kitisak / androiddemoin4languages

Comparison between Java, Groovy, Scala, Kotlin in Android Development.

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AndroidDemoIn4Languages

A simple Android application written in Java, Groovy, Scala and Kotlin in order to find out what is the better language for Android development.

How to Compare?

Only import the minimal dependencies.

Dependence Report

• In Java
  • Import com.android.support:appcompat-v7:23.3.0
• In Groovy
  • Import com.android.support:appcompat-v7:23.3.0
  • Import org.codehaus.groovy:groovy:2.4.6:grooid
  • Import org.codehaus.groovy:groovy-json:2.4.6
• In Scala
  • Import com.android.support:appcompat-v7:23.3.0
  • Import org.scala-lang:scala-library:2.11.7
• In Kotlin
  • Import com.android.support:appcompat-v7:23.3.0
  • Import org.jetbrains.kotlin:kotlin-stdlib:1.0.0

Analysis Report

Line Counter

Language	Files	Blank Lines	Comment Lines	Code Lines
Java	3	20	0	157
Groovy	3	23	9	140
Scala	3	32	9	127
Kotlin	3	23	9	136

Size Counter

Language	Disable Proguard (bytes)	Enable Proguard (bytes)
Java	1,228,376	772,571
Groovy	3,003,235	1,759,722
Scala	over 65536 methods	1,026,688
Kotlin	1,595,108	778,629

Method Counter

Language	Disable Proguard	Enable Proguard
Java	163,06	7,065
Groovy	46,791	23,775
Scala	over 65536 methods	12,180
Kotlin	23,236	7,193

Build Speed

Test on MacBook Pro (Retina, 15-inch, Mid 2014 & APPLE SSD SM0256F Media)

Gradle task: ./gradlew :app:clean :app:assembleDebug SBT task: sbt app/clean app/android:package

Language	Gradle Plugin	Spend (secs)	SBT	Spend (secs)
Java	2.1.0-rc1	≈ 7	0.13.11	≈ 9
Groovy	1.5.0	≈ 21	0.13.11	-
Scala	1.3.1	≈ 23	0.13.11	≈ 21
Kotlin	2.1.0-rc1	≈ 8	0.13.11	≈ 16

Coding Comparison

Find View

Java

TextView title = (TextView)view.findViewById(android.R.id.text1);

Groovy

def title = view.findViewById(android.R.id.text1) as TextView

Scala

val title = view.findViewById(android.R.id.text1).asInstanceOf[TextView]

Kotlin

With Kotlin Android Extensions enabled (no extra dependencies needed):

val title = view.text1

Note: as a fallback, one can use the more traditional cast-based approach:

val title = view.findViewById(android.R.id.text1) as TextView

OnClickListener

Java

button.setOnClickListener(new View.OnClickListener() {
    @Override
    void onClick(final View v) {
      //  do something
    }
})

Groovy

button.onClickListener = {
    //  do something
}

Scala

button.onClick((v: View) =>
    //  do something
)

Kotlin

button.setOnClickListener {
    //  do something
}

Callback

Java

public interface FindCallback {
    void onFinish(List<String> results, Exception e);
}
private void findCountries(FindCallback doneCallback) {
    try {
        //  a long time mission
        doneCallback.onFinish(results, null);
    } catch (Exception e) {
        doneCallback.onFinish(null, e);
    }
}
findCountries(new FindCallback(){
    void onFinish(List<String> results, Exception e){
      //  handle result
    }
});

Groovy

def findCountries(Closure doneCallback) {
    try {
        //  a long time mission
        doneCallback(results, null)
    } catch (e) {
        doneCallback(null, e)
    }
}
findCountries{ List<String> results, Exception e ->
  //  handle result
});

Scala

def findCountries(doneCallback: (ArrayBuffer[String], Exception) => Unit):Unit = {
    try {
        //  a long time mission
        doneCallback(results, null)
    } catch {
        case e: Exception => doneCallback(null, e)
    }
}
findCountries((names: ArrayBuffer[String], e: Exception) =>
  //  handle result
)

Kotlin

fun findCountries(doneCallback: (List<String>?, Exception?) -> Unit) {
    try {
        //  a long time mission
        doneCallback(results, null)
    } catch (e: Exception) {
        doneCallback(null, e)
    }
}
findCountries{ list, e ->
  //  handle result
}

Community Support

• Java Native Support
• Groovy Official Support
• Scala No Support
• Kotlin Official Support

Conclusion

The futher comparasion to be continue...