Java.lang.NoSuchMethodError: main when starting HelloWorld with the Eclipse Scala plugin

Question

I just played with Scala and installed the Eclipse plugin as described at http://www.scala-lang.org/node/94 , but after entering the Hello World example and configuring the launch configuration as described, I get the following error :

Exception in thread "main" java.lang.NoSuchMethodError: main

For reference code

package hello

object HelloWorld extends Application {
  println("Hello World!")
}

I worked a bit with the obvious solutions (adding the main method, adding a singleton object with the main method), but I'm obviously doing something wrong.

Can someone get my test case to work or indicate what I'm doing wrong?

Answer 1

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Answer 2

:

package hello

class HelloWorld extends Application {
  Console.println("Hello World!")
}

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Answer 3

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Answer 4

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package hello

object HelloWorld {
  def main(args:Array[String]) {
    println("Hello World!")
  }
}

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Answer 5

. :

• Run- > Run Configuration
• JavaApplication, (, hello.HelloWorld)

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Answer 6

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Answer 7

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Answer 8

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Answer 9

Netbeans ~ , . Eclipse 3.4 + Scala Plugin 2.7.5 Final . Eclipse 3.4, Scala 2.7.5, .. Scala? .. → Scala? , , .

Answer 10

If you are using the latest version of scala (2.9. *), You should use

object HelloWorld extends App {
  println("Hello World!")
}

An application, not an application. The application was in 2.8 or 2.7 way. This is the only problem - this is another question.

Answer 11

The simple answer is: if you are using (NetBeans OR Eclips) just restart the program yet Move the class to another class, which may help