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![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.11 JsonGenerator generator = Json.createGenerator(out); generator.writeStartObject(); generator.writeStartArray("phones"); generator.writeStartObject(); generator.write("name", "iPhone"); generator.write("model", "5"); generator.writeEnd(); generator.writeEnd(); generator.write("total", 1); generator.writeEnd(); generator.close(); JSR 353: JSON Processing 1.0 Streaming API {“phones”:[{“name”:”iPhone”,”model”:”5”], {“total”:1}](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-11-2048.jpg)
![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.12 { "firstName": "John", "lastName": "Smith", "age": 25, "phoneNumber": [ { "type": "home", "number": "212 555-1234" }, { "type": "fax", "number": "646 555-4567" } ] } JsonParser p = Json.createParser(…); JsonParser.Event event = p.next(); // START_OBJECT event = p.next(); // KEY_NAME event = p.next(); // VALUE_STRING String name = p.getString(); // "John” JSR 353: JSON Processing 1.0 Streaming API](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-12-2048.jpg)
![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.13 {“phones”:[{“name”:”iPhone”,”model”:”5”], {“total”:1} JsonObject jsonObject = Json.createObjectBuilder() .add(“phones", Json.createArrayBuilder() .add(Json.createObjectBuilder() .add("name", “iPhone") .add(“model", 5) .add("Total", 1).build(); JSR 353: JSON Processing 1.0 Object Model API](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-13-2048.jpg)
![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.25 JSR 236: Concurrency Utilities for Java EE 1.0 ContextService // Within your servlet or EJB method… @Resource ContextService ctxSvc; void businessMethod() { Runnable runnableTask= new Runnable() { void run() {// Interact with a database… use component's security}} // Wrap with the current context Runnable runnableTaskWithCtx= (Runnable) ctxSvc.createContextObject(runnableTask, new Class[]{Runnable.class} // Store the runnablewith context somewhere and run later store.putIt(runnableTaskWithCtx);](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-25-2048.jpg)
![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.28 Servlet 3.1 public class TestServlet extends HttpServlet protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { ServletInputStream input = request.getInputStream(); byte[] b = new byte[1024]; int len = -1; while ((len = input.read(b)) != -1) { . . . } } } Non-blocking I/O Traditional](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-28-2048.jpg)
![Copyright © 2012, Oracle and/or its affiliates. All rights reserved.30 Servlet 3.1 @Override public void onDataAvailable() { try { StringBuilder sb = new StringBuilder(); int len = -1; byte b[] = new byte[1024]; while (input.isReady() && (len = input.read(b)) != -1) { String data = new String(b, 0, len); System.out.println("--> " + data); } } catch (IOException ex) { . . . } } . . . Non-blocking read](https://image.slidesharecdn.com/javaee7-140625023257-phpapp01/75/Java-EE7-30-2048.jpg)
Uploaded byJay Lee
Java EE7
The document discusses new features in Java EE 7 including support for WebSockets, JSON processing, RESTful web services, batch applications, and concurrency utilities. Key enhancements include simplified APIs, support for asynchronous programming, and improved developer productivity and integration capabilities. The specifications covered include JSRs 356, 353, 339, 344, 236, and 352.
Java EE7
- 1. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.1
- 2. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.2 The Java EE 7 Platform Productivity++ and HTML5 이창재 Senior Architect blogs.oracle.com/jaylee
- 3. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.3 Java: Broadest Industry Adoption 9,000,000 자바 개발자 Java EE Compliant 한 18 개의 어플리케이션 서버
- 4. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.4 Java EE 7 Platform 2013년 6월 12일
- 5. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.5 Java EE 7 메인 테마 Batch Concurrency 좀 더 단순화 된 JMS API POJO 를 위한 좀 더 다양한 annotation 지원 코드 단순화 더욱 쉬워진 통합 개발자 생산성 WebSockets JSON Servlet 3.1 NIO REST 기업의 요구사항 충족 Java EE 7
- 6. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.6 Top Ten Features in Java EE 7 1. WebSocket client/server endpoints 2. JSON Processing 3. JAX-RS Client API 4. JSF 2.2 5. Concurrency Utilities 6. Servlet 3.1 7. Simplified JMS API 8. Batch Applications 9. @Transactional and @TransactionScoped 10. Default Resources
- 7. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.7 JSR 356: Java API for WebSocket 1.0 Server, Client WebSocket Endpoint – Annotation: @ServerEndpoint, @ClientEndpoint – Programmatic: Endpoint 라이프 사이클 지원(@OnOpen,@OnClose) 패키징 및 배포(표준 JavaEE) @ServerEndpoint(“/chat”) public class ChatServer { @OnMessage public void chat(String m) { . . . } }
- 8. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.8 JSR 356: Java API for WebSocket 1.0 @ServerEndpoint("/chat") public class ChatBean { static Set<Session> peers = Collections.synchronizedSet(…); @OnOpen public void onOpen(Session peer) { peers.add(peer); } @OnClose public void onClose(Session peer) { peers.remove(peer); } . . . Chat Server
- 9. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.9 JSR 356: Java API for WebSocket 1.0 . . . @OnMessage public void message(String message) { for (Session peer : peers) { peer.getRemote().sendObject(message); } } } Chat Server (계속)
- 10. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.10 JSR 353: JSON Processing 1.0 JSON 파싱 및 생성을 위한 API Streaming API – 저수준 – XML 의 StAX API 와 유사 Object Model API – 단순, 좀 더 간편해진 고수준의 API – XML 의 DOM API 와 유사
- 11. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.11 JsonGenerator generator = Json.createGenerator(out); generator.writeStartObject(); generator.writeStartArray("phones"); generator.writeStartObject(); generator.write("name", "iPhone"); generator.write("model", "5"); generator.writeEnd(); generator.writeEnd(); generator.write("total", 1); generator.writeEnd(); generator.close(); JSR 353: JSON Processing 1.0 Streaming API {“phones”:[{“name”:”iPhone”,”model”:”5”], {“total”:1}
- 12. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.12 { "firstName": "John", "lastName": "Smith", "age": 25, "phoneNumber": [ { "type": "home", "number": "212 555-1234" }, { "type": "fax", "number": "646 555-4567" } ] } JsonParser p = Json.createParser(…); JsonParser.Event event = p.next(); // START_OBJECT event = p.next(); // KEY_NAME event = p.next(); // VALUE_STRING String name = p.getString(); // "John” JSR 353: JSON Processing 1.0 Streaming API
- 13. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.13 {“phones”:[{“name”:”iPhone”,”model”:”5”], {“total”:1} JsonObject jsonObject = Json.createObjectBuilder() .add(“phones", Json.createArrayBuilder() .add(Json.createObjectBuilder() .add("name", “iPhone") .add(“model", 5) .add("Total", 1).build(); JSR 353: JSON Processing 1.0 Object Model API
- 14. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.14 JSR 339: Java API for RESTful Web Services 2.0 클라이언트 API 비동기 처리 지원 – Server and Client Message Filters 와 Entity Interceptors Common Configuration
- 15. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.15 JSR 339: Java API for RESTful Web Services 2.0 // Get instance of Client Client client = ClientBuilder.newClient(); // Get customer name for the shipped products String name = client.target(“../orders/{orderId}/customer”) .resolveTemplate(”orderId", ”10”) .queryParam(”shipped", ”true”) .request() .get(String.class); Client API
- 16. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.16 JSR 339: Java API for RESTful Web Services 2.0 URL url = new URL("http://. . ./orders/“ + orderId + “/customer”); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setRequestMethod("GET"); conn.setDoInput(true); conn.setDoOutput(false); BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream())); String line; while ((line = br.readLine()) != null) { //…… } Client API - before
- 17. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.17 JSR 339: Java API for RESTful Web Services 2.0 @Path("/async/longRunning") public class MyResource { @GET public void longRunningOp(@Suspended AsyncResponse ar) { ar.setTimeoutHandler(new MyTimoutHandler()); ar.setTimeout(15, SECONDS); Executors.newSingleThreadExecutor().submit(new Runnable() {public void run() { … ar.resume(result); }}); } }} Asynchronous 처리 예 - Server
- 18. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.18 JSR 339: Java API for RESTful Web Services 2.0 Filter 와Interceptor 로깅, 보안등 cross-cutting concern 들을 위한 용도로 사용 Filter – ContainerRequestFilter(Server), ClientRequestFilter – 주로 헤더 처리에 사용 Interceptor – WriterInteceptor, ReaderInteceptor – 메시지 바디 처리에 사용
- 19. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.19 JSR 344: JSF 2.2 HTML5 친화적인 변화 기본적으로 HTML5 doctype 으로 렌더링 Pass-through attribute Pass-through element
- 20. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.20 JSR 344: JSF 2.2 HTML5 친화적인 변화 <html xmlns="http://www.w3.org/1999/xhtml" xmlns:h="http://xmlns.jcp.org/jsf/html" xmlns:pt="http://xmlns.jcp.org/jsf/passthrough"> <h:head><title>JSF 2.2</title></h:head> <h:body> <h:form id="form"> <h:inputText id="email" value="#{bean.email}" pt:type="email" pt:placeholder="Enter email"/> </h:form> </h:body> </html>
- 21. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.21 JSR 344: JSF 2.2 HTML5 친화적인 변화 <html xmlns="http://www.w3.org/1999/xhtml" xmlns:jsf="http://xmlns.jcp.org/jsf"> <head jsf:id="head"><title>JSF 2.2</title></head> <body jsf:id="body"> <form jsf:id="form"> <input type="text" jsf:id="name“ placeholder="Enter name" jsf:value="#{bean.name}"/> <button jsf:action="#{bean.save}">Save</button> </form> </body> </html>
- 22. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.22 JSR 236: Concurrency Utilities for Java EE 1.0 Java SE Concurrency API 의 확장 Java EE 어플리케이션 컴포넌트에 비동기 처리 기능 지원 4가지 종류의 managed object – ManagedExecutorService – ManagedScheduledExecutorService – ManagedThreadFactory – ContextService Context Propagation, Task Event Notification
- 23. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.23 JSR 236: Concurrency Utilities for Java EE 1.0 public class TestServlet extends HttpPServlet { @Resource(name=“java:comp/DefaultManagedExecutorService”) ManagedExecutorService executor; Future future = executor.submit(new MyTask()); class MyTask implements Runnable { public void run() { . . . // task logic } } } JNDI 를 이용해서 ManagedExecutorService 에 Task 를 전달
- 24. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.24 JSR 236: Concurrency Utilities for Java EE 1.0 ContextService Container 의 Context(JNDI, Classloading 등) 를 capture 하여, 이후에 동일한 Context 에서 어플리케이션이 실행 될 수 있도록 함. – ManagedExecutorService 가 내부적으로 context 전달을 위해서 ContextService 를 사용할 수 있음 Serializable 함 Customize 가능
- 25. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.25 JSR 236: Concurrency Utilities for Java EE 1.0 ContextService // Within your servlet or EJB method… @Resource ContextService ctxSvc; void businessMethod() { Runnable runnableTask= new Runnable() { void run() {// Interact with a database… use component's security}} // Wrap with the current context Runnable runnableTaskWithCtx= (Runnable) ctxSvc.createContextObject(runnableTask, new Class[]{Runnable.class} // Store the runnablewith context somewhere and run later store.putIt(runnableTaskWithCtx);
- 26. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.26 JSR 236: Concurrency Utilities for Java EE 1.0 ContextService // Retreivethe Runnable with Context Runnable runnableTaskWithContext= store.getIt(); // Runnable will run on this thread, but with the context of the servlet/EJB that created it. runnableTaskWithContext.run();
- 27. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.27 Servlet 3.1 Non-blocking I/O Protocol Upgrade (ex. WebSocket) Security Enhancements – <deny-uncovered-http-methods>: Deny request to HTTP methods not explicitly covered
- 28. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.28 Servlet 3.1 public class TestServlet extends HttpServlet protected void doGet(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { ServletInputStream input = request.getInputStream(); byte[] b = new byte[1024]; int len = -1; while ((len = input.read(b)) != -1) { . . . } } } Non-blocking I/O Traditional
- 29. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.29 Servlet 3.1 AsyncContext context = request.startAsync(); ServletInputStream input = request.getInputStream(); input.setReadListener( new MyReadListener(input, context)); Non-blocking I/O: doGet
- 30. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.30 Servlet 3.1 @Override public void onDataAvailable() { try { StringBuilder sb = new StringBuilder(); int len = -1; byte b[] = new byte[1024]; while (input.isReady() && (len = input.read(b)) != -1) { String data = new String(b, 0, len); System.out.println("--> " + data); } } catch (IOException ex) { . . . } } . . . Non-blocking read
- 31. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.31 Java Message Service 2.0 새로운 JMSContext 인터페이스 AutoCloseable JMSContext, Connection, Session, … RunTimeException 사용 메소드 체이닝 사용 JMSProducer Message 전송 방법 간소화 Get More from Less Java EE 7
- 32. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.32 @Resource(lookup = "myConnectionFactory”) ConnectionFactory connectionFactory; @Resource(lookup = "myQueue”) Queue myQueue; public void sendMessage (String payload) { Connection connection = null; try { connection = connectionFactory.createConnection(); Session session = connection.createSession(false, Session.AUTO_ACKNOWLEDGE); MessageProducer messageProducer = session.createProducer(myQueue); TextMessage textMessage = session.createTextMessage(payload); messageProducer.send(textMessage); } catch (JMSException ex) { //. . . } finally { if (connection != null) { try { connection.close(); } catch (JMSException ex) { //. . . } } } 어플리케이션 서버의 리소스 Boilerplate Code 예외 처리 Java Message Service 2.0 JMS 1.1 의 Message 전송 방법
- 33. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.33 Java Message Service 2.0 @Inject JMSContext context; @Resource(lookup = "java:global/jms/demoQueue”) Queue demoQueue; public void sendMessage(String payload) { context.createProducer().send(demoQueue, payload); } JMS 2.0 의 Message 전송 방법
- 34. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.34 JSR 352: Batch Applications for Java Platform 1.0 인터렉티브 하지 않은 대용량 처리, 및 처리 시간이 긴 작업에 적합 배치 실행 방법: 순차, 병렬, 조건(결정) 기반 프로세싱 방법 – 아이템 기반: Chunked (기본옵션) – 태스크 기반: Batchlet
- 35. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.35 JSR 352: Batch Applications for Java Platform 1.0 개념 Job 메타데이타 저장소 배치프로세스 관리 배치 프로세스 각각이 독립적이면서 순차적인 job 의 실행 Chunk
- 36. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.36 <step id=”sendStatements”> <chunk item-count=“3”> <reader ref=”accountReader”/> <processor ref=”accountProcessor”/> <writer ref=”emailWriter”/> </step> …implements ItemReader { public Object readItem() { // read account using JPA } …implements ItemProcessor { Public Object processItems(Object account) { // read Account, return Statement } …implements ItemWriter { public void writeItems(List accounts) { // use JavaMail to send email } JSR 352: Batch Applications for Java Platform 1.0 Chunked Job Specification
- 37. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.37 Contexts and Dependency Injection 1.1 JavaEE7 에서는 beans.xml 디스크립터 지정이 필요 없이 기본적으로 CDI 가 활성화 됨 Bean 디스커버리 모드 – all: All types – annotated: Scope Type 이 지정된 bean – none: CDI 비활성화 @Vetoed 프로그래밍 적으로 비활성화(ex. Spring @Veto) Inteceptor 와 decorator 에 global 우선 순위 및 순서 정의
- 38. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.38 Bean Validation 1.1 Dependency Injection 과의 더욱 단단해진 연계 메소드 레벨의 validation – Constraints on parameters and return values – Check pre-/post-conditions JAX-RS 와의 통합 Java EE 7
- 39. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.39 Built-in Custom @Future public Date getAppointment() { //. . . } public void placeOrder( @NotNull String productName, @NotNull @Max(“10”) Integer quantity, @Customer String customer) { //. . . } Bean Validation 1.1 Method Parameter and Result Validation
- 40. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.40 Java Persistence API 2.1 스키마 생성 지원 – javax.persistence.schema-generation.* properties SynchronizationType.UNSYNCHRONIZED Criteria 를 이용한 대량의 update/delete FUNCTION 을 이용하여 유저가 만든 function 호출 가능 Stored Procedure 실행 가능
- 41. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.41 Java Transaction API 1.2 @Transactional: Define transaction boundaries on CDI managed beans @TransactionScoped: CDI scope for bean instances scoped to the active JTA transaction @Transactional(rollbackOn={SQLException.class}, dontRollbackOn={SQLWarning.class}) public class shoppingCart() {} Java EE 7
- 42. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.42 EJB 3.2 Servlet 3.1 CDI Extensions BeanValidation1.1 Batch 1.0 Web Fragments Java EE 7 JSRs JCA 1.7JMS 2.0JPA 2.1 Managed Beans 1.0 Concurrency 1.0 Common Annotations 1.1 Interceptors 1.2, JTA 1.2 CDI 1.1 JSF 2.2, JSP 2.3, EL 3.0 JAX-RS 2.0, JAX-WS 2.2 JSON 1.0 WebSocket 1.0
- 43. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.43 DOWNLOAD Java EE 7 SDK oracle.com/javaee GlassFish 4.0 Full Platform or Web Profile glassfish.org
- 44. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.44 4.0 Java EE 7 Implementation download.java.net/glassfish/4.0/promoted/
- 45. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.45 Java EE 8 and Beyond Java EE 7 State Management PaaS NoSQL JSON-B Modularity HTML5++ Caching Cloud
- 46. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.46 Adopt-a-JSR Participating JUGs
- 47. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.47 Call to Action Specs: javaee-spec.java.net Implementation: glassfish.org Blog: blogs.oracle.com/theaquarium Twitter: @glassfish NetBeans: wiki.netbeans.org/JavaEE7
- 48. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.48
- 49. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.49 The preceding material 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.
- 50. Copyright © 2012,Oracle and/or its affiliates. All rights reserved.50
Editor's Notes
- #11 JSON is a key technology for data transfer within HTML5 applications, and certainly a lingua franca of the web. With JSON 1.0, Java EE 7 adds new APIs to enable the parsing and generation of JSON text and objects. There are 2 forms that these APIs take: A streaming API -- which is a low level, highly efficient event-driven API for the parsing and generation of JSON text, similar to StAX in the XML world. Streaming API generates events such as START_OBJECT, START_ARRAY, KEY_NAME, and VALUE_STRING. And, more conveniently, an easy-to-use, higher-level object-level API for mapping JSON text into JSON objects and arrays similar to the DOM API in the XML world. Object Model API reads the entire JSON text in the memory and allows to cross-reference objects. If you just want to parse specific parts of JSON text then use Streaming API. In both cases, read JSON data structure from a Reader/InputStream. Write to a Writer/OutputStream.
- #12 The slide show a simple JSON fragment. JSON is a collection of name/value pairs and an ordered list of values. This JSON fragment has several name/value pairs. The first such name/value pair has name “firstName” and value of “John”. Similarly two more name/value pairs. Then there is an array element with name “phoneNumber” and an ordered list of values. The lower part of the slide shows a code fragment on how to create a JsonParser. It can read data from a Stream or a Reader. Iterating through the parser using next() allows to see the different events being emitted. The call to first next places the parser right after the opening {. Call to another next places the parser after “firstName”, and finally the third call to next() places it right after “John”. Calling getString() returns the current value.
- #13 The slide show a simple JSON fragment. JSON is a collection of name/value pairs and an ordered list of values. This JSON fragment has several name/value pairs. The first such name/value pair has name “firstName” and value of “John”. Similarly two more name/value pairs. Then there is an array element with name “phoneNumber” and an ordered list of values. The lower part of the slide shows a code fragment on how to create a JsonParser. It can read data from a Stream or a Reader. Iterating through the parser using next() allows to see the different events being emitted. The call to first next places the parser right after the opening {. Call to another next places the parser after “firstName”, and finally the third call to next() places it right after “John”. Calling getString() returns the current value.
- #14 The slide show a simple JSON fragment. JSON is a collection of name/value pairs and an ordered list of values. This JSON fragment has several name/value pairs. The first such name/value pair has name “firstName” and value of “John”. Similarly two more name/value pairs. Then there is an array element with name “phoneNumber” and an ordered list of values. The lower part of the slide shows a code fragment on how to create a JsonParser. It can read data from a Stream or a Reader. Iterating through the parser using next() allows to see the different events being emitted. The call to first next places the parser right after the opening {. Call to another next places the parser after “firstName”, and finally the third call to next() places it right after “John”. Calling getString() returns the current value.
- #15 JAX-RS 1.1 was a server-side API and introduced standard annotations to publish a REST endpoint. JAX-RS 2.0 now adds a client-side API to access a REST endpoint in a standard way. It provides a higher-level API than HttpURLConnection as well as integration with JAX-RS providers.
- #16 An instance of Client is required to access a Web resource using the Client API. The default instance of Client can be obtained by calling newClient on ClientBuilder. A Web resource can be accessed using a fluent API in which method invocations are chained to build and ultimately submit an HTTP request. Conceptually, the steps required to submit a request are the following: (i) obtain an instance of Client (ii) create a WebTarget (iii) create a request from the WebTarget and (iv) submit a request or get a prepared Invocation for later submission. The benefits of using a WebTarget become apparent when building complex URIs, for example by ex- tending base URIs with additional path segments or templates. Note the use of the URI template parameter {orderId}. The exact value of this template parameter is resolved using resolveTemplate() method. The response to a request typed in the invocation of get() method. In this case, a String representation is returned back. This can also be a POJO where on-the-wire format is converted to POJO using JAX-RS entity providers.
- #17 An instance of Client is required to access a Web resource using the Client API. The default instance of Client can be obtained by calling newClient on ClientBuilder. A Web resource can be accessed using a fluent API in which method invocations are chained to build and ultimately submit an HTTP request. Conceptually, the steps required to submit a request are the following: (i) obtain an instance of Client (ii) create a WebTarget (iii) create a request from the WebTarget and (iv) submit a request or get a prepared Invocation for later submission. The benefits of using a WebTarget become apparent when building complex URIs, for example by ex- tending base URIs with additional path segments or templates. Note the use of the URI template parameter {orderId}. The exact value of this template parameter is resolved using resolveTemplate() method. The response to a request typed in the invocation of get() method. In this case, a String representation is returned back. This can also be a POJO where on-the-wire format is converted to POJO using JAX-RS entity providers.
- #18 An instance of Client is required to access a Web resource using the Client API. The default instance of Client can be obtained by calling newClient on ClientBuilder. A Web resource can be accessed using a fluent API in which method invocations are chained to build and ultimately submit an HTTP request. Conceptually, the steps required to submit a request are the following: (i) obtain an instance of Client (ii) create a WebTarget (iii) create a request from the WebTarget and (iv) submit a request or get a prepared Invocation for later submission. The benefits of using a WebTarget become apparent when building complex URIs, for example by ex- tending base URIs with additional path segments or templates. Note the use of the URI template parameter {orderId}. The exact value of this template parameter is resolved using resolveTemplate() method. The response to a request typed in the invocation of get() method. In this case, a String representation is returned back. This can also be a POJO where on-the-wire format is converted to POJO using JAX-RS entity providers.
- #19 An instance of Client is required to access a Web resource using the Client API. The default instance of Client can be obtained by calling newClient on ClientBuilder. A Web resource can be accessed using a fluent API in which method invocations are chained to build and ultimately submit an HTTP request. Conceptually, the steps required to submit a request are the following: (i) obtain an instance of Client (ii) create a WebTarget (iii) create a request from the WebTarget and (iv) submit a request or get a prepared Invocation for later submission. The benefits of using a WebTarget become apparent when building complex URIs, for example by ex- tending base URIs with additional path segments or templates. Note the use of the URI template parameter {orderId}. The exact value of this template parameter is resolved using resolveTemplate() method. The response to a request typed in the invocation of get() method. In this case, a String representation is returned back. This can also be a POJO where on-the-wire format is converted to POJO using JAX-RS entity providers.
- #20 An instance of Client is required to access a Web resource using the Client API. The default instance of Client can be obtained by calling newClient on ClientBuilder. A Web resource can be accessed using a fluent API in which method invocations are chained to build and ultimately submit an HTTP request. Conceptually, the steps required to submit a request are the following: (i) obtain an instance of Client (ii) create a WebTarget (iii) create a request from the WebTarget and (iv) submit a request or get a prepared Invocation for later submission. The benefits of using a WebTarget become apparent when building complex URIs, for example by ex- tending base URIs with additional path segments or templates. Note the use of the URI template parameter {orderId}. The exact value of this template parameter is resolved using resolveTemplate() method. The response to a request typed in the invocation of get() method. In this case, a String representation is returned back. This can also be a POJO where on-the-wire format is converted to POJO using JAX-RS entity providers.
- #36 A Job is an entity that encapsulates an entire batch process. A Job will be wired together via a Job Specification Language. A Job has one to many steps, which has no more than one ItemReader, ItemProcessor, and ItemWriter. A job needs to be launched (JobOperator), and meta data about the currently running process needs to be stored (JobRepository). A Step is a domain object that encapsulates an independent, sequential phase of a batch job. JobOperator provides an interface to manage all aspects of job processing, including operational commands, such as start, restart, and stop, as well as job repository related commands, such as retrieval of job and step executions. A job repository holds information about jobs currently running and jobs that have run in the past. The JobOperator interface provides access to this repository. The repository contains job instances, job executions, and step executions. ItemReader is an abstraction that represents the retrieval of input for a Step, one item at a time. ItemWriter is an abstraction that represents the output of a Step, one batch or chunk of items at a time. ItemProcessor is an abstraction that represents the business processing of an item. While the ItemReader reads one item, and the ItemWriter writes them, the ItemProcessor provides access to transform or apply other business processing.
- #37 A Job is defined using Job Specification Language. For Java EE 7, this is defined using an XML document, called as Job XML. Job XML typically consists of many steps, this contains one simple step. The step is either a chunk or batchlet – this one is chunk. This one is a chunk and has a reader, processor, and writer. The ref attribute refers to CDI resolvable bean name bundled with the archive. The item-count attribute defines the chunk size, i.e. the number of items processed at one time. The reader, processor, and writer work together for a chunk number of items at a time. All of this is done within a transaction, with automatic checkpointing. Now lets take a look how reader, processor, and writer are implemented. This Job XML defines a simple use case of sending regular email statements. Reader implements ItemReader interface. The main method to override there is readItem which reads the item – this could be from any stream or database or JMS queue. For example, you may read Account information using JPA. Processor implements ItemProcessor interface. processItem takes the item just read, applies business processing and returns a new object (possibly different type). This new object is now aggregated with the writer. For example, you may read an Account object and return a Statement object. Writer implements ItemWriter interface. writeItems has a List parameter where all the aggregated items are available and writes it out. In our case, you will use JavaMail to send an email to List<Statement>.
- #38 CDI is making the platform lot more cohesive and is becoming a core component model. Also, CDI is now enabled by default in Java EE 7, without the requirement to specify a beans.xml descriptor. If beans.xml exists with version 1.1, then a new attribute bean-discovery-mode can be specified on the top level <beans>. “all” value can be specified to enable injection all beans in the archive. “annotated” value is used to inject beans with a bean defining annotation – such as one with a CDI scope. And “none” can be used to completely disable CDI. A new annotation @Vetoed is added to enable programmatic disablement of classes. This functionality was available in other frameworks and now in the standards.
- #39 The first version introduced Bean Validation integration with just JPA and JSF. Now Bean Validation 1.1 is more tightly aligned with the platform. For example, now validation constraints can be specified on POJO – either to validate the method parameters or return type. If the constraints specified on method parameters are not met, i.e. the pre-conditions are not met, then a ConstraintViolationException is thrown. Similarly if the constraint specified on the return type is not met then a ConstraintViolationException is thrown instead of returning the result. This ensures that post-conditions of invoking the method are met correctly. BV 1.1 also introduces an integration with JAX-RS. So you can specify these constraints on your JAX-RS endpoints and the constraints are automatically verified.
- #40 This code shows two simple methods, one with a few parameters and void return type. Another method with no parameters and a Date return type. In the first method, @NotNull is specified on the first two constraint ensuring that none of these parameters are null. The second parameter also has @Max indicating that this parameter cannot be more than 10. These are built-in constraints. A custom constraint, such as @Customer, the one specified on the third parameter, can be specified. This custom constraint will define application-specific constraint logic. There is no need to call if/else within a method. This validation will be automatically triggered using standard CDI Interceptor Bindings and trigger ConstraintViolationException is the constraints are not met. Similarly, for getAppointment() method, if the return value is not in future, per the current JVM timestamp, then a ConstraintViolationException is thrown as well. In first case, if pre conditions is not met otherwise then the method is not invoked. In the second case, post conditions must be met for a clean invocation of the method.
- #41 JPA allows to generate an Entity from a database table. JPA 2.1 adds new javax.persistence.schema-generation.* properties that allow to generate database schema or scripts from Entity classes. There is also a provision to load the database, i.e. DML, using these properties. By default, a container-managed persistence context is of SynchronizationType.SYNCHRO- NIZED and is automatically joined to the current transaction. A persistence context of SynchronizationType.UNSYNCHRONIZED will not be enlisted in the current transaction, unless the EntityManager joinTransaction method is invoked. Similarly, by default, an application-managed persistence context that is associated with a JTA entity manager and that is created within the scope of an active transaction is automatically joined to that transaction. An application-managed JTA persistence context that is created outside the scope of a transaction or an application-managed persistence context of type SynchronizationType.UNSYNCHRONIZED will not be joined to that transaction unless the EntityManager joinTransaction method is invoked. JPA 2 added typesafe Criteria API but that allowed only querying the database. JPA 2.1 updates the API to allow update/delete as well. JPA 2.1 also adds the capability to invoke a stored procedure or user defined functions.
- #42 A significant change in JTA allows to convert any POJO into a transactional object. The javax.transaction.Transactional annotation provides the application the ability to declaratively control transaction boundaries on CDI managed beans, as well as classes defined as managed beans by the Java EE specification, at both the class and method level where method level annotations override those at the class level. The javax.transaction.TransactionScoped annotation provides the ability to specify a standard CDI scope to define bean instances whose lifecycle is scoped to the currently active JTA transaction. This annotation has no effect on classes which have non-contextual references such those defined as managed beans by the Java EE specification .
- #43 Different components can be logically divided in three different tiers: backend end, middle tier, and web tier. This is only a logical representation and the components can be restricted in a different tier based upon application’s requirement. JPA and JMS provide the basic services such as database access and messaging. JCA allows connection to legacy systems. Batch is used for performing non-interactive bulk-oriented tasks. Managed Beans and EJB provide a simplified programming model using POJOs to use the basic services. CDI, Interceptors, and Common Annotations provide concepts that are applicable to a wide variety of components, such as type-safe dependency injection, addressing cross-cutting concerns using interceptors, and a common set of annotations. Con‐ currency Utilities can be used to run tasks in a managed thread. JTA enables Trans‐ actional Interceptors that can be applied to any POJO. CDI Extensions allow you to extend the platform beyond its existing capabilities in a standard way. Web services using JAX-RS and JAX-WS, JSF, JSP, and EL define the programming model for web applications. Web Fragments allow automatic registration of third- party web frameworks in a very natural way. JSON provides a way to parse and generate JSON structures in the web tier. WebSocket allows to setup a bi-directional full-duplex communication channel over a single TCP connection. Bean Validation provides a standard means to declare constraints and validate them across different technologies.
- #44 Java EE 7 SDK can be downloaded from oracle.com/javaee. Wait a moment, repeat the URL and encourage attendees to bookmark the URL and spread the word. GlassFish Server Open Source Edition 4.0 Web Profile and Full Platform can be downloaded from glassfish.org.
- #46 This diagram shows some of the target items for Java EE 8. This is only a thought process at this time and everything is completely subject to discussion with the Java EE Expert Group. Nothing is committed at this time. JSON-B will provide a support for binding POJOs to JSON structure. JSR 107 will provide support for caching. Support for modular Java EE applications will be built upon Java SE modularity. Standards-based PaaS/Cloud will definitely be looked upon. Thin Server Architecture or HTML5++ will be looked upon. State Management, NoSQL, and several other options.
- #47 Adopt-a-JSR is an initiative started by JUG leaders to encourage JUG members to get involved in a JSR, in order to increase grass roots participation. This allows JUG members to provide early feedback to specifications before they are finalized in the JCP. The standards in turn become more complete and developer-friendly after getting feedback from a wide variety of audience. The JUGs organized hackathons, created sample applications, presented on different Java EE 7 topics at conferences, filed bugs on implementation. Overall they led to a much better Java EE 7. This release was not possible without support of different JUGs. They kept us honest. Here are some specific examples on how different JUGs were involved: London Java Community (LJC) organized a WebSocket and JSON Hack Day. The event was sold out within 2 hours and had 17 people on the waiting list. The event started with a presentation on explaining the APIs in Java API for WebSocket (JSR 353) and Java API for JSON Processing (JSR 353). The attendees designed a Market Ticker application. All the presentation material and source code was shared publicly. LJC also created projects (cdiex-palindrom-jsf and cdiex-datastore) to test CDI 1.1 specification. Chennai JUG is building a multi-player game that can be played across the Internet. The application uses Java API for WebSocket 1.0 (JSR 356), Java API for JSON Processing 1.0 (JSR 353), Java Persistence API 2.1 (JSR 338), JavaServer Faces 2.2 (JSR 344) and Batch Applications for Java Platform (JSR 352) and/or Enterprise JavaBeans 3.2 (JSR 345) and so provide a holistic experience of building a Java EE 7 application. The energetic JUG meets regularly using G+ hangouts and in the neighborhood coffee shops to coordinate. And then they go hacking the application on github. There are 5 developers that are regularly contributing to the application and the JUG plans to incorporate several other technologies as part of an ongoing effort. Morocco JUG will be presenting on Java EE 7, WebSocket, and JSON at Java Developer Conference, Cairo, Egypt. Cologne JUG had a meetup on about JSF 2.2 and another one on CDI 1.1 (video). BeJUG has adopted JSR 356 have planned a hackathon on Mar 6th. They plan to build a cross-browser Tic-Tac-Toe application using JSR 356. One of the JUG members is on its way to become a committer in Tyrus - the Reference Implementation for JSR 356. Ceara JUG has planned a set of presentations on Mar 9 by on JAX-RS 2.0 (JSR 339), Java API for JSON Processing (JSR 353), JavaServer Faces 2.2 (JSR 344), and Java API for WebSocket (JSR 356). San Francisco JUG organized a Java EE 7 and WebSocket session and planning a session on JAX-RS 2.0. SouJava is contributing by adding new features from JSF 2.2 to Scrum Toys.