jsptags7.html

j2eePDF格式的电子书

</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90754"> </a><div class="pCellBody">
<code class="cCode">/bookdetails</code>
</div>
</td>
    <td><a name="wp90756"> </a><div class="pCellBody">
<code class="cCode">Book Description</code>
</div>
</td>
    <td><a name="wp90758"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90760"> </a><div class="pCellBody">
<code class="cCode">/bookdetails.jsp</code>
</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90762"> </a><div class="pCellBody">
<code class="cCode">/bookshowcart</code>
</div>
</td>
    <td><a name="wp90764"> </a><div class="pCellBody">
<code class="cCode">Shopping Cart</code>
</div>
</td>
    <td><a name="wp90766"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90768"> </a><div class="pCellBody">
<code class="cCode">/bookshowcart.jsp</code>
</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90770"> </a><div class="pCellBody">
<code class="cCode">/bookcashier</code>
</div>
</td>
    <td><a name="wp90772"> </a><div class="pCellBody">
<code class="cCode">Cashier</code>
</div>
</td>
    <td><a name="wp90774"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90776"> </a><div class="pCellBody">
<code class="cCode">/bookcashier.jsp</code>
</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90778"> </a><div class="pCellBody">
<code class="cCode">/bookreceipt</code>
</div>
</td>
    <td><a name="wp90780"> </a><div class="pCellBody">
<code class="cCode">Receipt</code>
</div>
</td>
    <td><a name="wp90782"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90784"> </a><div class="pCellBody">
<code class="cCode">/bookreceipt.jsp</code>
</div>
</td>
</tr>
</table>
</div>
<p class="pBody">.
</p>
<a name="wp90785"> </a><p class="pBody">
If the URL passed in the request is /<code class="cCode">bookstore</code>, the <code class="cCode">Definition</code> contains the items from the first row of <a  href="JSPTags7.html#wp90722">Table 15-14</a>:</p><div align="left">
<table border="1" summary="Definition for URL /enter" id="wp90792">
  <caption><a name="wp90792"> </a><div class="pTableTitle">
Table 15-15   Definition for URL /bookstore
</div>
</caption>
  <tr align="center">    <th><a name="wp90798"> </a><div class="pCellHeading">
Title
</div>
</th>
    <th><a name="wp90800"> </a><div class="pCellHeading">
Banner
</div>
</th>
    <th><a name="wp90802"> </a><div class="pCellHeading">
Body
</div>
</th>
</tr>
  <tr align="left">    <td><a name="wp90804"> </a><div class="pCellBody">
<code class="cCode">Duke's Bookstore</code>
</div>
</td>
    <td><a name="wp90806"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90808"> </a><div class="pCellBody">
<code class="cCode">/bookstore.jsp</code>
</div>
</td>
</tr>
</table>
</div>
<p class="pBody">
</p>
<a name="wp90812"> </a><p class="pBody">
The parameters for the URL <code class="cCode">/bookstore</code> are shown in <a  href="JSPTags7.html#wp90820">Table 15-16</a>. The parameters specify that the value of the <code class="cCode">title</code> parameter, Duke's Bookstore, should be inserted directly into the output stream, but the values of <code class="cCode">banner</code> and <code class="cCode">body</code> should be dynamically included.</p><div align="left">
<table border="1" summary="Screen Definition for URL /enter" id="wp90820">
  <caption><a name="wp90820"> </a><div class="pTableTitle">
Table 15-16   Parameters for the URL /bookstore&nbsp;
</div>
</caption>
  <tr align="center">    <th><a name="wp90826"> </a><div class="pCellHeading">
Parameter Name
</div>
</th>
    <th><a name="wp90828"> </a><div class="pCellHeading">
Parameter Value
</div>
</th>
    <th><a name="wp90830"> </a><div class="pCellHeading">
isDirect
</div>
</th>
</tr>
  <tr align="left">    <td><a name="wp90832"> </a><div class="pCellBody">
<code class="cCode">title</code>
</div>
</td>
    <td><a name="wp90834"> </a><div class="pCellBody">
<code class="cCode">Duke's Bookstore</code>
</div>
</td>
    <td><a name="wp90836"> </a><div class="pCellBody">
<code class="cCode">true</code>
</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90838"> </a><div class="pCellBody">
<code class="cCode">banner</code>
</div>
</td>
    <td><a name="wp90840"> </a><div class="pCellBody">
<code class="cCode">/banner.jsp</code>
</div>
</td>
    <td><a name="wp90842"> </a><div class="pCellBody">
<code class="cCode">false</code>
</div>
</td>
</tr>
  <tr align="left">    <td><a name="wp90844"> </a><div class="pCellBody">
<code class="cCode">body</code>
</div>
</td>
    <td><a name="wp90846"> </a><div class="pCellBody">
<code class="cCode">/bookstore.jsp</code>
</div>
</td>
    <td><a name="wp90848"> </a><div class="pCellBody">
<code class="cCode">false</code>
</div>
</td>
</tr>
</table>
</div>
<p class="pBody">
</p>
<a name="wp90850"> </a><p class="pBody">
<code class="cCode"><a  href="../examples/web/bookstore3/src/template/InsertTag.java" target="_blank">InsertTag</a></code> inserts parameters of the screen definition into the response. In the <code class="cCode">doTag</code> method, it retrieves the definition object from the page context and then inserts the parameter value. If the parameter is direct, it is directly inserted into the response; otherwise, the request is sent to the parameter, and the response is dynamically included into the overall response.
</p>
<div class="pPreformattedRelative"><pre class="pPreformattedRelative">
public void doTag() throws JspTagException {&nbsp;&nbsp;
&nbsp;&nbsp;Definition definition = null;
&nbsp;&nbsp;Parameter parameter = null;
&nbsp;&nbsp;boolean directInclude = false;
&nbsp;&nbsp;PageContext context = (PageContext)getJspContext();

&nbsp;&nbsp;&nbsp;&nbsp;// get the definition from the page context
&nbsp;&nbsp;definition = (Definition)context.getAttribute(
&nbsp;&nbsp;&nbsp;&nbsp;definitionName, context.APPLICATION_SCOPE);
&nbsp;&nbsp;&nbsp;&nbsp;// get the parameter
&nbsp;&nbsp;if (parameterName != null &amp;&amp; definition != null)
&nbsp;&nbsp;&nbsp;&nbsp;parameter = (Parameter)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;definition.getParam(parameterName);

&nbsp;&nbsp;if (parameter != null)
&nbsp;&nbsp;&nbsp;&nbsp;directInclude = parameter.isDirect();

&nbsp;&nbsp;try {
&nbsp;&nbsp;&nbsp;&nbsp;// if parameter is direct, print to out
&nbsp;&nbsp;&nbsp;&nbsp;if (directInclude &amp;&amp; parameter  != null)
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;context.getOut().print(parameter.getValue());
&nbsp;&nbsp;&nbsp;&nbsp;// if parameter is indirect, 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;include results of dispatching to page 
&nbsp;&nbsp;&nbsp;&nbsp;else {
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if ((parameter != null) &amp;&amp; 
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(parameter.getValue() !=  null))
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;context.include(parameter.getValue());
&nbsp;&nbsp;&nbsp;&nbsp;}
&nbsp;&nbsp;} catch (Exception ex) {
&nbsp;&nbsp;&nbsp;&nbsp;  throw new JspTagException(ex.getMessage());
&nbsp;&nbsp;}
}<a name="wp90851"> </a>
<a name="wp86950"> </a><p class="pBodyRelative">

</p>
</pre></div>
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