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Re: Lambda function that takes no parameter and returns String

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From	Arne Vajhøj <arne@vajhoej.dk>
Newsgroups	comp.lang.java.programmer
Subject	Re: Lambda function that takes no parameter and returns String
Date	Fri, 23 Jun 2017 22:18:30 -0400
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On 6/23/2017 10:15 PM, Arne Vajhøj wrote:
> On 6/23/2017 9:56 PM, Cecil Westerhof wrote:
>> I want to start with lambda functions. How would I write a lambda
>> function that does not take a parameter and returns a String? And how
>> do I ascribe that lambda function to a variable?
> 
> Example:
> 
> public class LambdaFun {
>      @FunctionalInterface
>      public static interface F {
>          public String get();
>      }
>      public static void test(F f) {
>          System.out.println(f.get());
>      }
>      public static void main(String[] args) {
>          test(() -> "one");
>          test(() -> "two");
>          test(() -> "three");
>          F four = () -> "four";
>          test(four);
>      }
> }

In this specific case you do not need to define your own functional
interface as Java comes with a usable one:

import java.util.function.Supplier;

public class LambdaFun2 {
	public static void test(Supplier<String> f) {
		System.out.println(f.get());
	}
	public static void main(String[] args) {
		test(() -> "one");
		test(() -> "two");
		test(() -> "three");
		Supplier<String> four = () -> "four";
		test(four);
	}
}

Arne

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Thread

Lambda function that takes no parameter and returns String Cecil Westerhof <Cecil@decebal.nl> - 2017-06-24 03:56 +0200
  Re: Lambda function that takes no parameter and returns String Arne Vajhøj <arne@vajhoej.dk> - 2017-06-23 22:15 -0400
    Re: Lambda function that takes no parameter and returns String Arne Vajhøj <arne@vajhoej.dk> - 2017-06-23 22:18 -0400

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