How to add classpath in an Android Studio project

Question

I have an Android project with an Android application that depends on a pure Java library (and the Java library uses some others compiled jars libraries).
I added the de

Answer 1

Thanks to Arnold Layne, I created a folder named libs.

Then, I went to

Files -> Project Structure (new menu opens) -> Modules (on the left) -> app -> Dependencies

There, I could add the library with the + Button.

This created this entry:

dependencies {
    implementation files('libs/commons-lang3-3.7.jar')
}

Answer 2

Add this lines to build.gradle of app module.

dependencies {
    ...
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation files('libs/mysql-connector-java-8.0.16')
    ...
}

Answer 3

First off all, be sure there's a "libs" subfolder in the "app" folder of your project. If there's not, create one. Next, in the app/build.gradle file, add this line of code:

dependencies {
    ...
    compile fileTree(dir:'libs', include: ['*.jar'])
    ...
}

Place all of your .jar files in the "libs" folder, and voila, you're done