UnityBaseActivity/app/build.gradle

apply plugin: 'com.android.library'

android {
    compileSdkVersion 25
    buildToolsVersion "25.0.1"
    sourceSets {
        main {
            java {
                srcDir 'src/main/java'
            }
        }
    }
    defaultConfig {
        minSdkVersion 9
        targetSdkVersion 25
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(include: ['*.jar'], dir: 'libs')
    compile 'com.android.support:appcompat-v7:25.0.1'
    compile files('libs/classes.jar')
}

//task to delete the old jar
task dreamlandDeleteOldJar(type: Delete) {
    delete 'release/AndroidBasePlugin.jar'
}

task dreamlandExportUnityAndroidJar(type: Copy) {
    from('build/intermediates/intermediate-jars/release')
    into('release/')
    include('classes.jar')
    ///Rename the jar
    rename('classes.jar', 'AndroidBasePlugin.jar')
}

dreamlandExportUnityAndroidJar.dependsOn(dreamlandDeleteOldJar, build)