Download - JDK 9, 10, 11 and Beyond: Delivering New Features …2011/09/10 · JDK 9: The Clean Up Starts JDK 9 was a significant change for Java – Deprecated APIs were removed for the first

© Copyright Azul Systems 2018


@speakjava azul.com

JDK 9, 10, 11 and Beyond: Delivering New Features in the JDK

Simon Ritter Deputy CTO, Azul Systems

1


JDK 9: Big And Small Changes

2


Java Platform Module System (JPMS) §  The core Java libraries are now a set of modules (JEP 220)

– 75 OpenJDK modules: 27 Java SE, 48 JDK – Oracle JDK: 14 additional JDK, 8 JavaFX, 2 Oracle specific

§  Most internal APIs now encapsulated (JEP 260) – sun.misc.Unsafe– Some can be used with command line options

3


jlink: The Java Linker (JEP 282)

4

Modular run-time image

… conf bin

jlink

$jlink--modulepath$JDKMODS\--addmodsjava.base–outputmyimage$myimage/bin/java–-list-modulesjava.base@9

lib


jlink: The Java Linker (JEP 282)

$jlink--module-path$JDKMODS:$MYMODS\--addmodscom.azul.zapp–-outputmyimage$myimage/bin/java–[email protected]@[email protected]@[email protected]@[email protected]


Moving Java Forward Faster


Java Platform Development §  Development of releases takes time

– JDK 6: 2 years and 2 months after JDK 5 – JDK 7: 4 years and 8 months after JDK 6 – JDK 8: 2 years and 8 months after JDK 7 – JDK 9: 3 years and 6 months after JDK 8

7


Migrating To A New Version §  Plenty of time to continue with previous release

– JDK 6: 2 years and 11 months of public JDK 5 updates – JDK 7: 1 year and 9 months of public JDK 6 updates – JDK 8: 1 year and 1 month of public JDK 7 updates

§  Also allows for stabilisation of new platform before migrating applications in production

8


The Java Platform Today

9

Stable

Secure

Free


OpenJDK: New Release Model §  A new version of the JDK will be released every six months

– March and September – Started this year with JDK 10 and JDK 11

§  OpenJDK development will be more agile – Previous target was a release every two years

§  Features will be included only when ready – Targeted for a release when feature complete

10


Long Term Support Releases §  Long term support for all releases is not practical

– One Long Term Support (LTS) release every three years §  JDK 8 has been classified as an LTS release

§ JDK 8 public updates stop in January 2019 for commercial users § Non-commercial users get updates until December 2020

§  Next LTS release is JDK 11 § JDK 9 and JDK 10 are feature releases § Updates for only six months

11


Which JDK Binary §  Traditional Oracle branded binary (java.oracle.com)

– Oracle Binary Code License (FoU restrictions) §  New OpenJDK binary (jdk.java.net)

– GPLv2 with CPE license (no restrictions) – Security and bug fix updates only for six months

§ Only until next JDK release § Two scheduled updates

– No overlap of updates for previous version

12


Converged Binaries

Oracle JDK

OpenJDK

Java SE

JDK 10 and earlier

Java SE

OpenJDK & Oracle JDK

JDK 11 and later


Converged Binaries (JDK 11) §  Some closed-source parts of the JDK will be open-sourced

– Flight recorder – Mission control ✔ – Others ✔

§  Other closed-source parts will be removed – Browser Plugin – Java Web Start – JavaFX

14


JDK 9 Onwards And Compatibility

15

"Clean applications that just depend on java.se should just work" - Oracle


JDK 9: The Clean Up Starts §  JDK 9 was a significant change for Java

– Deprecated APIs were removed for the first time § Six methods and one class § JDK 10 removed 1 package, 6 classes, 9 methods and 1 field

– Redundant features eliminated §  jhat tool, JVM TI hprof agent § Numerous deprecated GC options removed

– Significant command line changes § JDK 9 removed 187 -XX flags § JDK 10 removed 36 -XX flags

16


Housekeeping Will Continue §  More significant removals in JDK 11

– Applets, Browser Plugin, Web Start, JavaFX – java.se.ee meta-module

§ java.corba§ java.transaction§ java.activation§ java.xml.bind§ java.xml.ws§ java.xml.ws.annotation

§  More in the future – Nashorn deprecated, CMS garbage collector?

17


Compatibility Not Guaranteed §  New versions of Java may include breaking changes

– Anything for removal will be deprecated first – Minimum of one release warning

§ Could be only six months

18


Eliminating Confusion §  There will be an LTS release every three years

– This does NOT mean 3 years of free updates §  Oracle JDK (from JDK 11) can ONLY be used in production

with a commercial support contract – The only free JDK 11 and later will be OpenJDK binaries

§  To continue to receive free updates to the JDK you MUST update your JDK EVERY SIX MONTHS

§  JDK 8 can be used indefinitely for free – But without any further security patches and bug fixes

19


New JDK Update Schedule


The Java Platform Soon

21

Stable

Secure

Free

Choose two out of three


JDK 10


Local Variable Type Inference §  JEP 286

– Simple use cases

– Style guidelines available – Good (appropriate use of variable name)

– Poor

§  Infered type is PriorityQueue<Object>

23

varlist=newArrayList<String>();//infersArrayList<String>varstream=list.stream();//infersStream<String>

varstringList=List.of("a","b","c");

varitemQueue=newPriorityQueue<>();


JDK 10: JEPs §  JEP 307: Parallel Full GC for G1

– Still a full GC with potentially big pauses §  JEP 310: Application Class-Data Sharing

– Previous commercial Oracle feature §  JEP 317: Experimental Java-based JIT compiler (Graal) §  JEP 319: Root Certificates

– default set of root CA certificates §  JEP 296: Consolidate JDK forests into single repo

– Eight repos becomes one

24


JDK 10: JEPs §  JEP 316: Heap allocation on alternative devices (Intel)

–  NV-RAM with same semantics as DRAM

§  JEP 313: Remove javah tool – Same functionality through javac

§  JEP 304: Garbage Collector Interface (Red Hat) – Easier to add new algorithms (JVM internal)

§  JEP 312: Thread-Local Handshakes – Execute callbacks on threads without performing a global

VM safepoint

25


JDK 10: APIs §  73 New APIs

– List, Set, Map.copyOf(Collection)– Collectors

§ toUnmodifiableList§ toUnmodifiableMap§ toUnmodifiableSet

– Optional.orElseThrow()

26


JDK 10: Miscellaneous §  XMLInputFactory.newFactory() de-deprecated

(precated?) §  com.sun.security.auth package

– Six deprecated classes removed §  java.lang.SecurityManager

– One deprecated field and seven methods removed §  JVM now more Docker container aware

– Uses container CPU count and memory size – Namespace issues resolved (pids)

27


JDK 11


JDK 11 §  17 JEPs §  3 from outside Oracle

– JEP 318: Epsilon garbage collector (Red Hat) – JEP 315: Improve Aarch64 intrinsics (Red Hat) – JEP 331: Low overhead heap profiling (Google)

29


JDK 11: JEPs §  JEP 309: Dynamic Class-file constants

– Like invokedynamic but for class-file constants – Bootstrap method used at runtime, not compile time – Useful for compiler and language developers

§  JEP 328: Flight Recorder – Final piece of aligning OpenJDK and Oracle JDK

30


JDK 11: JEPs §  JEP 320: Remove CORBA and Java EE modules

– The power of a module system §  JEP 321: HTTP client

– HTTP/2 support – Incubating module from JDK 9 standardised

§  JEP 323: Local variable syntax for Lambda parameters – Extending JEP 286 in JDK 10 – (varx,vary)->x.process(y)

31


JDK 11: JEPs §  JEP 324: Key Agreement with Curve25519 and Curve448

– More efficient and secure than existing ECDH §  JEP 327: Unicode 10

– 8,518 new characters (seriously) – Bitcoin symbol, Nishu, Soyombo, Zanabazar Square – Long awaited (?) Colbert emoji

32


JDK 11: New APIs §  New methods but no new classes

– InputStreamnullInputStream()– WriternullWriter()– Pathof(String,String...)

33


Longer Term JDK Futures


OpenJDK Projects §  Amber

–  Simplifying syntax

§  Valhalla –  Value types and specialised generics

§  Loom –  Continuations and fibres

§  Metropolis –  The JVM re-written in Java

§  Panama –  FFI replacement for JNI

35


Project Amber §  JEP 286: Local variable type inference

– Delivered in JDK 10 §  JEP 323: Local variable syntax for Lambdas

– Will be delivered in JDK 11

36


Project Amber §  JEP 302: Lambda leftovers

– Single underscore for unused parameters §  JEP 326: Raw string literals (JDK 12)

– Use single backquote – `c:\Users\simon`– ```Astringwitha``init```

37


JEP 305: Pattern Matching §  Type test and switch statement support to start

38

Stringformatted;switch(obj){caseIntegeri:formatted=String.format("int%d",i);break;caseByteb:formatted=String.format("byte%d",b);break;caseLongl:formatted=String.format("long%d",l);break;caseDoubled:formatted=String.format("double%f",d);break;caseStrings:formatted=String.format("String%s",s);breakdefault:formatted=obj.toString();}


JEP 325: Switch Expressions (JDK 12)

39

intnumLetters;switch(day){caseMONDAY:caseFRIDAY:caseSUNDAY:numLetters=6;break;caseTUESDAY:numLetters=7;break;caseTHURSDAY:caseSATURDAY:numLetters=8;break;caseWEDNESDAY:numLetters=9;break;default:thrownewIllegalStateException("Huh?:"+day);};


JEP 325: Switch Expressions

intnumLetters=switch(day){caseMONDAY,FRIDAY,SUNDAY->6;caseTUESDAY->7;caseTHURSDAY,SATURDAY->8;caseWEDNESDAY->9;default->thrownewIllegalStateException("Huh?:"+day);};


Project Valhalla §  Java has:

– Primitives: for performance – Objects: for encapsulation, polymorphism, inheritance, OO

§  Problem is where we want to use primitives but can't – ArrayList<int> won't work – ArrayList<Integer> requires boxing and unboxing,

object creation, heap overhead, indirection reference

41


Project Valhalla §  Value types §  "Codes like a class, works like a primitive"

– Can have methods and fields – Can implement interfaces – Can use encapsulation – Can be generic – Can't be mutated – Can't be sub-classed

42


Project Loom §  Further work on making concurrent programming simpler

– Threads are too heavyweight §  Loom will introduce fibres

–  JVM level threads (remember green threads?) – Add continuations to the JVM – Use the ForkJoinPool scheduler – Much lighter weight than threads

§ Less memory § Close to zero overhead for task switching

43


Project Metropolis §  Run Java on Java

– Rewrite most of the JVM in Java §  Use the Graal compiler project as significant input §  Easier ports to new platforms

– Less native code to modify and compile §  Faster new features on front-end

– Easier to write Java than C++ §  Performance is an issue to be explored and resolved

– AOT compiler in JDK 9 is the start of this

44


Azul's Zulu Java


Zulu Java §  Azul’s free binary distribution of OpenJDK

– Passes all TCK tests §  JDK 6, 7, 8, 9,10 and 11 (EA) available §  Wider platform support:

– Intel 64-bit Windows, Mac, Linux – Intel 32-bit Windows and Linux – ARM 32 and 64-bit – PowerPC

46

www.azul.com/downloads/zulu


Summary


Java Continues To Evolve §  Faster Java releases

– Feature release every 6 months – Access to free updates is a consideration

§  Lots of ideas to improve Java – Value types, fibres, syntax improvements

§  Zulu Java has wide platform and JDK version support – Very reasonable cost for commercial support

48



@speakjava azul.com

Thank You!

Simon Ritter Deputy CTO, Azul Systems

49