Java10 and 11

Java10 and 11

1. 1. Java 10まとめと、どうなる Java 11 2018/5/26 JJUG CCC 2018 Spring きしだ なおき
2. 2. About me •  Naoki Kishida •  LINE Fukuoka •  @kis
3. 3. Agenda •  New Release Model •  About JDK 10 •  About JDK 11 •  About Java Support
4. 4. New Release Model
5. 5. 6-monthly release •  Oracle had announced they will release Java every 6 months at 2017/9/6
6. 6. Java new release cycle. •  Feature release every 6 months –  March and September(春分の⽇/秋分の⽇) •  Maintenance release every 3 months –  April and July for March release –  October and January for September release •  Long Term Support every 3 years –  The first LTS is for JDK 11 •  Oracle JDK will be for only Oracle Customer –  Use OpenJDK instead.
7. 7. Version number •  2018/03 Feature release JDK10 •  2018/04 Maintenance release JDK10.0.1 •  2018/07 Maintenance release JDK10.0.2 •  2018/09 Feature release JDK11 LTS •  2018/10 Maintenance release JDK11.0.1 LTS •  2019/01 Maintenance release JDK11.0.2 LTS
8. 8. Java SE 8 support is extended •  Oracle has extended Java SE 8 support at least until 2019/1 •  It is available for the personal use until 2020/12 •  Java SE 8 support will finish after 3 months of JDK 11 release. •  We should move to JDK 11 by 2019/1 http://www.oracle.com/technetwork/jp/java/eol-135779-ja.html
9. 9. Desktop technology •  Applet and Web Start is no longer supported after JDK 11 •  JavaFX will not be bundled with JDK11 – So far OpenJDK had not bundled JavaFX •  AWT and Swing will be supported – There are many commits for JDK 11
10. 10. About JDK 10
11. 11. Java 10 JEPs •  286 Local-Variable Type Inference •  296 Consolidate the Repository •  304 GC Interface •  307 Paralell Full GC for G1 •  310 Application Class-Data Sharing •  312 Thread-Local Handshakes •  313 Remove javah •  314 Additional Unicode Language-Tag Extensions •  316 Heap Allocation on Alternative Momory Devices •  317 Experimental Java-Based JIT Compiler •  319 Root Certificates •  322 Time-Based Release Versioning
12. 12. 286: Local-Variable Type Inferences •  var list = new ArrayList<String>() •  `var` is not a keyword – but a special type •  We can use `var` as a variable name •  We can use `var` as a method name •  We can not use `var` as a class name
13. 13. Usage for `var` •  var m = new Object() {
 int twice(int x) {
 return x * 2;
 }
 };
 print(m.twice(3));
14. 14. 304: Garbage-Collector Interface •  GC is modularized. •  There are many GCs that will come. – Epsilon GC – ZGC – Shenandoah •  Not to control GC by user code
15. 15. 317: Experimental Java-Based JIT Compiler •  Project Metoropolis – java-on-java •  We can write JVM even with Scala? – There is a possibility.
16. 16. 307: Parallel Full GC for G1 •  G1GC had been the default GC on JDK 9 •  Full GC for G1 was not parallel. •  Until JDK 8, Parallel GC was the default •  To smooth migration, Full GC for G1GC also parallelize. •  But full GC should not occur. – Ideally, it has no effect for us.
17. 17. 310: Application Class-Data Sharing •  CDS for system class is introduced in JDK 5 •  Share class data between multiple JVM on the same machine – startup performance – reduce the resource footprint •  JDK 10 allow to use CDS for application class
18. 18. 312: Thread-Local Handshakes •  JVM can stop an individual thread – stop not just all thread
19. 19. 314: Additional Unicode Language-Tag Extentions •  Enhance java.util.Locale •  additional Unicode extensions of BCP 47 language tag – currency type – the first day of the week – region override – time zone
20. 20. 316: Heap Allocation on Alternative Memory Devices •  Now we can use non-volatile RAM(不 揮発性メモリ) such as 3D XPoint •  This will enable the JVM to use different types of memory system
21. 21. 319: Root Certificates •  OpenJDK doesnʼt have Root Certificates so far •  Oracle JDK have had it. •  To smooth migration, OpenJDK have had it.
22. 22. API Changes •  java.io.Reader – long transferTo(Writer) •  java.lang.mainagement.RuntimeMXBe an – long getPid() •  java.util.List/Map/Set – copyOf(Collection) •  java.util.stream.Collectors – toUnmodifiableList/Set/Map
23. 23. Docker aware •  Until JDK 9, JVM use the platform CPU count/Memory size even if it is running on Docker. •  JDK 10, JVM can use Docker setting for CPU count/ Memory size if it is running on Docker. •  VM Options –  -XX:InitialRAMPercentage –  -XX:MaxRAMPercentage –  -XX:MinRAMPercentage
24. 24. Other Changes •  Kerberos configuration file krb5.conf include *.conf in INCLUDEDIR •  -d32 and –d64 has been removed •  new JavaDoc tag. {@summary} •  policytool has been removed •  XMLInputFactory.newFactory() has been “de-deplicated” – it had been deplicated by mistake.
25. 25. About JDK 11
26. 26. Java 11 JEPs •  309 Dynamic Class-File Constants •  318 Epsilon: A No-Op Garbage Collector •  320 Remove the Java EE and CORBA Modules •  321 HTTP Client(Standard) •  323 Local-Variable Syntax for Lambda Parameters •  324 Key Agreement with Curve25519 and Curve448 •  327 Unicode 10 •  328 Flight Recorder •  329 ChaCha20 and Poly1305 Cryptographic Algorithms •  330 Launch Single-File Source-Code Programs
27. 27. Expected JEPs for JDK11 •  326 Raw String Literals •  325 Switch Expressions •  181 Nest-Based Access Control
28. 28. Launch Single-File Source-Code Programs •  java Hello.java •  Shebang – #! /usr/bin/java –source 10 – chmod +x hello – ./hello
29. 29. Raw String Literals •  var sql = ```select NAME
 from MEMBER
 where id=1``` •  How to address indent
30. 30. Switch Expressions •  Now `switch` is a statement •  int i;
 switch (s) {
 case “start”:
 case “begin”:
 i = 0;
 break;
 case “end”:
 i = 1;
 break;
 default:
 i = 2;
31. 31. Switch Expressions •  int i = switch (s) {
 case “start”,“begin”-> 0;
 case “end” -> 1;
 default -> 2;
 }
32. 32. Local-Variable Syntax for Lambda Parameters •  list.map(s -> s.toUpperCase())
 .collect(toList()) •  list.map((var s) -> s.toUpperCase())
 .collect(toList())
33. 33. HTTP Client(Standard) •  Guraduate the incubate •  var client HttpClient.newHttpClient();
 var url = URI.create(url);
 var req = HttpRequest.newBuilder(uri).build();
 HttpResponse<String> res = client.send(
 req, HttpResponse.BodyHandlers.ofString(
 Charset.forName(“utf-8”));
 return res.body();
34. 34. Epsilon: A No-Op Garbage Collector •  Do nothing! •  For evaluate GC performance
35. 35. Remove the Java EE and CORBA Modules •  No one uses CORBA! •  The size is large •  Removing them, JDK will be smaller
36. 36. Flight Recorder •  Logging the performance •  Now it is an open source
37. 37. Unicode 10 •  Support Unicode 9 and Unicode 10
38. 38. Nestmate •  To address inner class accesivility •  Valhalla!
39. 39. Java 11でのAPI追加 •  String – repeat – lines – isBlank – strip/stripLeading/stripTrailing
40. 40. String •  repeat •  isBlank •  lines •  strip/stripLeading/stripTrailing
41. 41. Predicate::not •  lines.filter(s -> !s.isEmpty()) → lines.filter(Predicate.not(String::isEmp ty))
42. 42. Files •  String Files.read(Path) •  Path FIles.write(Path, String) •  Files.isSameContent(Path, Path)
43. 43. ArrayIndexOutOfBoundsException •  jshell> new int[]{}[0] | java.lang.ArrayIndexOutOfBoundsException thrown: 0 | at (#1:1) -> jshell> new int[]{}[0] | Exception java.lang.ArrayIndexOutOfBoundsException: Index 0 out of bounds for length 0 | at (#8:1)
44. 44. How about Stream#toList？ •  modifiable? unmodifible? •  What order? •  “it nulls a property of the Stream API we have take time to keep. The whole Stream API doesn't depends on the Collection API”
45. 45. About Java Support
46. 46. Oracle JDK •  Same as the current support •  Very expensive for web servicer •  100 servers on AWS -> 1おくえん
47. 47. OpenJDK •  Official publishment says it has only 6 months support for each JDK release. No LTS •  Mark Reinhold said OpenJDK will have LTS – but not on the web site yet – LTS support is for 3 years. No overlap.
48. 48. AdoptOpenJDK •  Project by London JUG •  IBM suponsered •  Provide pre-build JDK •  LTS support for 4 years
49. 49. Zulu •  Provided by Azul System •  Free to download and use •  Enterprise support – 100 servers $28,750/year – unlimited servers $258,750/year
50. 50. Support the new era after Heisei •  Start to support the new era as NewEra •  JDK12 will release 2019/3 •  The new era will release early 2019/4 •  JDK maintenance release will be late 2019/4 – JDK 12.0.1 •  The new era will start 2019/5
51. 51. Summary •  がんばろ