Gradle fails when building Android Studio project - app:compileDebugJavaWithJavac

I have Android Studio project, I keep getting an error whenever I try to build my project. The error message says:

Error:Execution failed for task ‘:app:compileDebugJavaWithJavac’.
> dagger.internal.codegen.Util$CodeGenerationIncompleteException: Unknown type returned as .

Screenshot:

My grade file has the following:

=============================================================
apply plugin: ‘com.android.application’

android {
compileSdkVersion 23
buildToolsVersion “23.0.2”
useLibrary ‘org.apache.http.legacy’

defaultConfig {
    applicationId "com.ez3"
    minSdkVersion 22
    targetSdkVersion 23
    versionCode 1
    versionName "1.0"

    // Enabling multidex support.
    multiDexEnabled true
}
buildTypes {
    release {
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
    }
}

}

repositories {
mavenCentral()

maven { url 'https://maven.fabric.io/public' }
maven { url "https://jitpack.io" }
maven {
    url "https://raw.github.com/embarkmobile/zxing-android-minimal/mvn-repo/maven-repository/"
}

}

dependencies {
compile fileTree(dir: ‘libs’, include: [’*.jar’])
testCompile ‘junit:junit:4.12’

compile files('libs/dagger-1.2.2.jar')
provided files('libs/dagger-compiler-1.2.2.jar')
provided 'com.squareup.dagger:dagger-compiler:1.2.2'
compile 'com.squareup.okhttp:okhttp:2.3.0'
compile 'com.android.support:multidex:1.0.0'

compile 'com.android.support:appcompat-v7:23.1.1'
compile 'com.android.support:design:23.1.1'
compile 'com.edmodo:cropper:1.0.1'
compile 'com.astuetz:pagerslidingtabstrip:1.0.1'
compile 'com.google.android.gms:play-services:8.4.0'
compile 'com.github.chrisbanes.photoview:library:1.2.2'
compile 'net.zetetic:android-database-sqlcipher:3.3.1-2'
compile 'com.squareup.retrofit:retrofit:1.9.0'
compile 'com.squareup:otto:1.3.5'
compile 'org.slf4j:slf4j-simple:1.6.1'
compile 'se.emilsjolander:stickylistheaders:2.1.5'
compile 'se.emilsjolander:stickylistheaders:2.5.2'

compile 'com.google.zxing:core:2.2'
compile 'com.embarkmobile:zxing-android-minimal:1.2.1@aar'
compile 'org.apache.httpcomponents:httpcore:4.4.1'
compile 'org.apache.httpcomponents:httpclient:4.2.2'
compile('com.crashlytics.sdk.android:crashlytics:2.2.2@aar') {
    transitive = true;
}
compile('de.keyboardsurfer.android.widget:crouton:1.8.5@aar') {
    // exclusion is not necessary, but generally a good idea.
    exclude group: 'com.google.android', module: 'support-v4'
}
compile 'commons-codec:commons-codec:1.5'
compile 'com.squareup.picasso:picasso:2.5.2'
compile 'org.twitter4j:twitter4j-core:4.0.3'
compile 'com.github.JakeWharton:ViewPagerIndicator:2.4.1'

}

=============================================================

I appreciate if anyone has a clue on the cause of this error/how to fix it?

Regards,

This is unrelated to Gradle, the error is coming from the Dagger code generator. It would be best to ask for help on the Dagger forum.