Document Information

Preface

Part I Introduction

1.  Overview

2.  Using the Tutorial Examples

Part II The Web Tier

3.  Getting Started with Web Applications

4.  Java Servlet Technology

5.  JavaServer Pages Technology

6.  JavaServer Pages Documents

7.  JavaServer Pages Standard Tag Library

The Example JSP Pages

Core Tag Library

Variable Support Tags

Flow Control Tags in the Core Tag Library

Conditional Tags

Iterator Tags

URL Tags

Miscellaneous Tags

XML Tag Library

Core Tags

XML Flow Control Tags

Transformation Tags

Internationalization Tag Library

Setting the Locale

Messaging Tags

The setBundle and bundle Tags

The message Tag

Formatting Tags

SQL Tag Library

query Tag Result Interface

JSTL Functions

Further Information about JSTL

8.  Custom Tags in JSP Pages

9.  Scripting in JSP Pages

10.  JavaServer Faces Technology

11.  Using JavaServer Faces Technology in JSP Pages

12.  Developing with JavaServer Faces Technology

13.  Creating Custom UI Components

14.  Configuring JavaServer Faces Applications

15.  Internationalizing and Localizing Web Applications

Part III Web Services

16.  Building Web Services with JAX-WS

17.  Binding between XML Schema and Java Classes

18.  Streaming API for XML

19.  SOAP with Attachments API for Java

Part IV Enterprise Beans

20.  Enterprise Beans

21.  Getting Started with Enterprise Beans

22.  Session Bean Examples

23.  A Message-Driven Bean Example

Part V Persistence

24.  Introduction to the Java Persistence API

25.  Persistence in the Web Tier

26.  Persistence in the EJB Tier

27.  The Java Persistence Query Language

Part VI Services

28.  Introduction to Security in the Java EE Platform

29.  Securing Java EE Applications

30.  Securing Web Applications

31.  The Java Message Service API

32.  Java EE Examples Using the JMS API

33.  Transactions

34.  Resource Connections

35.  Connector Architecture

Part VII Case Studies

36.  The Coffee Break Application

37.  The Duke's Bank Application

Part VIII Appendixes

A.  Java Encoding Schemes

B.  About the Authors

Index

 

Using JSTL

JSTL includes a wide variety of tags that fit into discrete functional areas. To reflect this, as well as to give each area its own namespace, JSTL is exposed as multiple tag libraries. The URIs for the libraries are as follows:

  • Core: http://java.sun.com/jsp/jstl/core

  • XML: http://java.sun.com/jsp/jstl/xml

  • Internationalization: http://java.sun.com/jsp/jstl/fmt

  • SQL: http://java.sun.com/jsp/jstl/sql

  • Functions: http://java.sun.com/jsp/jstl/functions

Table 7-1 summarizes these functional areas along with the prefixes used in this tutorial.

Table 7-1 JSTL Tags

Area

Subfunction

Prefix

Core

Variable support

c

Flow control

URL management

Miscellaneous

XML

Core

x

Flow control

Transformation

I18N

Locale

fmt

Message formatting

Number and date formatting

Database

SQL

sql

Functions

Collection length

fn

String manipulation

Thus, the tutorial references the JSTL core tags in JSP pages by using the following taglib directive:

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

In addition to declaring the tag libraries, tutorial examples access the JSTL API and implementation. In the Application Server, the JSTL TLDs and libraries are distributed in the archive as-install/lib/appserv-jstl.jar. This library is automatically loaded into the classpath of all web applications running on the Application Server, so you don’t need to add it to your web application.

Tag Collaboration

Tags usually collaborate with their environment in implicit and explicit ways. Implicit collaboration is done by means of a well-defined interface that allows nested tags to work seamlessly with the ancestor tag that exposes that interface. The JSTL conditional tags employ this mode of collaboration.

Explicit collaboration happens when a tag exposes information to its environment. JSTL tags expose information as JSP EL variables; the convention followed by JSTL is to use the name var for any tag attribute that exports information about the tag. For example, the forEach tag exposes the current item of the shopping cart it is iterating over in the following way:

<c:forEach var="item" items="${sessionScope.cart.items}">
    ...
</c:forEach>

In situations where a tag exposes more than one piece of information, the name var is used for the primary piece of information being exported, and an appropriate name is selected for any other secondary piece of information exposed. For example, iteration status information is exported by the forEach tag through the attribute status.

When you want to use an EL variable exposed by a JSTL tag in an expression in the page’s scripting language (see Chapter 9, Scripting in JSP Pages), you use the standard JSP element jsp:useBean to declare a scripting variable.

For example, tut-install/javaeetutorial5/examples/web/bookstore4/web/books/bookshowcart.jsp removes a book from a shopping cart using a scriptlet. The ID of the book to be removed is passed as a request parameter. The value of the request parameter is first exposed as an EL variable (to be used later by the JSTL sql:query tag) and then is declared as a scripting variable and passed to the cart.remove method:

<c:set var="bookId" value="${param.Remove}"/>
<jsp:useBean id="bookId" type="java.lang.String" />
<% cart.remove(bookId); %>
<sql:query var="books"
     dataSource="${applicationScope.bookDS}">
    select * from PUBLIC.books where id = ?
    <sql:param value="${bookId}" />
</sql:query>