How to import a maven module to an Android Studio project

See Migrating from Maven to Gradle. Just execute gradle init.

Go to your project then goto the app. You will see a build.gradle file under app (DO NOT use the gradle under gradle folder but the ine under app folder). Add this line.

 dependencies {
....
compile 'com.squareup.retrofit:retrofit:1.9.0'

...

}

Then, make sure that you define the repository details in directory and add the url.

 repositories {
        flatDir {
            dirs 'libs'
        }
        maven { url 'http://download.crashlytics.com/maven' }
    }``

Use a custom group and/or artifact in the POM of your clone, so your clone cannot be confused with the original.

Build and install your clone of Retrofit using Maven as usual: mvn install. (Using the command line or an IDE other than Android Studio.) You have to build your Retrofit clone manually after each change you make to it, for Gradle to see the changes.

Add the local Maven repository to your Gradle script. See https://docs.gradle.org/2.5/dsl/org.gradle.api.artifacts.dsl.RepositoryHandler.html#org.gradle.api.artifacts.dsl.RepositoryHandler:mavenLocal():

repositories {
    mavenLocal()
}

Add the GAV of your clone as a dependency to your Gradle script:

dependencies {
    compile 'com.yourgroup:retrofit:1.9.0-custom'
}

Just add it to the dependencies { } block of your application's build.gradle file.

dependencies {
    compile 'com.squareup.retrofit:retrofit:1.9.0'
}