Contents
Preface
1 Introduction
Course Objectives 1-2
Course Environment 1-4
Course Overview 1-5
About the Course Applications 1-8
Order Entry Schema 1-9
Human Resources (HR) Schema 1-10
HR Application Flow Diagram 1-11
Summary 1-12
2 J2EE OverviewObjectives
Objectives 2-2
Java 2, Enterprise Edition Platform 2-3
J2EE Platform 2-4
Benefits of the J2EE Platform 2-5
J2EE Components 2-7
J2EE 1.3 Components 2-8
J2EE Architecture 2-9
Client-Tier Components 2-10
J2EE Web-Tier Components 2-11
What Is a Servlet? 2-13
What Is a JavaServer Page (JSP)? 2-14
Web-Tier Components: Summary 2-15
Business-Tier Components 2-16
Enterprise JavaBeans (EJB) 2-17
J2EE Communication APIs 2-18
J2EE Server 2-19
Oracle Application Server 10g Containers for J2EE (OC4J) 2-21
J2EE Applications 2-22
Packaging J2EE Application Components 2-23
JARs 2-24
WARs 2-25
EJB JARs 2-26
EARs 2-27
EAR File Structure for a J2EE Application: Example 2-28
OC4J Architecture 2-29
OC4J Server Configuration Files 2-30
Relation of Configuration Files 2-31
Data Sources 2-32
Application Logging 2-33
J2EE Application Deployment to
Oracle Application Server 10g 2-34
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Oracle Enterprise Manager 2-35
JDeveloper and J2EE 2-36
Oracle JDeveloper 10g Environment 2-37
Oracle JDeveloper 10g Visual Design Tools 2-38
Summary 2-39
Practice 2-1: Overview 2-40
3 Designing J2EE Applications
Objectives 3-2
Realizing J2EE Benefits 3-3
J2EE Issues 3-4
J2EE Design Patterns 3-5
Implementing Design Patterns by Using MVC 3-6
The Model 3-7
The View 3-8
The Controller 3-9
MVC in Oracle Application Server 10g Containers for J2EE 3-10
Designing J2EE Applications 3-11
Flow Diagram: Example 3-12
Summary 3-13
Practice 3-1: Overview 3-14
4 Creating the Web Tier: Servlets
Objectives 4-2
Overview 4-3
About Java Servlets 4-4
Principal Features of Servlets 4-5
Life Cycle of Servlets 4-6
HTTP Servlets 4-7
Inside an HTTP Servlet 4-8
Servlet: Example 4-9
The doGet() Method 4-10
The doPost() Method 4-11
The HttpServletRequest Object 4-12
The HttpServletResponse Object 4-13
Methods for Invoking Servlets 4-14
Your First Servlet 4-15
Handling Input: The Form 4-16
Handling Input: The Servlet 4-17
Initialization and Destruction 4-18
Error Handling 4-19
Debugging a Servlet 4-20
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SingleThreadModel 4-21
JDeveloper Environment 4-23
Servlet Mapping 4-24
Servlet Mapping in JDeveloper 4-25
Invoking a Servlet 4-26
Specifying J2EE Web Module Settings 4-27
Creating a Connection to Oracle Application Server 10g 4-28
Deploying to OC4J 4-29
Summary 4-30
Practices 4-1, 4-2, and 4-3: Overview 4-31
5 Accessing the Database with Servlets
Objectives 5-2
Review of JDBC 5-3
Querying in JDBC 5-4
JDBC and Servlets 5-5
Synchronizing Shared Resources 5-6
Transaction Handling 5-7
Connection Pooling 5-9
Data Sources 5-10
Data Source Definition 5-11
data-sources.xml: Example 5-12
Using Data Sources 5-13
Summary 5-14
Practice 5-1: Overview 5-15
6 Using Advanced Techniques in Servlets
Objectives 6-2
Overview 6-3
HTTP Headers 6-4
Request Headers 6-5
Sending a Response 6-6
Response Headers 6-7
Setting Status Codes 6-8
Example 6-9
Sending Multimedia Content 6-10
Cookies 6-12
Setting Cookies 6-13
Retrieving Cookies 6-14
About State Preservation 6-15
State Preservation: Example 6-16
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ServletContext 6-17
RequestDispatcher 6-18
RequestDispatcher: Example 6-19
Servlet Filters 6-20
Using Filters 6-21
doFilter() Method 6-22
Using Filters 6-23
Configuring Filters 6-24
Application Lifecycle Events 6-25
ServletContext Events 6-26
HttpSession Events 6-27
Example of an Event Listener 6-28
Error Handling 6-29
Summary 6-30
Practices 6-1 and 6-2: Overview 6-31
7 Maintaining State in J2EE Applications
Objectives 7-2
Overview 7-3
Session Basics 7-4
Threading 7-6
URL Rewriting 7-7
HttpSession 7-8
Session Objects 7-9
Session-Based Page Counter 7-10
Session Life Cycle 7-11
Session Tracking in OC4J 7-12
Sessions and Events 7-13
Creating Distributable Applications 7-17
Summary 7-18
Practice 7-1: Overview 7-19
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8 Creating the Web Tier: JavaServer Page
Objectives 8-2
JavaServer Pages 8-3
Comparing Servlets and JSPs 8-4
Invoking JSPs 8-5
The Date JSP 8-6
The Date Servlet 8-7
Automated JSP Features 8-8
JSP Life Cycle 8-9
Basic JSP Elements 8-10
Declarations 8-11
Expressions 8-12
Scriptlets 8-13
Implicit Objects 8-14
Example 8-16
Directives 8-18
include: Example 8-19
page Directive 8-20
JSP and JavaBeans 8-22
Using JavaBeans with JSP 8-23
scope Attribute of <jsp:useBean> Tag 8-25
Accessing and Setting Bean Property 8-26
JSP XML Document 8-28
Traditional Syntax Versus XML Syntax 8-29
JDeveloper and JSPs 8-31
Creating JSPs Visually 8-32
JSP Tag Insight 8-33
Summary 8-34
Practices 8-1, 8-2, and 8-3: Overview 8-35
9 Modularizing JavaServer Pages Development with Tags
Objectives 9-2
Custom Tags 9-3
Custom Tag Library Components 9-4
Tag Handler: Example 9-5
Tag Library Descriptors 9-6
Using a Custom Tag 9-7
Tags with Attributes 9-8
Creating a Custom Tag in JDeveloper 9-9
Tag Libraries in JDeveloper 9-10
Registering Tag Libraries 9-11
Using Tag Insight 9-14
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JSP Standard Tag Library (JSTL) 9-15
Core Tag Library 9-16
Utilizing Core Tags 9-18
Expression Language 9-19
Using Iteration Tags 9-20
Using the URL Tags 9-21
XML Tag Library 9-23
SQL Tag Library 9-24
Accessing a Database with SQL Tags 9-25
Querying Using SQL Tags 9-26
Inserting, Updating, and Deleting Data 9-27
Formatting Tags 9-28
Internationalization Concepts 9-29
Internationalizing Strings 9-30
Formatting Numbers and Dates 9-31
Transforming XML Documents 9-34
JSTL in JDeveloper 9-35
Summary 9-36
Practice 9-1: Overview 9-37
10 Communicating in J2EE
Objectives 10-2
Overview of RMI 10-3
Role of RMI in J2EE 10-4
Communication in a J2EE Environment 10-5
How Clients Locate a Distributed Component 10-7
Java Naming and Directory Interface (JNDI) 10-8
J2EE Container and JNDI Interface 10-9
Naming Service 10-10
JNDI Terminology 10-11
Main JNDI Class and Interface 10-12
Accessing an Object in JNDI Namespace 10-13
Getting the JNDI InitialContext 10-14
Initial Context Factories 10-16
lookup() Method 10-17
Obtaining a Reference to a Local Resource 10-18
Obtaining a Reference to a Remote Resource 10-19
Setting JNDI Environment Properties 10-20
Using RMI over HTTP Tunneling 10-24
Using Environment References with JNDI 10-25
Configuring Environment Variables 10-26
Specifying an EJB Reference 10-28
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Configuring EJB References 10-29
Configuring Data Source References 10-31
Summary 10-33
Practice 10-1: Overview 10-34
11 Creating the Business Tier: Enterprise JavaBeans
Objectives 11-2
Enterprise JavaBeans (EJB) 11-3
When to Use EJBs 11-4
Types of EJBs 11-5
Session Beans 11-7
Entity Beans 11-9
Message-Driven Beans 11-10
EJB Architecture 11-11
EJB Server 11-12
EJB Container 11-13
Services Provided by the EJB Container 11-14
EJB Client 11-16
EJB Interfaces and Classes 11-17
Remote Interface and Remote Object 11-18
Home Interface and Home Object 11-19
Local Interface and Local Home Interface 11-20
EJB Bean Class 11-21
The EJB Deployment Process 11-22
ejb-jar.xml File 11-23
orion-ejb-jar.xml File 11-24
Creating an EJB in JDeveloper 11-25
Using the EJB Wizard 11-26
Using the EJB Wizard 11-27
Adding Methods to the Bean 11-28
Deploying to Oracle Application Server 10g from JDeveloper 11-29
Summary 11-30
Practice 11-1: Overview 11-31
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12 Implementing Business Tasks with Session EJBs
Objectives 12-2
Session Beans 12-3
javax.ejb.SessionBean Interface 12-5
Types of Session Beans 12-7
When to Use Session Beans 12-9
Life Cycle of a Stateless Session Bean 12-11
Home Interface for Stateless Session Beans 12-12
Remote Interface for Stateless Session Beans 12-14
The Session Bean Class 12-15
The Session Bean Class: Business Methods 12-17
Bean Class for the Stateless Session Bean 12-18
Deployment Descriptor 12-19
Client Application 12-20
Client Application for Stateless Session Beans 12-21
Life Cycle of a Stateful Session Bean 12-25
Home Interface for Stateful Session Bean 12-26
Client Application for Stateful Session Bean 12-27
Summary 12-28
Practices 12-1 and 12-2: Overview 12-29
13 Managing Persistent Data in the Business Tier
Objectives 13-2
Entity Beans 13-3
Representing Data in Entity Beans 13-5
When to Use Entity Beans 13-6
Callback Methods to Load and Store Data 13-7
Session Beans Versus Entity Beans 13-9
Types of Entity Beans 13-11
BMP Beans Versus CMP Beans 13-12
Components of an Entity Bean 13-14
Creating, Removing, Finding, and Selecting Entity Beans 13-15
Home Interface of an Entity Bean 13-17
Creating a Bean Instance 13-18
Finding an Entity Bean Instance 13-20
Removing an Entity Bean 13-22
Home Methods of Entity Beans 13-23
Component Interfaces of an Entity Bean 13-24
Primary Key Class of an Entity Bean 13-25
Bean Class of an Entity Bean 13-26
javax.ejb.EntityBean Interface 13-28
Life Cycle of an Entity Bean 13-30
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Deployment Descriptor 13-32
Summary 13-35
Practice 13-1: Overview 13-36
14 Achieving State Management in the Business Tier
Objectives 14-2
Features of BMP Entity Beans 14-3
Developing a BMP Entity Bean 14-4
Features of CMP Entity Beans 14-5
Implementing Methods in CMP Beans and BMP Beans 14-7
Developing a CMP Entity Bean 14-9
CMP Bean: Example 14-10
Bean Class of a CMP EJB: CMP Fields 14-11
Remote Interface: Departments 14-12
Home Interface: DepartmentsHome 14-13
Bean Class: DepartmentsBean 14-14
Deployment Descriptor ejb-jar.xml 14-17
Mapping CMP Fields to Database Table Columns 14-21
Default Mapping of CMP Fields to Database Table Columns 14-22
Explicit Mapping of CMP Fields to Database Table Columns 14-23
Client for Departments Bean 14-25
Summary 14-28
Practice 14-1: Overview 14-29
15 Container-Managed Relationships (CMRs)
Objectives 15-2
Relationships 15-3
Implementing Relationships 15-4
Cardinality and Direction of Relationships 15-5
One-to-One Relationships 15-7
One-to-Many Relationships 15-8
Many-to-Many Relationships 15-9
Oracle TopLink 15-10
TopLink: Integration of J2EE Applications with Data Sources at Run Time 15-11
TopLink: Integrated with Oracle JDeveloper 10g 15-12
Implementing Relationships 15-13
Defining Abstract Accessor Methods 15-14
Accessor Methods in 1:1 Relationships 15-15
Accessor Methods in 1:M Relationships 15-16
Checking Relationship Mappings in JDeveloper 15-17
Accessor Methods in M:N Relationships 15-18
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Implementing a Relationship in the Deployment Descriptor 15-19
Implementing 1:1 Relationships 15-21
Implementing 1:M Relationships 15-23
Implementing M:N Relationships 15-25
Mapping Relationship Fields to Database 15-27
Default Mapping of Relationship Fields 15-28
Explicit Mapping of Relationship Fields 15-30
Using JDeveloper to Create CMR Beans 15-31
Summary 15-32
Practice 15: Overview
16 Developing Message-Driven Beans
Objectives 16-2
Overview of Messaging Systems 16-3
Types of Message Consumption 16-4
Java Message Service (JMS) 16-6
JMS Application Architecture 16-7
Point-to-Point Model 16-8
Publish-and-Subscribe Model 16-9
Using JMS Interfaces 16-10
JMS Message Structure 16-12
Sending a Message to a Queue 16-13
Receiving Messages 16-15
Asynchronous Message Delivery 16-16
Message-Driven Beans 16-17
MDB Architecture 16-18
Associating JMS Resources with an MDB 16-19
State Diagram of an MDB 16-20
Developing MDBs 16-22
Interfaces to Be Implemented for MDBs 16-23
Implementing an MDB Class 16-24
Receiving Messages in an MDB Class 16-25
Creating the Deployment Descriptor 16-26
ejb-jar.xml: Example 16-28
Mapping in OC4J-Specific Deployment Descriptor 16-29
orion-ejb-jar.xml: Example 16-30
Creating an MDB with JDeveloper 16-31
Testing the MDB 16-34
Summary 16-35
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17 Integrating J2EE Components
Objectives 17-2
Overview 17-3
Creating Remote Clients for EJBs 17-4
Importing the EJB Home Interface 17-5
Create a Reference to the EJB 17-6
Passing Arguments to the EJB Method 17-7
Creating an EJB Reference 17-8
Creating Local Clients for EJBs 17-9
ejb-local-ref Element 17-10
EJB Tags 17-11
useHome Tag 17-12
useBean Tag 17-13
createBean Tag 17-14
iterate Tag 17-15
Using the EJB Tags 17-16
Deploying an Application: Web Tier 17-17
Deploying an Application: EJB Tier 17-18
Deploying an Application: EAR File 17-19
Deploying from Oracle Enterprise Manager 17-20
Summary 17-21
Practice 17-1 and 17-2: Overview 17-22
18 Distributing Modular Applications: Introduction to Web Services
Objectives 18-2
What Is a Web Service? 18-3
Web Service 18-4
Service-Oriented Architecture 18-6
Web Services Constituents 18-7
Benefits of Web Services 18-9
Web Services Model 18-11
RPC-Style Web Services 18-12
Document-Style Web Services 18-13
Oracle Support for Web Services 18-14
SOAP: XML Messaging for Web Services 18-15
Communication with SOAP 18-16
SOAP Messages 18-17
Web Services Description Language (WSDL) 18-19
WSDL 18-20
UDDI Registry 18-22
How UDDI Is Used 18-24
Searching for a Web Service by Using UDDI 18-25
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UDDI Specification 18-26
tModel 18-27
UDDI Support in Oracle JDeveloper 10g 18-31
UDDI Browsing with Oracle JDeveloper 10g 18-32
UDDI Publishing and Browsing with Oracle Enterprise Manager 18-33
Summary 18-34
Practice 18-1: Overview
19 Distributing Modular Applications: Developing Web Services
Objectives 19-2
Oracle Application Server 10g Web Services 19-3
Developing a Web Service with a Stateless Java Class 19-4
Defining an Interface 19-5
Defining a Stateless Java Class 19-7
Creating the Web Service 19-10
Creating the Client Application 19-11
Deploying the Web Service 19-13
Testing the Web Service 19-14
Web Service Home Page 19-15
Testing the Deployed Web Service with Home Page 19-16
Testing the sayHello Operation 19-17
Serializing and Encoding Parameters and Results 19-19
Developing a Stored Procedure Web Service 19-20
Generating Wrapper Classes Using JPublisher 19-21
Exposing a Function as a Web Service by Using Oracle JDeveloper 10g 19-22
Publishing the Package as a Web Service 19-23
JMS Web Services 19-24
Summary 19-26
Practice 19-1: Overview
20 Implementing Security in J2EE Applications
Objectives 20-2
Goals of J2EE Security Architecture 20-3
Overview of J2EE Security Architecture 20-4
Java Authentication and Authorization Service (JAAS) 20-5
Authorization of a Client 20-8
JAAS Provider Types in OC4J 20-9
Configuring Security 20-10
Defining the Users, Groups, and Roles 20-11
Managing Users and Groups with the JAZN Admintool 20-13
Defining the Logical Roles 20-15
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Defining and Using Logical Roles in Web Applications (web.xml) 20-16
Defining and Using Logical Roles in EJBs (ejb-jar.xml) 20-18
Mapping Logical Roles to Users and Groups 20-19
Programmatic Access to a Caller’s Security Context 20-20
Client Authentication 20-21
EJB Client Authentication with the jndi.properties file 20-22
EJB Client Authentication with a Hashtable 20-23
Setting Access Control with JDeveloper 20-24
Creating Web Application Security Roles 20-25
Web Application Login Authentication 20-26
Web Application Authorization 20-27
Creating EJB Security Roles 20-28
Setting Method Permissions 20-29
Method Access in EJB Deployment Descriptors 20-30
Creating a Mapping for the Logical Roles 20-31
Mapping JAZN Identities to a Logical Role 20-32
Mapping Results in orion-ejb-jar.xml 20-34
Accessing the EJB with New Permissions 20-35
Summary 20-36
Practice 20-1: Overview 20-37
21 Oracle Application Server 10g Transaction Support
Objectives 21-2
What Is a Transaction? 21-3
Enterprise JavaBeans (EJB) Support for Transactions 21-4
EJB Transaction Model 21-5
Demarcating Transactions 21-6
Container-Managed Transactions 21-7
CMT: Transaction Attributes 21-8
Transaction Attribute: NotSupported 21-10
Transaction Attribute: Required 21-11
Transaction Attribute: Supports 21-12
Transaction Attribute: RequiresNew 21-13
Transaction Attribute: Mandatory 21-14
Transaction Attribute: Never 21-15
CMT: The setRollbackOnly() Method 21-16
JDeveloper: Setting Transaction Attributes 21-17
Java Transaction API (JTA) 21-19
JTA: The UserTransaction Interface 21-20
Bean-Managed Transactions Demarcation 21-21
BMT Demarcation: Process 21-22
Using UserTransaction Support in EJBs 21-23
Client-Demarcated Transactions Using UserTransaction 21-24
BMT Demarcation: Restrictions 21-25
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Local and Global Transactions 21-26
Single-Phase Commit 21-27
Data Source Revisited 21-28
Default data-sources.xml 21-29
Emulated Versus Nonemulated Data Sources 21-30
Retrieve Connection to Data Source 21-31
Global Transaction Resource Request Flow 21-33
Resource Request Flow 21-34
Enlisting Database Resources 21-36
Summary 21-38
A Practice Solutions
B Schema Descriptions
C Oracle JDeveloper 10g Quick Reference
D BMP Entity EJBs J2EE Connector Architecture
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