Transcript J2EE modules

J2EE Blueprint
Chapter One ：Introduction
Chin-Yi Tsai
Outline

Introduction

Web Services

Challenges of Web Services Development
• Security, Reliability, Availability, Scalability

Typical Web Services Scenarios

J2EE：The Platform for Web Services
2
Introduction

J2EE platform has become an integrated standard for
implementing and deploying portable and distributed
enterprise application.

J2EE platform has added support for web servicespecific components and technologies.
• Web service: interoperability
• Add portability to web services

J2EE 1.4 platform is the platform of choice for
developing and deploying portable and interoperable
Web Services (new) and enterprise applications (old).
3
This Book …

About developing robust, effective Web services on
the Java 2 platform, Enterprise Edition (J2EE).

Describe the technologies used for Web Service.

Guidelines for using these technologies to design and
develop web services.
4
Web Service Definition

W3C: A Web service is a software system identified by a URI
whose public interfaces and bindings are defined and described
using XML. Its definition can be discovered by other software
systems. These systems may then interact with the Web service
in a manner prescribed by its definition, using XML-based
messages conveyed by Internet protocols.

A Web service is a software application/component, accessible
on the Web through an URL, that is accessed by clients using
XML-based protocols, such as Simple Object Access Protocol
(SOAP) sent over accepted Internet protocols, such as HTTP.
Clients access a Web service application through its interfaces
and bindings, which are defined using XML artifacts, such as a
Web Service Definition Language (WSDL) file.
5
Web Service

Enable application-to-application communication and
interoperability.

These reusable, self-contained application provide a
standardized way for applications to expose their
functionality over the Web or communicate with
other applications over a network, regardless of the
application’s implementation, programming language,
or computer platform.

Web services promote interoperability across
different platforms, systems, and language.
6
Web Service

A web service is a service-oriented architecture,
which is simply a collection of services that
communicate with each other through well-defined
and well-known interface.
7
Service-Oriented Architecture
UDDi
XML
UDDI
WSDL
SOAP
Service
provider
Service
requestor
Well-defined interface
Registry
Query
Access the service directly
8
Web Service Related Standard

UDDI
• 服務註冊
• 服務查詢

WSDL
• 服務描述
• 介面

SOAP
•如何包裝 & 傳送

XML
9
Benefits of Web Services

Interoperability in heterogeneous environment
• Key benefit

Business services through the web

Integration with existing systems
•
•
•
•

已有大量的資料存在舊有的EIS
replace or …
Standard way to access middle-tier and back-end services
Database management system and transaction monitors
Freedom of choice
• Tools, products, and technologies

Support more client types

Programming productivity
• common programming standard
10
Challenges of Web Service Development

Evolving technologies and products
• Standard and specification
• Interoperability
• Coordination


workflow
Security
• Authentication
• Authorization
• Security at the transport and message level
11
Challenges of Web Service Development

Reliability, availability, and scalability
• Large-scale distributed applications





dose a client have to wait for the web service?
the number of failures that occur in a given time
period
Handler multiple client interactions (increasing)
Efficiently manage system resources and services
Automatic load balancing and failover
12
Typical Web Service Scenarios

Interaction between business partners, supply chain
management, inventory management, and even
simple services.

Issues
• Interoperability requirement
• Integration requirement (EIS)
• Types of client
13
Adventure Builder enterprise –existing enterprise

Web service to integrate with its numerous partners
14




Integrating with business partners
Integrating with existing enterprise information
system
Reaching diverse clients
Aggregation of partner data
15
Demo

http://140.134.26.27:8080

http://140.134.26.27:4848
• Application Server Admin Console

http://140.134.26.27:8080/ab/main.screen
• JAVA ADVENTURE BUILDER DEMO
16
Types of J2EE JAR Files





Web Application Archive (WAR)
EJB JAR
J2EE Application Client JAR
Resource Adapter Archive (RAR)
Enterprise Application Archive (EAR)
17
J2EE application modules components

J2EE application consists of one or more J2EE modules and
one J2EE deployment descriptor, packaged in an Enterprise
Archive (EAR) file, which is a JAR file with the .EAR
extension.

J2EE modules : J2EE modules consist of one or more J2EE
components of the same type and one component deployment
descriptor.
• Web module
• EJB module
• Application client module
18
J2EE 1.4：The Platform for Web Services

The J2EE platform is designed to provide server-side
and client-side for developing Web Services and
distributed, multi-tier enterprise application.

Multi-tier model

Component-based development
• reusability

Container-based component management
19
Portability

Define a set of related specification
•
•
•
•



The Enterprise JavaBean
The Java Servlet spec
JSP spec
Java API for XML-based RPC spec
J2EE Compatibility Test Suite
J2EE reference implementation
J2EE SDK
20
Support for the WS-I standard for interoperability

The J2EE 1.4 platform includes spec and tech that
support SOAP, WSDL, UDDI, and ebXML.
• Simple Object Access Protocol
• Web Service Description Language
• Electronic Business using eXtensible Markup Language






Java API for XML-based RPC (JAX-RPC)
Java API for XML Messaging (JAXM)
SOAP with Attachments API for Java (SAAJ)
Java API for XML Registries (JAXR)
Java API for XML Processing (JAXP)
Java API for XML Binding (JAXB)
21
J2EE Platform Benefits

Simplifies architecture and development

Ensures support for emerging Web service standard

Ensure the development of portable and interoperable services

Allow for integration with existing information system
•
•
•
•

Industry-standard API
J2EE Connector architecture
JDBC
JMS
Is scalable to meet demand variations
• J2EE containers provide transaction support, database connections, life cycle
management, and other services that are both scalable and require no code from
application developers

Provides a flexible security model
• EJB, Servlet API
• Specified at deployment time
22
J2EE Platform









Java Mail API
Java Message Service
Java Naming and Directory Interface (JNDI) API
Java Transaction API
JDBC API
EJB
RMI-IIOP
JSP
Servlet
23
24
J2EE Technologies

Components

Services

Communications
25
Three Kinds of Components

Client component
• Applets
• Standalone java application client

Web component
• Servlet
• JSP

Enterprise JavaBeans是一種以分散式運算為基礎的元
件架構
•部署時做最佳化
•允許被部署在相容的 J2EE 伺服器上
26

Session Beans 主要處理企業邏輯
• 通常面對的是 Client (EJB Client)
• 分為兩大類



Stateful Session Bean
Stateless Session Bean
Entity Beans 主要負責處理資料庫處理
• 通常 Entity Bean 代表資料庫的表格
• 分為兩大類



Bean Managed Persistence
Container Managed Persistence
Message Driven Beans 主要負責處理 MQ Server 所收到的
訊息
• 通常 Message Driven Beans 不會主動被觸發
• 可以處理兩大種類的訊息


Topic
Queue
27
Services

Container
• Application client container
• Web container
• EJB container

Container services
•
•
•
•
Naming service
Deployment service
Transaction service
Security service
28
Communication


These communication tech bring the platform’s component
and services together, making the J2EE platform an integrated,
standard platform for developing portable, interoperable
enterprise application and web service.
Internet protocol
• HTTP, TCP/IP, SSL

Remote Method Invocation protocol
• JRMP

Messaging technologies
• JMS and JavaMail API

Web Service technologies
• SOAP: Java API for XML-based RPC
• UDDI: Java API for XML Registries
29
Book Organization

Chapter 2
• Standard and technologies

Chapter 3
• Service endpoint design

Chapter 4
• Client design

Chapter 5
• XML processing

Chapter 6
• Application and data integration

Chapter 7
• Security

Chapter 8
• Application architecture
30