J2EE(Java EE) Overview

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Objectives

• Introdutions to Java EE enterprise application development

  • review development basics

  • Java ee architecture and apis

  • Important terms and concepts

  • Java ee application, programming, assembly, development

Structure

• Java EE architecture and APIs

  • Servlet

  • JSP

  • JDBC/JTA

  • MVC

  • Web应用实例

  • 中间件 RPC RMI

  • JMS

  • JNDI

  • EJB

  • Java EE

  • Security

  • Java Mail

• Java EE enterprise appliaction development

  • Structs, Spring, Hibernate

reference

The Java EE Tutorial，Release 8 September 2017

java offical doc

Development History

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Enterprise applications

• distributed

• transcational

• portable

• speed

• security

• reliability

• business logic

Overview

• a powerful set of APIs

• a simplified programming model

  • More annotations less XML

  • Dependency injection : hiding the creation and lookup of resources from application

Java EE Application Model

• Begins with java language and java virtual machine

• proven protability, security, developed productivity

• defines an architecture

• the needed work to implement services

  • business logic and presentation logic

  • Standard system services

• a distributed multitiered application model

• application components

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Security

• enables security constraints to be defined at deployment time

• procides standard declarative access control rules

• standard login mechanisms

• works in varieties of security environments without changing the source code

Java EE Components

• a self-contained functional software unit

• Applications clients and applets

• web components

• EJB components

Java EE Clients

• Appliations clients and applets

• web client

Web Client

• Dynamic web pages

• web browser

• thin client

• enterprise beans

Application Clent

• Richer user interface

• gui

• Directly access enterprise

JavaBeans

• Server and client tiers

• manage data flow

Web Components

• Servlets or web pages using JavaServer Faces or JSP

• Might include a javaBeans component

Business Components

• Enterprise JavaBeans

• Logic

Enterprise Information System Tier

• Enterprise infrastructure systems

Java EE Containers

• handle transaction and state management, multithreading, resource pooling

• provides underlying services

Container Service

• interface between compents and low-level functionality

• Assembled into a Java EE module and deployed into its container

• specifying container settings

• e.g.

  • security

  • transaction

  • JNDI lookup

  • remote connectivity

Container Types

• Java EE server

  • Enterprise JavaBeans container

  • Web container

• Application client container

• Applet container

relationships

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web services support

• xml,APIs,tools

• Extensible markup language

• Simple object access protocol

• Web services description languages

Assembly and Deployment

• Packaged into units

  • components

  • Deployment descriptor

Packaging

packaging Applications

• Java Archive jar

• Web Archive war

• Enterprise Archive EAR

deployment descriptors

• Java ee deployment descriptor

• Runtime deployment descriptor

Java EE module

• EJB modules jar

• web modules war

• application client modules jar

• Resource adapter modules rar

Development Roles

• Java EE product provider

  • Java EE specification

  • Application server vendors

• Tool provider

  • Development, assembly, packaging tools

• Application Component Provider

  • Web components

  • Enterprise beans

  • applets

  • Application client

• application Assembler

  • ear file

• application Developer and administrator

  • configures and deploys java ee application

Java EE 8 APIs

Enterprise JavaBeans Technology

• session bean

• Message-driven bean

• Enterprise javabean

• spring

Java Servlet Technology

• Define http-specific servlet classes

• a request-response programing model

JavaServer Faces

• user interface framework

JavaServer Pages Technology

• Text-based document

• Static data

• Jsp elements

java persistence api(jpa)

• Object-relational mapping

• Java se

• hibernate

java transaction api(eta)

• Default auto commit

• two separate database access operations

jax-rs

• Java api for restful web service

  • development of web services

  • Reprentational State Transfer (REST)

Managed Beans

• resource injection, lifecycle callbacks, interceptors

contexts and dependency injection for the java ee platform (CDI)

• Make it easy to use enterprise beans

• Integrate different kinds of components

• a standard set of annotations

Bean Validation

• Define validation constraints in one place

• share them across the different layers

Java Message Service API

• Create,send,receive,read message

• Distributed communication

Java EE Connector Architecture

• Tool vendors

• System integrators

• access to enterprise information systems

JavaMail API

• send mail

JACC and JASPIC

• Java Authorization Contract for containers

• Java Authentication Service Provider Interface

Java EE Security API

• simplify the security apis

json processing

JSON is a text-based data exchange format

Praise, transform query json data

json binding

converting java objects to and from json messages

concurrency utilities

• providing asynchronous capability

Batch Applications for the java Platform

• Batch jobs are tasks that can be executed without user interaction

• batch framework :creating and running batch jobs in Java applications

Java Database Connectivity API

• Invoke SQL commands

  • enterprise bean

  • servlet or a jsp

• Application-level interface, service provider interface

java naming and directory interface( JNDI)

• access multiple naming and directory services

• Method for peforming standard directory operations

• store and retrive any type of named java object

Java Authentication and Authorization Service (JAAS)

• Authenticate and authorize a specific user or group of users

common annotations

• Declarative style of programming

Web服务器和应用服务器

• web ： tomcat,jetty

• Ebb container, jboss,wildfly

• Application server, IBM websphere, oracle weblogic