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Error: android defines classes that conflict with classes now provided by Android , when we start to generate release build

I had several libraries conflict issues. That i resolved by adding
configurations {
all {
exclude module: 'httpclient'
exclude module: 'commons-logging'
exclude group: 'org.json', module: 'json'
exclude group: 'org.apache.httpcomponents'
exclude module: 'xmlParserAPIs'
exclude module: 'xpp3'
exclude module: 'opengl-api'
}
}
But still following error present. And i am unable to build signed apk.
I have tried project clean/rebuild option.
Error: android defines classes that conflict with classes now provided by Android. Solutions include finding newer versions or alternative libraries that don't have the same problem (for example, for httpclient use HttpUrlConnection or okhttp instead), or repackaging the library using something like jarjar. [DuplicatePlatformClasses]
Thanks in advance for your help.

Problem
How to see which dependency is creating conflicts. It is same like shooting in dark.
Solution
Some AS plugin that will show you which projects dependency hierarchy. You can find where issue presents exactly and solve that.
Gradle View is an Android Studio plugin that you can install and show dependency hierarchy.
Methods Count is another plugin, it also shows dependency tree.

The error may be comes from different module but if issue is httpcomp... or xpp3 then
I just add these lines of code in app Gradle
dependencies {
......
configurations {
all*.exclude group: 'xpp3', module: 'xpp3'
implementation.exclude group: "org.apache.httpcomponents", module: "httpclient"
}
}
done

Error when adding RxPresso to project

I got this error message when trying to add RxPresso(https://github.com/novoda/rxpresso/) to my project:
Warning:Conflict with dependency 'io.reactivex:rxjava'. Resolved versions for app (1.1.9) and test app (1.0.14) differ. See http://g.co/androidstudio/app-test-app-conflict for details.
I'm currently using rxjava 1.1.9. How can I add RxPresso in my project?
Thx a lot

To avoid any problems with RxJava and Android Support Libraries version, go to your app/build.gradle file and in dependencies section paste:
androidTestCompile ('com.novoda:rxpresso:0.2.0') {
exclude group: 'com.android.support', module: 'support-annotations'
exclude group: 'io.reactivex'
}

You can explicitly tell Gradle which version to use, by adding into your build.gradle next snippet
configurations.all {
// check dependency tree with gradlew :app:dependencies
// avoid wildcard '+' dependencies used at 3rd libraries forcing them to exact version
resolutionStrategy.force "io.reactivex:rxjava:1.1.9"
}

Not able to remove transitive dependency from gradle in an Android Project

I am trying to remove the transitive dependencies from my Android project and for some reason exclude is not working when i try to remove a dependency from my particular dependency.
For example i want to remove support-annotations from my project
if i use
configurations {
all*.exclude group: 'com.android.support', module:'support-annotations'
}
The dependency gets excluded and from the dependency tree. i can see the dependency tree by using ./gradlew app:dependencies
But if i use
compile('com.android.support:support-v4:23.4.0')
{
exclude group: 'com.android.support', module:'support-annotations'
}
Then i still see the dependency in the dependency tree.
So my question is that why is it not working when i try to remove the dependency from a particular dependency ?
Update 1:
Also can anyone tell me what does the star (*) symbol next to dependency in the tree represent ?
Update 2
I am also using Fresco I tried the same thing with Fresco and exclude rule seems to work for it
Dependency Tree of Fresco
Dependency Tree when i exclude imagepipeline-base in Fresco
compile("com.facebook.fresco:fresco:0.9.0")
{
exclude group: 'com.facebook.fresco', module: 'imagepipeline-base'
}
As you can see the imagepipeline-base dependency gets excluded. So i don't know why this doesn't work for Android Support Annotations transitive dependency

So i have figured this out with the help of one of my friends. The reason why i was not able to remove support-annotation was because most of the other dependencies were using support-v4 as transitive dependency and those support-v4 also had their own copy of support-annotation.
Now there are 2 solutions to this
Solution 1:
exclude support-annotation from all the dependencies that containsupport-v4 as transitive dependency.
Solution 2:
exclude support-annotation only from my support-v4 dependency and remove support-v4 dependency from all other dependencies that have support-v4 as transitive dependency.
Note: Using one of the above approaches i was able to solve my problem and figure out how we can remove transitive dependencies when they are referenced from multiple dependencies.
And regarding the ( * ) symbol it means that the dependency tree is for that dependency is already shown. Instead of showing the whole tree for those dependencies again gradle shows ( * ) symbol with them.
Sample build.gradle file is available here

There is more graceful solution: you can use configueation.all block in your build.gradle file like in example below:
configurations.all {
exclude group: 'com.android.support', module: 'support-annotations'
}
It should exclude all transitive dependencies from all inner modules in your application.

In an Android Gradle build, how to exclude dependencies from an included jar file?

In my Android project, I use a library that comes as a jar.
I include it in the dependencies section like so:
dependencies {
...
compile files('libs/thethirdpartylibrary.jar')
...
}
I also want to use the okhttp library, which I include like this:
compile ('com.squareup.okhttp:okhttp:2.7.5')
(This particular version of okhttp depends on okio 1.6.0.)
The problem is that the thirdparty jar library depends on okio v0.9.0 and what's worse, bundles it.
As a result, I get a dex conflict error at build time.
I was able to resolve this by manually removing okio from the jar file and this seems to work. But I'm wondering if there's a way to do this in gradle.
My question: Can I remove bundled, transitive ( <- I hope I'm using this word the right way) dependencies from an included jar during build-time with gradle?

Exclude the Group in the dependencies by using the below lines.
1.
configurations {
all*.exclude group: 'com.android.support', module: 'support-v4'
}
2.
dependencies {
compile 'com.android.support:support-v4:13.0.+'
compile ("com.xxx:xxx-commons:1.+") {
exclude group: 'junit', module: 'junit'
}
}
3.
configurations {
runtime.exclude group: "org.slf4j", module: "slf4j-log4j12"
}
Try this one.
For more detail

According to this discussion here https://groups.google.com/forum/#!topic/adt-dev/g1AiJM7PeVs, what you want to do is not possible.
The syntax suggested in the other answers is for "normal" Maven dependencies.

How to exclude module from all dependencies but leave explicit declaration Gradle

I am trying to solve the problem,
I have some dependencies declared in build.gradle file for my android app, but the problem is that a lot of these dependencies use the same compat library, in my case appcompat-v7.
It is possible to exclude this library for each dependency
compile ('com.github......'){
exclude group: 'com.android.support', module: 'appcompat-v7'
}
But I need to do this in for each dependency
Another way is to use such expression
configurations {
compile.exclude module: 'appcompat-v7'
}
This works, but even If declare this library explicitly it is ignored compile 'com.android.support:appcompat-v7:+'
All what I need it is to include this library only once for the whole app, because if compile without exclude it will show a lot of errors like has been already defined.
Maybe there is an easier way to get this working. I would be grateful for any help, thanks.

We use a provided configuration in gradle (so that when we gradle:eclipse, the packages are included, but are not included when compiled into a jar, as these jars are expected to be provided at runtime). This configuration looks like the following:
configurations {
provided {
dependencies.all {dep ->
configurations.default.exclude group: dep.group, module:dep.name
}
}
compile.extendsFrom provided
}
This allows us to include dependencies as follows:
dependencies {
compile("org.scala-lang:scala-library:2.11.7")
compile("org.scala-lang:scala-compiler:2.11.7")
provided("org.apache.spark:spark-core_2_11:2.0.0")
}
Try creating a configuration which contains all dependencies where you want to exclude appcompat-v7, and then extend compile from this new configuration.