Java - Lambdas: Difference between revisions

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Line 2: Line 2:
==Syntax==
==Syntax==
<source lang="java">
<source lang="java">
  @Component
  (String first, String second)
public class WelcomeService {
   -> Integer.compare(first.length(), second.length())
  //Bla Bla Bla
}
@RestController
public class WelcomeController {
  @Autowired
  private WelcomeService service;
  @RequestMapping("/welcome")
   public String welcome() {
    return service.retrieveWelcomeMessage();
  }
}
</source>
</source>



Revision as of 15:28, 18 October 2019

Lambdas

Syntax

<source lang="java">

(String first, String second)
  -> Integer.compare(first.length(), second.length())

</source>

Declaration

Use

Use Functional Interfaces https://docs.oracle.com/javase/8/docs/api/java/lang/FunctionalInterface.html They have only one method

Questions & Answers

concrete methods interface methode default implementee = interface fonctionnelle

  • if a class implements two interfaces with the same name method: multiplicatedefaulterror

je ne peux utiliser que les variables finales dans une lambda expression lambda n'est pas thread safe

Loops

INTERNAL: nouveau foreach ==> je ne veux pas savoir ce ton implementation: fais le avec la lambda que je te donne EXTERNAL: ancien foreach, a BANNIR