Struts <logic:equal> and <logic:notEqual> Tag

The <logic:equal> tag evaluates if the requested variable is equal to specific value. Whereas <logic:notEqual> tag evaluates if the requested variable is not equal to specific value. In order to use the Struts HTML Tags you need to include the following taglib directive in the jsp page.

<%@taglib uri="/WEB-INF/struts-html.tld" prefix="html" %> 

First create a new Dynamic Web Project and configure it as Maven Project. For Reference, Click Here

Add the following dependencies in pom.xml


1. Create DynaActionForm

First we create an entry for DynaActionForm in struts-config.xml

    <form-bean name="EmployeeForm"  
        <form-property name="employeeId" type="java.lang.Integer" />
         <form-property name="employeeName" type="java.lang.String" />
         <form-property name="employeeList" type="java.util.ArrayList" />

2. Action Class (Controller)

Let us create an Action class that will handle the request. Here Action Class contains the business logic.

package com.kruders.action;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.DynaActionForm;
public class EmployeeAction extends Action{
    public ActionForward execute(ActionMapping mapping,ActionForm form,
        HttpServletRequest request, HttpServletResponse response)
                throws Exception {
        DynaActionForm EmployeeForm = (DynaActionForm)form;
        EmployeeForm.set("employeeName","Tajinder Singh");
        return mapping.findForward("success");

3. View

Create welcome.jsp and write the following code.

<%@taglib uri="" prefix="html"%>
<title>Welcome Page</title>
<html:form action="/checkEqual">
    <html:submit>Click Here</html:submit> to check requested variable is equal to specific value or not</p>

Now create another jsp file checkEqual.jsp that contains the struts logic tag to to check the requested variable is equal to specific value or not.

<%@taglib uri="" prefix="html"%>
<%@taglib uri="" prefix="logic"%>
<%@taglib uri="" prefix="bean"%>
<title>Struts Logic Equal Tag <logic:equal> and Not Equal Tag <logic:notEqual></title>
<b>Struts - Check variable is equal to specific value or not using <logic:equal> and <logic:notEqual></b><br>
<logic:equal name="EmployeeForm" property="employeeName" value="Tajinder Singh">
Name : Tajinder Singh
<logic:notEqual name="EmployeeForm" property="employeeId" value="2">
<br>Employee Id is not equal to 2

4. Struts Config

Add the following code in struts-config.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts-config PUBLIC 
"-//Apache Software Foundation//DTD Struts Configuration 1.3//EN" 
        <form-bean name="EmployeeForm" 
            <form-property name="employeeId" type="java.lang.Integer" />
            <form-property name="employeeName" type="java.lang.String" />
        <forward name="checkEqual" path="/"/>
        <action input="/checkEqual.jsp" name="EmployeeForm" path="/checkEqual"  validate="true" scope="request" type="com.kruders.action.EmployeeAction">
            <forward name="success" path="/checkEqual.jsp" />

5. Deployment Descriptor

Now configure the deployment descriptor. Here, we have asked the container to give our ActionServlet any request that matches the pattern *.do

Add the following configuration information in the web.xml file


7. Run Project

Now when you run the project, following screen will be displayed as in Figure 33.1

Figure 33.1 Figure 33.1

Now when you click submit button on welcome page, following screen will be displayed as shown in Figure 33.2

Figure 33.2 Figure 33.2

The folder structure of the example is shown below in Figure 33.3

Figure 33.3 Figure 33.3

You can download the source code of this example here.

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