Program type already present: com.loopj.android.http.AsyncHttpClient$3

Question

I am trying to build an app, but it failed compiling. I've tried to clean project, and when I tried to rebuild project, the same error appear.

I got this error from logcat:

Program type already present: com.loopj.android.http.AsyncHttpClient$3
Message{kind=ERROR, text=Program type already present: com.loopj.android.http.AsyncHttpClient$3, sources=[Unknown source file], tool name=Optional.of(D8)}

and this is my build.gradle:

apply plugin: 'com.android.application'

android {
compileSdkVersion 24
buildToolsVersion '27.0.3'
defaultConfig {
    applicationId "com.example.joao.cafeclientapp"
    minSdkVersion 21
    targetSdkVersion 24
    versionCode 1
    versionName "1.0"
    testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    vectorDrawables.useSupportLibrary = true
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}
}

repositories {
maven { url "https://jitpack.io" }
}

dependencies {
implementation fileTree(include: ['*.jar'], dir: 'libs')
androidTestImplementation('com.android.support.test.espresso:espresso-core:2.2.2', {
    exclude group: 'com.android.support', module: 'support-annotations'
})
implementation 'com.android.support:appcompat-v7:24.2.1'
implementation 'com.android.support:design:24.2.1'
testImplementation 'junit:junit:4.12'
implementation 'com.loopj.android:android-async-http:1.4.9'
implementation files('libs/android-async-http-1.4.9.jar')
implementation 'com.android.support:recyclerview-v7:24.2.1'
implementation 'com.github.dbachelder:CreditCardEntry:1.4.7'
implementation 'com.google.code.gson:gson:2.7'
implementation 'com.google.zxing:core:3.3.0'
implementation 'com.getbase:floatingactionbutton:1.10.1'
}

Answer 1

implementation 'com.loopj.android:android-async-http:1.4.9'
implementation files('libs/android-async-http-1.4.9.jar')

Just remove the second line and it should be fine.