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    Head First Servlets and JSP™
    Dedication
    A Note Regarding Supplemental Files
    Praise for Head First Servlets and JSP™
    Praise for the Head First approach
    Perpetrators of the Head First series (and this book)
    How to Use this Book: Intro
    1. Intro and Overview: Why use Servlets & JSPs?
    2. High-Level Overview: Web App Architecture
    3. Hands-on MVC: Mini MVC Tutorial
    4. Request and Response: Being a Servlet
    5. Attributes and Listeners: Being a Web App
    6. Session Management: Conversational state
    7. Using JSP: Being a JSP
    8. Scriptless JSP: Script-free pages
    9. Using JSTL: Custom tags are powerful
    EL and standard actions are limited
    The case of the disappearing HTML (reprised)
    There’s a better way: use the <c:out> tag
    Null values are rendered as blank text
    Set a default value with the default attribute
    Looping without scripting
    <c:forEach>
    Deconstructing <c:forEach>
    You can even nest <c:forEach> tags
    Doing a conditional include with <c:if>
    But what if you need an else?
    The <c:if> tag won’t work for this
    The <c:choose> tag and its partners <c:when> and <c:otherwise>
    The <c:set> tag... so much cooler than <jsp:setProperty>
    Using <c:set> with beans and Maps
    Key points and gotchas with <c:set>
    <c:remove> just makes sense
    With <c:import>, there are now THREE ways to include content
    <c:import> can reach OUTSIDE the web app
    Customizing the thing you include
    Doing the same thing with <c:param>
    <c:url> for all your hyperlink needs
    What if the URL needs encoding?
    You do NOT want your clients to see this:
    Make your own error pages
    Configuring error pages in the DD
    Error pages get an extra object: exception
    The <c:catch> tag. Like try/catch...sort of
    You can make the exception an attribute
    What if you need a tag that’s NOT in JSTL?
    Using a tag library that’s NOT from the JSTL
    Making sense of the TLD
    Using the custom “advice” tag
    The custom tag handler
    Pay attention to <rtexprvalue>
    <rtexprvalue> is NOT just for EL expressions
    What can be in a tag body
    The tag handler, the TLD, and the JSP
    The taglib <uri> is just a name, not a location
    The Container builds a map
    Four places the Container looks for TLDs
    When a JSP uses more than one tag library
    Coffee Cram: Mock Exam Chapter 9
    Coffee Cram: Chapter 9 Answers
    10. Custom Tag Development: When even JSTL is not enough...
    11. Web App Deployment: Deploying your web app
    12. Web App Security: Keep it secret, keep it safe
    13. Filters and Wrappers: The Power of Filters
    14. Patterns and Struts: Enterprise Design Patterns
    A. Final Mock Exam: Coffee Cram
    B.
    C.
    Index
    About the Authors
    Copyright
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    9. Using JSTL: Custom tags are powerful > When a JSP uses more than one tag lib...

    When a JSP uses more than one tag library

    If you want to use more than one tag library in a JSP, do a separate taglib directive for each TLD. There a few issues to keep in mind...

    • Make sure the taglib uri names are unique. In other words, don’t put in more than one directive with the same uri value.

    • Do NOT use a prefix that’s on the reserved list. The reserved prefixes are:

      jsp:

      jspx:

      java:

      javax:

      servlet:

      sun:

      sunw:

    Sharpen your pencil

    Empty tags

    Write in examples of the THREE different ways to invoke a tag that must have an empty body.

    (Check your answers by looking back through the chapter. No, we’re not going to tell you the page number.)

    1. __________________________________________________________________

    2. __________________________________________________________________

    3. __________________________________________________________________

    Sharpen your pencil

    How the JSP, the TLD, and the bean attribute class relate

    Fill in the spaces based on the information that you can see in the TLD. Draw arrows to indicate where the different pieces of information are tied together. In other words, for each blank, show exactly where you found the information needed to fill in the blank.

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    Sharpen your pencil

    Test your Tag memory ANSWERS

    1. Fill in the name of the optional attribute.

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    2. Fill in the missing attribute name.

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    3. Fill in the missing attribute name.

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      Note

      The <c:set> tag must have a value, but you could choose to put the value in the body of the tag instead of as an attribute.

    4. Fill in the missing tag names (two different tag types), and the missing attribute name.

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    Sharpen your pencil

    How the JSP, the TLD, and the bean attribute class relate ANSWERS

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