Nashorn: JavaScript Running on Java VM (English)

3,535 views

Published on

This slide was used at Java Day Tokyo 2014.

Published in: Technology, News & Politics

Nashorn: JavaScript Running on Java VM (English)

  1. 1. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.1 JavaScript Running On JavaVM: Nashorn NISHIKAWA, Akihiro Oracle Corporation Japan
  2. 2. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.2 The following is intended to outline our general product direction. It is intended for information purposes only, and may not be incorporated into any contract. It is not a commitment to deliver any material, code, or functionality, and should not be relied upon in making purchasing decisions. The development, release, and timing of any features or functionality described for Oracle’s products remains at the sole discretion of Oracle.
  3. 3. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.3 Copyright © 2013, Oracle and/or its affiliates. All rights reserved. Agenda  Nashorn  Server Side JavaScript  Nashorn in the future
  4. 4. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.4 Nashorn
  5. 5. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.5 Nashorn JavaScript Engine running on Java VM
  6. 6. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.6 Nashorn JavaScript Engine running on Java VM
  7. 7. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.7 Backgrounds  Replacing Rhino – Concerns about security, performance, and so on  Proof of Concept for InvokeDynamic (JSR-292)  Atwood's law Any application that can be written in JavaScript will eventually be written in JavaScript.
  8. 8. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.8 Scope of Project Nashorn JEP 174  ECMAScript-262 Edition 5.1 compliant  Support for javax.script (JSR 223) API  Interaction between Java and JavaScript  Newly introduced command line tool (jjs)
  9. 9. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.9 Java VM Scripting Engine (Nashorn) Scripting API (JSR-223) JavaScript codeJava code Other runtime Other APIs jjs
  10. 10. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.10 $JAVA_HOME/bin/jjs $JAVA_HOME/jre/lib/ext/nashorn.jar
  11. 11. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.11 ECMAScript-262 Edition 5.1 compliant
  12. 12. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.12 Out of scope of Project Nashorn  ECMAScript 6 (Harmony) – Generators – Destructuring assignment – const, let, ...  DOM/CSS and related libraries – jQuery, Prototype, Dojo, …  Browser API and browser emulator – HTML5 canvas, HTML5 audio, WebGL, WebWorkers...
  13. 13. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.13 Examples
  14. 14. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.14 Invoke Nashorn from Java ScriptEngineManager manager = new ScriptEngineManager(); ScriptEngine engine = manager.getEngineByName("nashorn"); engine.eval("print('hello world')"); engine.eval(new FileReader("hello.js"));
  15. 15. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.15 Invoke Nashorn from Java Invoke script function from Java engine.eval("function hello(name) { print('Hello, ' + name)}"); Invocable inv=(Invocable)engine; Object obj= inv.invokeFunction("hello","Taro");
  16. 16. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.16 Invoke Nashorn from Java Implement an interface with script function engine.eval("function run(){ print('run() called’) }"); Invocable inv =(Invocable)engine; Runnable r=inv.getInterface(Runnable.class); Thread th=new Threads(r); th.start(); th.join();
  17. 17. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.17 Invoke Java/JavaFX from Nashorn print(java.lang.System.currentTimeMillis()); jjs -fx ...
  18. 18. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.18 Nashorn for Scripting Additional feature for scripting use  -scripting option  Here document  Back quote  String Interpolation ...
  19. 19. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.19 Nashorn Extensions
  20. 20. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.20 Nashorn Extensions The following topics are covered in this session.  How to get references of Java type  How to access properties of Java objects  Relationship among Lambda, SAM, and Script function  Scope and context
  21. 21. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.21 Java type
  22. 22. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.22 How to get references of Java type Expression in Rhino (This expression is valid in Nashorn) var hashmap=new java.util.HashMap(); Or var HashMap=java.util.HashMap; var hashmap=new HashMap();
  23. 23. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.23 How to get references of Java type Recommended expression in Nashorn var HashMap=Java.type('java.util.HashMap'); var hashmap=new HashMap();
  24. 24. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.24 Java.type Class or Package? java.util.ArrayList java.util.Arraylist
  25. 25. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.25 Java Array Expression in Rhino var intArray= java.lang.reflect.Array.newInstance( java.lang.Integer.TYPE, 5); var Array=java.lang.reflect.Array; var intClass=java.lang.Integer.TYPE; var array=Array.newInstance(intClass, 5);
  26. 26. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.26 Java Array Expression in Nashorn var intArray=new(Java.type("int[]"))(5); var intArrayType=Java.type("int[]"); var intArray=new intArrayType(5);
  27. 27. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.27 Access properties of Java objects
  28. 28. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.28 Using getter and setter var HashMap=Java.type('java.util.HashMap'); var map=new HashMap(); map.put('size', 2); print(map.get('size')); // 2
  29. 29. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.29 Directly var HashMap=Java.type('java.util.HashMap'); var map=new HashMap(); map.size=3; print(map.size); // 3 print(map.size()); // 1
  30. 30. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.30 Using Associative Array var HashMap=Java.type('java.util.HashMap'); var map=new HashMap(); map['size']=4; print(map['size']); // 4 print(map['size']()); // 1
  31. 31. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.31 Lambda, SAM, and Script function
  32. 32. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.32 Lambda, SAM, and Script function Nashorn converts a script function to a lambda object or any SAM interface implementing object automatically. var timer=new java.util.Timer(); timer.schedule( function() { print('Tick') }, 0, 1000); java.lang.Thread.sleep(5000); timer.cancel();
  33. 33. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.33 Lambda, SAM, and Script function Any Java object which is an instance of lambda type can be treated like a script function. var JFunction= Java.type('java.util.function.Function'); var obj=new JFunction() { // x->print(x*x) apply: function(x) { print(x*x) } } print(typeof obj); //function obj(9); // 81 like Script function
  34. 34. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.34 Scope and Context
  35. 35. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.35 Scope and Context load and loadWithNewGlobal  load – Load scripts in the same global scope. – If same name variables are in the original scripts and loaded scripts, Corruption of each variable may happen.  loadWithNewGlobal – Load scripts in another global scope newly created. – Even if same name variables are in the original scripts and loaded scripts, Corruption of each variable may not happen.
  36. 36. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.36 Scope and Context ScriptContext contains one or more Bindings each associated each jsr223 "scope". ScriptContext ctx=new SimpleScriptContext(); ctx.setBindings(engine.createBindings(), ScriptContext.ENGINE_SCOPE); Bindings engineScope= ctx.getBindings(ScriptContext.ENGINE_SCOPE); engineScope.put("x", "world"); engine.eval("print(x)", ctx);
  37. 37. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.37 Scope and Context Using with clause and JavaImporter with(new JavaImporter(java.util, java.io)){ var map=new HashMap(); //java.util.HashMap map.put("js", "javascript"); map.put("java", "java"); print(map); .... }
  38. 38. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.38 Others  Convert between Java array and JavaScript array – Java.from – Java.to  Extend Java class and access super-class – Java.extend – Java.super and so on...
  39. 39. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.39 Server Side JavaScript
  40. 40. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.40 Java EE for Next Generation Applications Deliver HTML5, Dynamic and Scalable Applications WebSockets Avatar
  41. 41. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.41 Evolution of Web application architecture Request-Response and Multi-page application Java EE/JVM Presentation (Servlet/JSP) Business Logic Backend ConnectivityBrowser
  42. 42. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.42 Evolution of Web application architecture Use Ajax (JavaScript) Java EE/JVM Connectivity (REST, SSE) Presentation (Servlet/JSP, JSF) Business Logic Backend ConnectivityBrowser JavaScript
  43. 43. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.43 Modern Web application architecture Rather connectivity than Presentation – Single Page Application Java EE/JVM Connectivity (WebSocket, REST, SSE) Presentation (Servlet/JSP, JSF) Business Logic Backend ConnectivityBrowser View Controller JavaScript
  44. 44. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.44 How about Node.js?
  45. 45. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.45 Mobile-enabled existing services with Node.js Node.js JavaScript REST SSE WebSocket Browser View Controller JavaScript
  46. 46. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.46 How about Node.js on JVM?
  47. 47. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.47 Mobile-enabled existing services with Node Node running on Java VM Java EE/JVM Node Server Business Logic Backend Connectivity Client JavaScriptBrowser View Controller JavaScript
  48. 48. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.48 Avatar.js
  49. 49. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.49 Avatar.js Old name is "node.jar"  Able to use almost all of modules available on Node.js – Express, async, socket.io, ...  Some modules are required to modify. – Automatically recognize modules downloaded with npm.  Pros. – Leverage node programming model – Leverage existing Java assets, knowledge, and tools
  50. 50. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.50 Avatar.js = Node + Java Leverage Java technologies including Threads JavaJavaScript com.myOrg.myObj java.util.SortedSet java.lang.Thread require('async') postEvent Node App
  51. 51. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.51 Avatar
  52. 52. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.52 Avatar Server side JavaScript services framework  Provide data transmission features via REST, WebSocket, and Server Sent Event (SSE)  Leverage event-driven programming model and programming modules of Node.js  Integrate with Enterprise Features (Java EE)
  53. 53. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.53 *.html *.js *.css HTTP Application Services Avatar Modules Node Modules Avatar.js Avatar Runtime Avatar Compiler Server Runtime (Java EE) JDK 8 / Nashorn Application Views REST/WebSocket/SSE Avatar (Avatar EE) Change Notification Data
  54. 54. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.54 HTTP REST/WebSocket/SSE Avatar Compiler Application Views *.html *.js *.css Application Services Avatar Modules Node Modules Avatar.js Avatar Runtime Server Runtime (Java EE) JDK 8 / Nashorn Architecture (Server Side) Change Notification Data
  55. 55. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.55 Avatar Service Java JavaScript HTTP Load Balancer Services Shared State Services Services Change Notification Data
  56. 56. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.56 Avatar Runtime Server Runtime (Java EE) Avatar Modules Node Modules Avatar.js *.html *.js *.css Application Services JDK 8 / Nashorn Architecture (Client Side) Change Notification Data HTTP REST/WebSocket/SSE Application Views Avatar Compiler
  57. 57. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.57 Avatar and Avatar.js progress steadily.
  58. 58. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.58 Nashorn in the future
  59. 59. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.59 Nashorn in the future  Bytecode Persistence (JEP 194) http://openjdk.java.net/jeps/194  Optimistic Typing  Others
  60. 60. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.60 Summary
  61. 61. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.61 Key takeaways  Nashorn – Tightly integrated with Java – Pay attention to different expression when migrating artifacts from Rhino to Nashorn – Progress steadily (performance improvement, new features, compliant against new standards)  Server Side JavaScript – Avatar.js and Avatar are on-going. – Please feedback!
  62. 62. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.62 Appendix
  63. 63. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.63 Source code walk through Shell jjs uses mainly. Compiler generates classes (bytecode) from sources. Scanner Create tokens from sources. Parser Create AST/IR from tokens. IR Elements of scripts Codegen Create script class bytecode from AST/IR Objects Runtime elements (Object, String, Number, Date, RegExp) Scripts Classes including codes for scripts Runtime Runtime tasks Linker Binds callees on runtime based on JSR-292 (InvokeDynamic) Dynalink Searching for best methods (available across languages)
  64. 64. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.64 Nashorn Documents http://wiki.openjdk.java.net/display/Nashorn/Nashorn+Documentation  Java Platform, Standard Edition Nashorn User's Guide http://docs.oracle.com/javase/8/docs/technotes/guides/scripting/nash orn/  Scripting for the Java Platform http://docs.oracle.com/javase/8/docs/technotes/guides/scripting/  Oracle Java Platform, Standard Edition Java Scripting Programmer's Guide http://docs.oracle.com/javase/8/docs/technotes/guides/scripting/prog_ guide/
  65. 65. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.65 Nashorn http://openjdk.java.net/projects/nashorn/  OpenJDK wiki – Nashorn https://wiki.openjdk.java.net/display/Nashorn/Main  Mailing List nashorn-dev@openjdk.java.net  Blogs – Nashorn - JavaScript for the JVM http://blogs.oracle.com/nashorn/ – Nashorn Japan https://blogs.oracle.com/nashorn_ja/
  66. 66. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.66 Avatar.js  Project Page https://avatar-js.java.net/  Mailing List users@avatar-js.java.net
  67. 67. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.67 Avatar  Project Page https://avatar.java.net/  Mailing List users@avatar.java.net
  68. 68. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.68
  69. 69. Copyright © 2014, Oracle and/or its affiliates. All rights reserved.69

×