecException: Process'command'/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents /Home/bin/java'' finished with non-zero exit value 1

I don’t understand what this error means. Also, there is a way to solve this problem.

It looks like Simple XML has transitive dependencies already included in Android. See https://github.com/square/retrofit/issues/1536.
We need to exclude three Two dependencies: stax: stax-api, stax: stax and xpp3: xpp3.
I managed to achieve this by using this compilation statement in gradle

< pre>compile (‘com.squareup.retrofit2:converter-simplexml:2.0.0-beta4’){
exclude module:’stax-api’< br /> exclude module:’stax’
exclude module:’xpp3′
}