As Velhas Novas do Java 7

Transcript

1. Java 7 as velhas novas do

2. Java 6: Dec 2006 Java 7: Jul 2011 Java 8:

   Mar 2014 História

3. Lambdas, Jigsaw, e parte do Project Coin foram dropados do

   Java 7

4. Agenda • Diamond Operator • Strings em Switch’s • Automatic

   Resource Management • Numeric Literals com Underscores • Exception Handling (multi-catch) • NIO 2.0 • Fork and Join • invokedynamic

5. Diamond Operator // java 6 Map<String, List<String>> list6 = 


   new TreeMap<String, List<String>>(); // java 7 Map<String, List<String>> list7 = new TreeMap<>();

6. String em Switch’s // java 6 AnEnum a = AnEnum.A;

   switch (a) { case A: doSomethingWhenA(); break; // … }

7. String em Switch’s // java 7 String b = "b";

   switch(b) { case "b": doSomethingWhenB(); break; // … }

8. Automatic Resource Management // java 6 BlahResource resource; try {

   resource = new BlahResource(); resource.doSomething(); } catch (Exception e) { log.error( “Maoeee”, e ); } finally { try { resource.close(); } catch (BlahResourceException e) { log.error( “Ah haee”, e ); } }

9. Automatic Resource Management // java 7 try (BlahResource resource =

   new BlahResource()) { resource.doSomething(); } catch (Exception e) { log.error( “Maoeee”, e ); }

10. Numeric Literals // java 6 int thousand = 1000; //

    java 7 int thousand = 1_000;

11. Exception Handling // java 6 try { oneThousandCheckedExceptionsLater(); } catch

    (ExceptionOne e) { log.error(“Erro: ", e); } catch (ExceptionTwo e) { log.error(“Erro: ", e); } catch (ExceptionThree e) { log.error(“Erro: ", e); }

12. Exception Handling // java 7 try { oneThousandCheckedExceptionsLater(); } catch

    (ExceptionOne | ExceptionTwo | ExceptionThree e) { log.error(“Erro:”, e); }

13. NIO 2.0 • Path & Paths • Files • FileSystems

    • WatchService

14. Fork and Join • Dividir para conquistar • ForkJoinTask &

    ForkJoinPool

15. incokedynamic • Recurso da JVM para suportar melhor linguagens com

    tipagem dinâmica • java.lang.invoke

16. PROTIPS™

17. None

18. GRÁTIS NA LOJA KINDLE!

19. Bom e velho Javadoc ☕️

20. Dúvidas?

21. Thanks https://speakerdeck.com/caarlos0/as-velhas-novas-do-java-7