Document Information


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

8.  Custom Tags in JSP Pages

9.  Scripting in JSP Pages

10.  JavaServer Faces Technology

11.  Using JavaServer Faces Technology in JSP Pages

The Example JavaServer Faces Application

Setting Up a Page

Using the Core Tags

Adding UI Components to a Page Using the HTML Component Tags

UI Component Tag Attributes

The id Attribute

The immediate Attribute

The rendered Attribute

The style and styleClass Attributes

The value and binding Attributes

Adding a Form Component

Using Text Components

Rendering a Text Field with the inputText Tag

Rendering a Label with the outputLabel Tag

Rendering a Hyperlink with the outputLink Tag

Displaying a Formatted Message with the outputFormat Tag

Rendering a Password Field with the inputSecret Tag

Using Command Components for Performing Actions and Navigation

Rendering a Button with the commandButton Tag

Rendering a Hyperlink with the commandLink Tag

Using Data-Bound Table Components

Adding Graphics and Images with the graphicImage Tag

Laying Out Components with the UIPanel Component

Rendering Components for Selecting One Value

Displaying a Check Box Using the selectBooleanCheckbox Tag

Displaying a Menu Using the selectOneMenu Tag

Rendering Components for Selecting Multiple Values

The UISelectItem, UISelectItems, and UISelectItemGroup Components

Using the selectItems Tag

Using the selectItem Tag

Displaying Error Messages with the message and messages Tags

Using Localized Data

Loading a Resource Bundle

Referencing Localized Static Data

Referencing Error Messages

Using the Standard Converters

Converting a Component's Value

Using DateTimeConverter

Using NumberConverter

Registering Listeners on Components

Registering a Value-Change Listener on a Component

Registering an Action Listener on a Component

Binding Component Values and Instances to External Data Sources

Binding a Component Value to a Property

Binding a Component Value to an Implicit Object

Binding a Component Instance to a Bean Property

Binding Converters, Listeners, and Validators to Backing Bean Properties

Referencing a Backing Bean Method

Referencing a Method That Performs Navigation

Referencing a Method That Handles an Action Event

Referencing a Method That Performs Validation

Referencing a Method That Handles a Value-change Event

Using Custom Objects

Using a Custom Converter

Using a Custom Validator

Using a Custom Component

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



Using the Standard Validators

JavaServer Faces technology provides a set of standard classes and associated tags that page authors and application developers can use to validate a component’s data. Table 11-7 lists all the standard validator classes and the tags that allow you to use the validators from the page.

Table 11-7 The Validator Classes

Validator Class





Checks whether the local value of a component is within a certain range. The value must be floating-point or convertible to floating-point.



Checks whether the length of a component’s local value is within a certain range. The value must be a java.lang.String.



Checks whether the local value of a component is within a certain range. The value must be any numeric type or String that can be converted to a long.

All these validator classes implement the Validator interface. Component writers and application developers can also implement this interface to define their own set of constraints for a component’s value.

Similarly to the standard converters, each of these validators has one or more standard error messages associated with it. If you have registered one of these validators onto a component on your page, and the validator is not able to validate the component’s value, the validator’s error message will display on the page. For example, the error message that displays when the component’s value exceeds the maximum value allowed by LongRangeValidator is the following:

{1}: Validation Error: Value is greater than allowable maximum of "{0}"

In this case the {1} substitution parameter is replaced by the component’s label or ID, and the {0} substitution parameter is replaced with the maximum value allowed by the validator.

See section 2.5.4 of the JavaServer Faces specification for the complete list of error messages. See Displaying Error Messages with the message and messages Tags for information on how to display validation error messages on the page when validation fails.

Validating a Component’s Value

In order to validate a component’s value using a particular validator, you need to register the validator on the component. You have three ways to do this:

  • Nest the validator’s corresponding tag (shown in Table 11-7) inside the component’s tag. Using the LongRangeValidator describes how to use the validateLongRange tag. You can use the other standard tags in the same way.

  • Refer to a method that performs the validation from the component tag’s validator attribute.

  • Nest a validator tag inside the component tag and use either the validator tag’s validatorId attribute or its binding attribute to refer to the validator.

See Referencing a Method That Performs ValidationReferencing a Method That Performs Validation for more information on using the validator attribute.

The validatorId attribute works similarly to the converterId attribute of the converter tag, as described in Converting a Component's Value. See Binding Converters, Listeners, and Validators to Backing Bean Properties for more information on using the binding attribute of the validator tag.

Keep in mind that validation can be performed only on components that implement EditableValueHolder because these components accept values that can be validated.

Using the LongRangeValidator

The Duke’s Bookstore application uses a validateLongRange tag on the quantity input field of the bookshowcart.jsp page:

<h:inputText id="quantity" size="4"
" >
    <f:validateLongRange minimum="1"/>
<h:message for="quantity"/>

This tag requires that the user enter a number that is at least 1. The size attribute specifies that the number can have no more than four digits. The validateLongRange tag also has a maximum attribute, with which you can set a maximum value of the input.

The attributes of all the standard validator tags accept value expressions. This means that the attributes can reference backing bean properties rather than specify literal values. For example, the validateLongRange tag in the preceding example can reference a backing bean property called minimum to get the minimum value acceptable to the validator implementation:

<f:validateLongRange minimum="#{ShowCartBean.minimum}" />