Tuesday, May 15, 2012

JSP Expression Language (EL)


Expression Language

A primary feature of JSP technology version 2.0 is its support for an expression language (EL). An expression language makes it possible to easily access application data stored in JavaBeans components
Expression language is, both syntactically and semantically, similar to JavaScript expressions.
  • There is no typecasting
  • Type conversions are usually done implicitly
  • Double and single quotes are equivalent
  • object.property has the same meaning as object['property']
                              The general syntax : ${var| object.var}

Example

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<!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>Expression Language</title>
</head>
<body> 
            ${ 2+5 }
</body>
</html>

output : 7

Implicit Objects

The JSP expression language defines a set of implicit objects:
  • pageContext: The context for the JSP page. Provides access to various objects including:

    • servletContext: The context for the JSP page’s servlet and any web components contained in the same application.

    • session: The session object for the client.

    • request: The request triggering the execution of the JSP page.

    • response: The response returned by the JSP page.
       
In addition, several implicit objects are available that allow easy access to the following objects:
  • param: Maps a request parameter name to a single value

  • paramValues: Maps a request parameter name to an array of values

  • header: Maps a request header name to a single value

  • headerValues: Maps a request header name to an array of values

  • cookie: Maps a cookie name to a single cookie

  • initParam: Maps a context initialization parameter name to a single value
Finally, there are objects that allow access to the various scoped variables
  • pageScope: Maps page-scoped variable names to their values

  • requestScope: Maps request-scoped variable names to their values

  • sessionScope: Maps session-scoped variable names to their values

  • applicationScope: Maps application-scoped variable names to their values
Example :

                   (param - Maps a request parameter name to a single value)

one.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<!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>login</title>
</head>
<body>
       <form action="display.jsp">
              Enter the name : <input type="text" name="email"> 
                                        <input type="submit" value="Enter">
       </form>
</body>
</html>

display.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<!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>Expression Language</title>
</head>
        <body>
                  Your email id :${param['email'] }
                  <br><br>
                  Your email id :${param.email}
       </body>
</html>
           (paramValues: Maps a request parameter name to an array of values)

Login.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<!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>login</title>
</head>
          <body>
                   <form action="paramvalues.jsp">
                         Username: <input type="text" name="uname" /><br>
                         Password: <input type="password" name="password" />
                                         <input type="submit" value="Enter" />
                   </form>
         </body>
</html>

paramValues.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Expression Language</title>
</head>
<body>
           <c:forEach var="params" items="${paramValues}">
            <c:out value="${params.key}"></c:out> :
             <c:forEach var="value" items="${params.value }">
             <c:out value="${value}"></c:out>
            <br>
           </c:forEach>
           </c:forEach>
</body>
</html>


Operators
In addition to the . And [] operators discussed in Value and Method Expressions, the JSP expression language provides the following operators, which can be used in value expressions only:
  • Arithmetic: +,-(binary),*,/and div, % and mod, -(unary)

  • Logical: and, &&, or, ||, not, !

  • Relational: ==,eq,!=,ne,<,lt,>,gt,<=,ge,>=,le. Comparisons can be made against other values, or against boolean, string, integer, or floating point literals.

  • Empty: The empty operator is a prefix operation that can be used to determine whether a value is null or empty.

  • Conditional:  A?B:C. Evaluate B or C, depending on the result of the evaluation of A.
The precedence of operators highest to lowest, left to right is as follows:
  • [] .
  • ()(used to change the precedence of operators)
  • -(unary)not ! empty
  • * / div % mod
  • + -(binary)
  • < > <= >= lt gt le ge
  • == != eq ne
  • && and
  • || or
  • ? :

Reserved Words

The following words are reserved for the JSP expression language and should not be used as identifiers.

And
or
not
eq
ne
lt
gt
le
ge
true
false
null
instanceof
empty
div
mod

Operators & Reserved Words - Example:

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Expression Language</title>
</head>
<body>
<pre>
           The sum of (2 + 3) : ${ 2 + 3 }<br>
           The result of (2 > 3) : ${ 2 gt 3 }<br>
           The result of (55 % 8) : ${ 55 mod 8}
</pre>
</body>
</html>


JSTL (JavaServer Pages Tag Library)
JSTL includes a wide variety of tags that fit into discrete functional areas. To reflect this, as well as to give each area its own namespace, JSTL is exposed as multiple tag libraries.
The URIs for the libraries are as follows:
  • Core:
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
  • XML:
<%@ taglib prefix="x" uri="http://java.sun.com/jsp/jstl/xml" %>
  • Internationalization:
<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt" %>
  • SQL:
<%@ taglib prefix="sql" uri="http://java.sun.com/jsp/jstl/sql" %>
  • Functions:
<%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %>

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

Tag Summary
catch
Catches any Throwable that occurs in its body and optionally exposes it.
choose
Simple conditional tag that establishes a context for mutually exclusive conditional operations, marked by <when> and <otherwise>
if
Simple conditional tag, which evalutes its body if the supplied condition is true and optionally exposes a Boolean scripting variable representing the evaluation of this condition
import
Retrieves an absolute or relative URL and exposes its contents to either the page, a String in 'var', or a Reader in 'varReader'.
forEach
The basic iteration tag, accepting many different collection types and supporting subsetting and other functionality
forTokens
Iterates over tokens, separated by the supplied delimeters
out
Like <%= ... >, but for expressions.
otherwise
Subtag of <choose> that follows <when> tags and runs only if all of the prior conditions evaluated to 'false'
param
Adds a parameter to a containing 'import' tag's URL.
redirect
Redirects to a new URL.
remove
Removes a scoped variable (from a particular scope, if specified).
set
Sets the result of an expression evaluation in a 'scope'
url
Creates a URL with optional query parameters.
when
Subtag of <choose> that includes its body if its condition evalutes to 'true'


<c:out> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>JSTL Example</title>
</head>
<body>
           <c:out value="welcome"></c:out>
           <br> The sum is : <c:out value="${ 2 + 5 }"></c:out>
</body>
</html>
<c:import> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Index File</title>
</head>
<body>
<h4>Message!</h4>
         <c:import url="/viewMessage.jsp"></c:import>
</body>
</html>
<c:if> Example
index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<!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>Index File</title>
</head>
<body>
<form action="expression.jsp">
              Enter the A value :<input type="text" name="a"><br>
              Enter the B value :<input type="text" name="b"><br>
            
             <input type="submit" value="sum" name="operator">
             <input type="submit" value="sub" name="operator">
             <input type="submit" value="mul" name="operator">
</form>
</body>
</html>
expression.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>JSTL Example</title>
</head>
<body>
         <c:if test="${param.operator eq 'sum' }">
                           The sum is :${param.a + param.b}
          </c:if>

          <c:if test="${param.operator eq 'sub' }">
                           The sub is :${param.a - param.b}
           </c:if>
 
            <c:if test="${param.operator eq 'mul' }">
                               The mul is :${param.a * param.b}
            </c:if>
</body>
</html>

<c:forEach> Example1

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Expression Language</title>
</head>
<body>
           <c:forEach var="data" begin="1" end="10" step="1">
           <c:out value="${data}"></c:out>
           <br>
</c:forEach>
</body>
</html>

Example 2

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/emp")
public class Employee extends HttpServlet {
 private static final long serialVersionUID = 1L;

 public Employee() {
  super();
 }

 protected void doGet(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {
  List list = new ArrayList();
  list.add("Manoj");
  list.add("Krish");
  list.add("Rajesh");
  list.add("Balaji");
  request.setAttribute("emp", list);
  RequestDispatcher rd = request.getRequestDispatcher("viewNames.jsp");
  rd.forward(request, response);
 }

 protected void doPost(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {
  doGet(request, response);
 }
}
viewNames.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>JSTL Example</title>
</head>
<body>
                    <h3>Employee Names are :</h3>
                   <table border="2">
                               <tr><th>Names</th></tr>
                                      <c:forEach items="${emp}" var="name">
                                                  <tr><td><c:out value="${name}"></c:out></td></tr>
                                       </c:forEach>
</table>
</body>
</html>
<c:forToken> Examples
Example 1
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Expression Language</title>
</head>
<body>
           <c:forTokens items="lakshman,krish,balu,jsltech,manoj" delims=","
var="name">
<c:out value="${name}"></c:out>
<br>
</c:forTokens>
</body>
</html>

Example 2
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>JSTL Example</title>
</head>
<body>
<c:forTokens items="${names}" delims="," var="name">
<c:out value="${name}"></c:out>
<br>
</c:forTokens>
</body>
</html>

<c:when><c:choose> Example
index.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!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>Index File</title>
</head>
<body>
<form action="viewGrade.jsp">
Enter the salary :<input type="text" name="salary"><input
type="submit" value="Enter">
</form>
</body>
</html>
viewGrade.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>JSTL Example</title>
</head>
<body>
<c:choose>
                    <c:when test="${param.salary gt 50000 }">
                                 <c:out value="A Grade Employee"></c:out>
                    </c:when>
                     
                    <c:when test="${param.salary gt 30000 }">
                              <c:out value="B Grade Employee"></c:out>
                   </c:when>
 
                  <c:when test="${param.salary gt 15000 }">
                               <c:out value="C Grade Employee"></c:out>
                   </c:when>
<c:otherwise>
 
                   <c:out value="He doesn't have any grade"></c:out>

</c:otherwise>
</c:choose>

</body>
</html>

<c:set> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8" isELIgnored="false"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Expression Language</title>
</head>
<body>
            <c:set var="message" value="Welcome to JSTL Tech" scope="page"></c:set>
            <c:out value="${message}"></c:out>
</body>
</html>
<c:url> Example
index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Index File</title>
</head>
<body>
      <c:set var="names"
           value="Hari,Krish,Balu,Ramesh,Rajesh Babu,RamaKrishna" 
           scope="session">
       </c:set>
        <a href='<c:url value="/viewNames.jsp"></c:url>'>view Names</a>
</body>
</html>
viewNames.jsp

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

<!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>Expression Language</title>
</head>
<body>
            <c:forTokens items="${names}" delims="," var="name">
            <c:out value="${name}"></c:out>
<br>
</c:forTokens>
</body>
</html>
<c:import> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Index File</title>
</head>
<body>
<h4>Message!</h4>
          <c:import url="/viewMessage.jsp"></c:import>
</body>
</html>
viewMessage.jsp

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<font color="green"><c:out value="Welcome to JSL Tech"></c:out></font>
<c:remove> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Index File</title>
</head>
<body>
          <c:set value="JSL Tech" scope="page" var="message"></c:set>
Before Removing :
          <c:out value="${message}"></c:out>
<br>
          <c:remove var="message" scope="page" />
After Removing :
          <c:out value="${message}"></c:out>
<br>
</body>
</html>
<c:param> Example
index.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Index File</title>
</head>
<body>
                    <c:url value="/welcome.jsp" var="myUrl">
                           <c:param name="name" value="JSLTech" />
                          <c:param name="email" value="lakshman.miani@gmail.com" />
                    </c:url>
 
                    <a href="${myUrl}">ClickHere</a>
</body>
</html>
welcome.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Welcome Page</title>
</head>
<body>
        User name :
                           <c:out value="${param.name}"></c:out>
<br> Email id :
                          <c:out value="${param.email}"></c:out>
</body>
</html>

<c:exception> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>

<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<!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>Welcome Page</title>
</head>
<body>
          <c:catch var="catchException">
            <%
                   int x = 5 / 0;
            %>
</c:catch>
           <c:if test="${catchException != null}">
        <p>
            The exception is : ${catchException} <br /> There is an exception:
             ${catchException.message}
      </p>
        </c:if>
</body>
</html>

<c:redirect> Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!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>Index File</title>
</head>
<body>
         <c:redirect url="http://www.facebook.com/login.php? email=lakshman@gmail.com"/>
</body>
</html>
<sql> Tag Example
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
<!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>Index File</title>
</head>
<body>
      <sql:setDataSource var="dataSource"
          driver="oracle.jdbc.driver.OracleDriver"
          url="jdbc:oracle:thin:@localhost:1521:xe" user="lakshman"
          password="lakshman" scope="page" />
 
            <sql:query var="result" dataSource="${dataSource}"
             sql="select empno,ename,job,sal from emp"></sql:query>
      <c:forEach items="${result.columnNames }" var="col">
                 <c:out value="${col}"></c:out>
       </c:forEach>
<br>
<c:forEach items="${result.rows}" var="row">
         <c:out value="${row.empno}"></c:out>&nbsp;
         <c:out value="${row.ename}"></c:out>&nbsp;
         <c:out value="${row.job}"></c:out>&nbsp;
 
  <fmt:formatNumber value="${row.sal}" minIntegerDigits="4"
            minFractionDigits="2"></fmt:formatNumber>
<br>
</c:forEach>

</body>
</html>

Xml Documentation
If the XPath expression results in a boolean, <x:set> sets a java.lang.Boolean object; for a string, java.lang.String; and for a number, java.lang.Number.
book.xml
<?xml version="1.0" encoding="UTF-8"?>
<books>
      <book>
            <title>CoreJava</title>
             <author>Lakshman</author>
     </book>
<book>
          <title>AdvancedJava</title>
          <author>Harinath</author>
</book>
<book>
       <title>ServletAndJsp</title>
       <author>Rajesh</author>
</book>
<book>
        <title>Kubuntu</title>
        <author>Harinath</author>
</book>
</books>
index.jsp
<%@ taglib uri="http://java.sun.com/jsp/jstl/xml" prefix="x"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<html>
<head>
<title>Display Student Information</title>
<style>
table {
          border: 1px solid blue;
         width: 300px;
}
</style>
</head>
<body>
  <c:import var="xmlDoc" url="book.xml" />
            <x:parse var="parsedDocument" xml="${xmlDoc}" />
<table>
<tr><th>Title</th><th>Author</th></tr>
       
         <x:forEach select="$parsedDocument/books/book">
<tr>
 
             <td><x:out select="title" /></td>
             <td><x:out select="author" /></td>
</tr>
</x:forEach>
</table>
</body>
</html>
at

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