Auto-complete support for kotlin in Eclipse-neon I have imported a spring-boot + Kotlin project into Eclipse-Neon . But When I am trying to do auto-import or tool-tip help for definitions used inside the application , i am not getting it . I have searched on and found this link and this saying that no support is available . Please Help!

Gradle: checking for inadvertent transitive library use I have project P. P depends on library L1, and L1 depends on library T1. Now, an unsuspecting developer comes along and modifies P to include a direct dependency on T1. This works, since P has a transitive dependency on T1, therefore T1 is available for use. However, I would like Gradle to show me a report or warning that T1 should really be added as a direct dependency of P, otherwise the dependency graph isn't really correct: P uses T1 but does not depend on it explicitly. How can I do...

Android Library Module developed in Kotlin exported to Java Application causing Failed resolution of: Lkotlin/jvm/internal/Intrinsics I've developed an Android Library Module in Kotlin - tested it on a Kotlin project and it all works just fine. Using gradle's maven-publishing plugin, I've generated the aar files and uploaded them on a Maven Server, so latter I added the lib on a Android Java Application using compile 'groupartifactversion'. Library files seems to be recognized, however, when I attempt to start an activity existent on the Lib I get the following stacktrace: 05-12 142148.221 11735-11735/*****.*****.dev...

Android Library, Kotlin and Dagger2 I'm building an application that have two modules: the Core module, that is an Android Library (com.android.library) and the Application module (com.android.application). After I converted the Java files to Kotlin, the project is not compiling, giving me an error that the generated Dagger 2 files were not found (unresolved reference). But those files currently being generated under: ...core\build\generated\source\kapt\release{my\core\namespace}\DaggerBaseComponent.java What I'm...

Inject constructor and companion object I'm kind of new to Kotlin and I'm trying to Inject a value (in this example it is just an Int but in the real code it is a Provider class) What am I doing wrong here? and why is x is an unresolved reference?

class Test
@Inject constructor(
            private val x: Int) {

companion object {
    var y: Int = 0

    @BeforeClass @JvmStatic
    fun beforeClass() {
        y = x * 2
    }
}


}

Reconstruct N-ary Tree from List data class Node(val ID : Long, val name : String) I have an ordered list of the following three values (in order of appearance): ID, Name and Depth. 0000 : A : 0 0001 : B : 1 0002 : C : 2 0003 : D : 2 0004 : E : 1 0005 : F : 2 0006 : G : 1 0007 : H : 1 0008 : I : 2 Using this data set I wish to reconstruct the original N-ary tree as a Map, visualized below: A - B - C - D - E - F - G - H - I What is the best (most performant and/or most readable) way to accomplish this task?

Kotlin: Why does the !! operator generate null checks when compiling for the jvm? I am using https://javap.yawk.at/ to inspect Kotlin generated bytecode. I found that whenever the !! operator is used , a corresponding null check is generated. For example, for the following kotlin code: fun main(args: Array) { var a : Int? = null; println(a!!+2) } this code is generated: public final class MainKt { public static final void main(@NotNull final String[] args) {...

Kotlin: Superclass property not initialized in Derived class I have the following Kotlin Code: import java.util.* import kotlin.collections.HashSet open class Graph(open val n: Int) { val graph = List(n) {HashSet()} open fun addEdge(u: Int, v: Int) { graph[u].add(v) graph[v].add(u) } val numEdges: Int get() { return graph.asSequence() .map { it.size } .reduce { x, y -> x + y } } fun edgeSet() : HashSet { val result = HashSet()...

Modified method with new condition I have a next method: fun getTimeFromLastPinInput(): Long { return DateTime.now().millis - PreferenceRepository.getLastPinInputTime() } I want to add a next condition: if (DateTime.now().millis >= PreferenceRepository.getLastPinInputTime()) How i can modified my method correct?

Design patterns used in Kotlin Which design patterns can be used while developing application in Kotlin? Any examples? For ex. for java/android there is MVP or MVC.

Kotlin Android Library Module exported with gradle maven-publish plugin not adding dependencies I'm trying to export an Android Library Module developed in Kotlin using gradle's maven-publish plugin. aar file is successfully generated and exported however no dependency is added to it - at all, not even Kotlin ones. Below is the plugin configuration based on <a...

Using Kotlin class in Java: Cannot find symbol I have found this similar question regarding Android, but I am using plain Java with Maven as build tool. I think it is better to post a new question. I have created a Kotlin class to which I am trying to refer from Java class as MyKotlinClass.class. The Maven build fails. I have already added Kotlin plugin to maven: org.jetbrains.kotlin...

A function with generic return type Is it possible to have a function that returns a generic type? Something like: fun doSomething() : T { when { T is Boolean -> somethingThatReturnsBoolean() T is Int -> somethingThatReturnsInt() else -> throw Exception("Unhandled return type") } }

Inferring a generic type of Map in Kotlin Consider a Java method which infers its type by Java class as follows: public T readJson(Class c) throws IOException { This allows doing something like this: Map map = foo.readJson(Map.class); In java it will warn about unchecked cast, but it will work correctly. However in Kotlin, this will not be so easy, one could try using: foo.readJson(Map::class.java) However if Map will be required, it will not work: Type inference failed. Expected type mismatch. required Map found Map! I...

How to move b2d Body through static platform if button pressed I'm making platformer game. I have b2d Body - Player and b2d Body - Platform. I want player to stop colliding with platform when some button pressed. I tried B2dContactFilter but it didn't help because player is colliding when i want to fall down throught the platform. B2dContactListener didn't help to. I tried to set platform body not active, but i don't want to other bodies fall down to. Need help. Sorry for my English by the way. Thanks

How can I use Java &amp;quot;extends&amp;quot; with Generics in Kotlin? I have an interface called MvpPresenter: interface MvpPresenter { var view: VIEW? } and, I have a class called PresenterActivity: abstract class PresenterActivity : AppCompatActivity(), MvpView { @Inject lateinit var presenter: PRESENTER override fun onStart() { super.onStart() presenter.view = this // Type mismatch: Expected VIEW, Found PresenterActivity } } But, when I try to create a presenter class in which implements MvpPresenter: class...

Kotlin trasformation of objects to another objects http://cm08323.tmweb.ru/android/determinace/json/images.json I have some json to the server. My database class: @Entity data class Image(val url: String = "", val urlAnswer: String = "", val race: String = "") : DisplayableItem, Persistable Interface for api: interface ImagesAdi { @GET("android/determinace/json/images.json") fun getImages(): Single } ... class ImagesResponse(...

Android Studio Support for Kotlin When using Java on Android Studio I must often don't have to create files, I just type the name of the class I want to use and use "Intent Actions" to solve the problem and create the necessary file. The problem is, when using Kotlin, if I need, lets say an Interface, when I hit the Intent Action, Android Studio creates that Interface in the same file I'm working on, instead of providing a dialog for package selection as it does for Java. Any thoughts on how to fix this?

Comparing two optionals in Kotlin Consider a class with id field which might be null until stored in database: class IdableK : Comparable { private var id : Long? = null } I am trying to implement a compareTo method as follows: override fun compareTo(other: T): Int { if (id == null) { return -1; } if (other.id == null) { return 1; } return id!!.compareTo(other.id!!) } Is this a correct way of doing it? Would there be a simple way of doing it?

Proper way to get properties with Kotlin-script config for Gradle I have a property in gradle.properties: answer=42 Which is used in build.gradle: println "answer is ${answer}" Now I want to replace Groovy with Kotlin-script for Gradle configuring. How to access properties in a proper way? What I'm doing now is: build.gradle.kts: fun property(name: String) = properties[name] as String println("answer is " + property("answer")) Which does not seem to be very convinient. Thanks!

Android Cannot resolve symbol '?attr/selectableItemBackground' I got this error message Cannot resolve symbol '?attr/selectableItemBackground' Validates resource references inside Android XML files. And, I got a similar error for the above as well Cannot resolve symbol '@style/TextAppearance.AppCompat.Headline' Validates resource references inside Android XML files. Any pointer would be great! Thank you! It seems to be related to this <a...

Can / Should I add kotlinc.xml to my version control ignore file? Somewhere in the process of setting up a Java project in IntelliJ IDEA (2017.1.2) a file in the .idea/ directory called kotlinc.xml showed up. I do nothing with Kotlin, but the file is there with contents: This seems some generic configuration, but I can imagine some project-specific (and not just my-local-IDEA-specific) configuration of Kotlin is stored there. So, in general, can this file be ignored when sharing the project under version control (e.g. Git), i.e., not...

Dynamically evaluating templated Strings in Kotlin Suppose that I have the following piece of Kotlin code: fun main(args: Array) { val a = "test" println(args.first()) } If I pass in an argument $a, the output is going to be $a. As I understand it Kotlin takes care of String templates by generating the code for the output on compilation, presumably using a StringBuilder. Is there some way to evaluate Strings that aren't in the source code with regards to templates in their current context? String templates are very useful and...

Kotlin Inheritance I'm currently learning to split my messy code into DDD (note, learning) paradigm. The entities (IEntity, IUser) is domain layer is made up of interface, which then implemented at the Data layer (BaseEntity, User). Access to data is through the repository pattern. But as I defined for IUserRepository to return IUser, at the data layer I have to manually cast it User back to IUser to match the return signature. The code below works but how can I avoid the casting? Thank you. Domain layer...

Android Retrofit + SimpleXmlConverter with Empty entity I'm trying to request Restful api data from retrofit, with SimpleXmlConverter. But I got this error. org.simpleframework.xml.core.ConstructorException: Parameter 'comMsgHeader' does not have a match in class tylenol.common.model.retrofit.routelist.ServiceResult Sample XML Request 0 ... 0 .... And this is my data class written by kotlin. data class ServiceResult( val msgHeader: MsgHeader? = null, val msgBody: MsgBody? = null,...

unable to create ArrayList inside RealmObject subclass I have a class which is subclass of RealmObject, and I want to create inside that class arraylist which will be deserialized by gson, when I'm starting building project compile time error appears that Error:Type 'java.util.ArrayList' of field 'messages' is not supported here is my class open class MessageContainerObject : RealmObject() { @SerializedName("from") var from = "" @SerializedName("messages") var messages = ArrayList() class Test } if I remove the parent class...

Why is Gradle build of Kotlin source code pausing for ~3 secs &amp;quot;forcing System.gc()&amp;quot;? Every build takes an extra 3-4 seconds, pausing immediately after the log output prints the following. [LIFECYCLE] [org.jetbrains.kotlin.gradle.plugin.KotlinGradleBuildServices] Forcing System.gc() Why is it "forcing" this? How do I avoid this and speed up my build?

Kotlin: Nullable field with Non-nullable getter I am trying to implement non-nullable getter with nullable setter and nullable field. Field parent can be null, which means that the parent is this. If parent is not null, the parent is the parent value. Getter is not-nullable as it either returns this or parent Setter can set nullable value as it can remove the current parent. I tried this: @ManyToOne(fetch = FetchType.EAGER) @JoinColumn(name = "parent_id") var _parent: T? = null var parent: T get() = if (isParent) this as T else...

Animation set, shake effect I try to shake animation my view, i write this code, but It seems to me that it is possible to make it easier var animatorSet = AnimatorSet() var objectRotateAnimator = ObjectAnimator.ofFloat(shake, "rotation", -5f, 5f) objectRotateAnimator.apply { repeatMode = ValueAnimator.REVERSE repeatCount = ValueAnimator.INFINITE duration = 70 interpolator = LinearInterpolator() } var objectTranslateAnimator = ObjectAnimator.ofFloat(shake, "translate",...

How to not contact two Bodies without ContactFilter How to do this using ContactListener: Code for ContactFilter override fun shouldCollide(fixtureA: Fixture, fixtureB: Fixture): Boolean { return gameScreen.player.playerBody!!.linearVelocity.y < -3.5f || fixtureA.filterData.categoryBits or fixtureB.filterData.categoryBits != gameScreen.PLATFORM_BIT } Player shouldn't collide with platform if it's linear vlocity y < -3.5f You can answer in java.