JSTL Books

JSTL Books
— print (last updated: Nov 14, 2009) — print

This application has exactly the same behavior as that of Java Web Books. The JSP files are different in that they exclusively use tags to do everything — no "scripting" is used in any JSP file. As a consequence, other scripting-related features such as "page import" tags are no longer relevant.

You can either download the JSTLBooks.zip archive for use in NetBeans, or the file JSTLBooks.war for use in Eclipse. With NetBeans you must add the following JAR files into the Library; alternatively, install the MySQL, Hibernate, CommonsLang and JSTL libraries.

Hibernate essentials:
  antlr-2.7.6.jar
  commons-collections-3.2.1.jar
  dom4j-1.6.1.jar
  hibernate-core-3.3.1.GA.jar
  javassist-3.9.0.GA.jar
  jta-1.1.jar
  slf4j-api-1.5.8.jar
  slf4j-simple-1.5.8.jar
Commons/Lang:
  commons-lang-2.4.jar
MySQL JDBC Driver:
  mysql-connector-java-5.1.10-bin.jar
JSTL:
  jstl.jar
  standard.jar

Added Bean class

The JSTL & EL tags and function provide ways to replace every scripting detail used in Java Web Books except this code used to generate a book listing:

<%
   Session sess = db.getSession();
   Criteria crit = sess.createCriteria(Book.class);
   List<Book> books = crit.list();
%>

Although there are a number of possible solutions, we decide to add a new bean class:




models.Books


package models;

import java.util.*;
import org.hibernate.*;
import org.hibernate.criterion.Order;

public class Books {
  private DB db = new DB();
  private Order order = Order.asc("id");

  public void setOrderField(String field) {
    this.order = Order.asc(field);
  }

  public Books() {
  }

  public List<Book> getList() {
    Session sess = db.getSession();
    Criteria crit = sess.createCriteria(Book.class);
    crit.addOrder(order);
    List<Book> books = crit.list();
    return books;
  }
}

The Books class will provide a means of "hiding" the db bean which we have used throughout. The Books class, unlike the Hibernate ORM, is not meant to be a general purpose class for accessing the books table; it is simply a means for providing the functionality we need in order to avoid JSP scripting; it must be adapted as needed by the application.

The replacement for the above code becomes:

<jsp:useBean id="books" scope="session" class="models.Books" />
...
${books.list}  <!-- is the same as "books" in the previous version -->

Additionally, the Bean class is written is a way which allows the getList function to generate an "ordered" listing by virtue of the additional setOrderField function (ascending only).

The JSP files




nav.jsp


<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<table class="nav">
  <tr>
    <c:forEach var="entry" items="${nav.links}" >
      <td> <a href="${entry.key}">${entry.value}</a> </td>
    </c:forEach>
  </tr>
</table>





index.jsp


<%@ page contentType="text/html" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="f" uri="http://java.sun.com/jsp/jstl/functions" %>

<jsp:useBean id="books" scope="session" class="models.Books" />
<jsp:useBean id="nav" scope="session" class="util.Nav" />
<jsp:useBean id="cart" scope="session" class="java.util.HashMap" />
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd">

<c:set var="page_title" value="JSTL Books" />
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>${page_title}</title>
    <link rel="stylesheet" href="css/common.css" type="text/css" />
    <script type="text/javascript" src="js/jquery.js"></script>
    <script type="text/javascript" src="js/errors.js"></script>
    <script type="text/javascript" src="js/display.js"></script>
    <script type="text/javascript" src="js/cart.js"></script>
  </head>
  <body>
    <c:set target="${nav}" property="choice" value="ANON" />
    <%@ include file="nav.jsp" %>
    <h1>${page_title}</h1>
    <select id="sel">
      <option value="0">-- choose --</option>
      <c:set target="${books}" property="orderField" value="title" />
      <c:forEach var="book" items="${books.list}">
        <option value="${book.id}">${f:escapeXml(book.title)}</option>
      </c:forEach>
    </select>
    <br /><br />
    <div id="output">
      <table cellpadding="5px">
        <tr><td>id:</td> <td id="id"></td></tr>
        <tr><td>title:</td> <td id="title"></td></tr>
        <tr><td>type:</td> <td id="type"></td></tr>
        <tr><td>qty:</td> <td id="qty"></td></tr>
      </table>

      <button id="addtocart">Add To Cart</button>
    </div>
  </body>
</html>





cart.jsp


<%@ page contentType="text/html" pageEncoding="UTF-8"%>
<jsp:useBean id="cart" scope="session" class="java.util.HashMap" />
<jsp:useBean id="nav" scope="session" class="util.Nav" />

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

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd">
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>${page_title}</title>
    <link rel="stylesheet" href="css/common.css" type="text/css" />
  </head>
  <body>
    <c:set target="${nav}" property="choice" value="ANON" />
    <%@ include file="nav.jsp" %>
    <h1>${page_title}</h1>
    ${cart}
  </body>
</html>





admin.jsp


<%@ page contentType="text/html" pageEncoding="UTF-8"%>

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@ taglib prefix="f" uri="http://java.sun.com/jsp/jstl/functions" %>
<%@ taglib prefix="book" uri="/WEB-INF/booktags"%>

<jsp:useBean id="authadmin" scope="session" class="util.AuthInfo" />
<c:if test="${!authadmin.status}">
  <jsp:forward page="login.jsp" />
</c:if>

<!-- otherwise, basically the same as index.jsp, with a delete button
     added and the cart button removed
-->





login.jsp


<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>

<jsp:useBean id="authadmin" scope="session" class="util.AuthInfo" />
<jsp:useBean id="nav" scope="session" class="util.Nav" />
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd">

<c:set var="page_title" value="Login" />
<html>
  <head>
    <title>${page_title}</title>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <link rel="stylesheet" href="css/common.css" type="text/css" />
    <script type="text/javascript" src="js/jquery.js"></script>
    <script type="text/javascript" src="js/jquery.form.js"></script>
    <script type="text/javascript" src="js/errors.js"></script>
    <script type="text/javascript" src="js/login.js"></script>
  </head>
  <body>
    <c:set target="${nav}" property="choice" value="LOGIN" />
    <%@ include file="nav.jsp" %>
    <h1>${page_title}</h1>
    <form id="auth" action="Validate" autocomplete="off">
      Password: <input name="pwd" type="password" />
      <input type="submit" value="Enter" />
    </form>
  </body>
</html>





logout.jsp


<%@ page contentType="text/html" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<jsp:useBean id="authadmin" scope="session" class="util.AuthInfo" />
<c:set target="${authadmin}" property="status" value="false" />

<c:redirect url="." />





add.jsp


<%@ page contentType="text/html" pageEncoding="UTF-8"%>

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

<c:set var="page_title" value="Add A Book" />

<!-- There is little difference between this version and the 
     version in WebBooks
-->

JSTL Books — print (last updated: Nov 14, 2009) — print

Added Bean class

The JSP files

JSTL Books
— print (last updated: Nov 14, 2009) — print