Kotlin M5.2 IntelliJ IDEA 12.1 and Gradle.md

title	date	author	tags	keywords	categories	reward	reward_title	reward_wechat	reward_alipay	source_url	translator	translator_url
Kotlin M5.2: IntelliJ IDEA 12.1 and Gradle	2013-04-04 08:00:00 -0700	Andrey Breslav			官方动态	false	Have a nice Kotlin!			https://blog.jetbrains.com/kotlin/2013/04/kotlin-m5-2-intellij-idea-12-1-and-gradle/

Another update of Kotlin comes out today. Welcome Kotlin M5.2. 

Support for New IntelliJ IDEA

Koltin M5.2 supports (in fact, requires) the recently released IntelliJ IDEA 12.1 . The Kotlin IDE improvements include:

• Kotlin classes in the Class Hierarchy view. Just hit Ctrl+H on a class name to see its descendants and/or parents.
• Folding for imports (you don’t have to scroll through imports to get to your code any more).
• New UI for Kotlin library configuration: you can now control library names and location, and kotlin-runtime.jar is not copied to your project by default. It just works.
• Support for JavaScript-targeted modules is significantly improved.
• Optimizing imports on the fly: IDE Settings -> Editor -> Auto Import -> Optimize imports on the fly.
• New quick fixes: place the cursor on an error, and hit Alt+Enter.

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SAM Constructors

When using Java libraries, you can now create an instance of a SAM interface (one with a Single Abstract Method) by calling its name and passing a function literal. For example:

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SwingUtilities.invokeLater(Runnable { doItNow() })

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This works only for Java classes. In fact, it is not a part of the language, but a feature of how Java classes are loaded into Kotlin: we define a synthesized function

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fun Runnable(body: () -> Unit) = object : Runnable {
    override fun run() {
        body()
    }
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So whenever you import Runnable, the function is there too, and you can use it. This is the first chunk of SAM-conversion support for Java. Real SAM conversions will come soon, and you’ll be able to say simply

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SwingUtilities.invokeLater { doItNow(); }

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New Gradle Plugin

Starting with M5.2, in addition to the long-available Maven plugin, there’s a Gradle plugin for Kotlin from JetBrains. Here’s an example for building a Kotlin module with Gradle:

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buildscript {
  repositories {
    mavenCentral()
    maven {
      url 'http://repository.jetbrains.com/all'
    }
  }
  dependencies {
    classpath 'org.jetbrains.kotlin:kotlin-gradle-plugin:0.1-SNAPSHOT'
  }
}
 
apply plugin: "kotlin"
 
repositories {
  mavenCentral()
  maven {
    url 'http://repository.jetbrains.com/all'
  }
}
 
dependencies {
  compile 'org.jetbrains.kotlin:kotlin-stdlib:0.1-SNAPSHOT'
}

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More examples & docs can be found here .

Reminder: KAnnotator

Don’t forget that you now have KAnnotator at your service. Have a nice Kotlin!