Creating the View

The first file that the user navigates to is the view file Ch10_01.jsp. In this file, we use various custom Struts tags to implement the display you see in Example 10-1. For example, the <html:form> tag creates a Struts-enabled form that can display controls, as you see in Example 10-1; we're setting the form's action attribute to the name we'll give the controller, Ch10_04.do, so when the user clicks the Submit button (with the caption "Place your order"), the data in the form will be forwarded to the controller.

Example 10-1. A sample JSP
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="/WEB-INF/struts-bean.tld" prefix="bean" %>
<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
<%@ taglib uri="/WEB-INF/struts-logic.tld" prefix="logic" %>
<%@ taglib uri="/Ch10" prefix="Ch10" %>
<HTML>
 <HEAD>
 <TITLE>Here's the menu...</TITLE>
 </HEAD>
 <BODY>
 <H1>Here's the menu...</H1>
 <html:errors/>
 <Ch10:type/>
 <Ch10:items/>
 <html:form action="Ch10_04.do">
 <TABLE>
 <TR>
 <TD ALIGN="LEFT" VALIGN="TOP">
 <bean:message key="items"/>
 <BR>
 <logic:iterate >
 <html:multibox property="items">
 <%= items1 %>
 </html:multibox>
 <%= items1 %>
 <BR>
 </logic:iterate>
 </TD>
 <TD ALIGN="LEFT" VALIGN="TOP">
 <bean:message key="type"/>
 <BR>
 <html:select property="type">
 <html:options />
 </html:select>
 </TD>
 </TR>
 <TR>
 <TD ALIGN="LEFT">
 <BR>
 <bean:message key="email"/>
 <html:text property="email"/>
 </TD>
 <TR>
 </TABLE>
 <BR>
 <html:submit value="Place your order"/>
 </html:form>
 </BODY>
</HTML>


Create this file by right-clicking the deployment folder in Eclipse and selecting New Screenshot File, which automatically stores Ch10_01.jsp in the webapps/Ch10_01 folder. As you see in Screenshot-1, the drop-down list we're presenting holds the items Pizza, Calzone, and Sandwich, and you can see the list of ingredients—Sausage, Cheese, Pepperoni, Meatballs, and Peppers—represented with a list of checkboxes. To make the items in these lists available to Struts HTML control in the view, we'll use two custom JSP tags, <Ch10:type> to return items like Pizza and Calzone, and <Ch10:items> to return items like Sausage, Cheese, and Pepperoni. As you can see in Example 10-1, we use the Struts <logic:iterate>, <html:multibox>, and <html:options> tags to create the needed HTML controls from those lists of items. You can see the implementation of these custom tags in Example 10-2 and Example 10-3. In Eclipse, create these files and store them in the src folder by right-clicking that folder and selecting NewScreenshot Class, placing the new classes, Ch10_02 and Ch10_03, in the org.eclipsebook.ch10 package.

Example 10-2. A custom tag class for order types
package org.eclipsebook.ch10;
import javax.servlet.jsp.tagext.TagSupport;
public class Ch10_02 extends TagSupport {
 public int doStartTag( ) {
 String[] typeArray = {"", "Pizza", "Calzone", "Sandwich"};
 pageContext.setAttribute("type", typeArray);
 return SKIP_BODY;
 }
}


Example 10-3. A custom tag class for pizza toppings
package org.eclipsebook.ch10;
import javax.servlet.jsp.tagext.TagSupport;
public class Ch10_03 extends TagSupport {
 public int doStartTag( ) {
 String[] itemsArray = {"Sausage", "Cheese", "Pepperoni", "Meatballs", "Peppers"};
 pageContext.setAttribute("items", itemsArray);
 return SKIP_BODY;
 }
}


To make these custom tags work, we need a tag library descriptor file, which you can see in Example 10-4. This file goes into deployment\WEB-INF.

Example 10-4. The TLD for the custom tags
<?xml version="1.0"?>
<!DOCTYPE taglib PUBLIC "-//Oracle//DTD JSP Tag Library 1.1//EN"
 "http://java.oracle.com/j2ee/dtds/web-jsptaglibrary_1_1.dtd">
<taglib>
 <tlibversion>1.0</tlibversion>
 <jspversion>1.2</jspversion>
 <shortname>StrutsExample</shortname>
 <info>
 Supports the Struts Example
 </info>
 <tag>
 <name>type</name>
 <tagclass>org.eclipsebook.ch10.Ch10_02</tagclass>
 <bodycontent>empty</bodycontent>
 </tag>
 <tag>
 <name>items</name>
 <tagclass>org.eclipsebook.ch10.Ch10_03</tagclass>
 <bodycontent>JSP</bodycontent>
 </tag>
</taglib>
      
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