{"id":194,"date":"2007-09-06T00:00:00","date_gmt":"2007-09-06T00:00:00","guid":{"rendered":"http:\/\/www.strongd.net\/?p=194"},"modified":"2007-09-06T00:00:00","modified_gmt":"2007-09-06T00:00:00","slug":"Logic Equal Tag (...<\/logic:equal>)","status":"publish","type":"post","link":"https:\/\/www.strongd.net\/?p=194","title":{"rendered":"Logic Equal Tag (…<\/logic:equal>)"},"content":{"rendered":"


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equal tag –<\/FONT> if the requested variable is equal to the specified value then this tag is used to evaluate the contents contained in the nested body parts of this tag.<\/I><\/FONT><\/H3>
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Compares the variable passed against the specified constant value. The nested body content of this tag is evaluated if the variable and value are equal<\/STRONG>.<\/FONT><\/P>
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Attribute Name<\/FONT><\/TH>
\n		Description<\/FONT><\/TH><\/TR><\/THEAD>
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cookie<\/B><\/FONT><\/TD>
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The variable contains  the cookie value needed to compare .Here the name is specified by this attribute.<\/FONT><\/P><\/TD><\/TR>
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header<\/B><\/FONT><\/TD>
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The variable contains the header value needed to compare whose name is specified by this attribute. The name match is performed in a case insensitive manner.<\/FONT><\/P><\/TD><\/TR>
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name<\/B><\/FONT><\/TD>
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The variable to be compared is the JSP bean specified by this attribute, if property<\/CODE> is not specified, or the value of the specified property of this bean, if property<\/CODE> is specified.<\/FONT><\/P><\/TD><\/TR>
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parameter<\/B><\/FONT><\/TD>
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The variable to be compared is the first, or only, value of the request parameter specified by this attribute.<\/FONT><\/P><\/TD><\/TR>
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property<\/B><\/FONT><\/TD>
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The variable contains  the bean property value needed to compare ,it is specified by this attribute. The property reference can be simple, nested, and\/or indexed.<\/FONT><\/P><\/TD><\/TR>
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scope<\/B><\/FONT><\/TD>
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This specifies the bean scope within which  the bean is searched  by the name<\/CODE> property, or “any scope” if not specified.<\/FONT><\/P><\/TD><\/TR>
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value<\/B><\/FONT><\/TD>
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The constant value is specified by other attribute(s) of this tag, needed to compare<\/FONT><\/P><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Logic notEqual Tag (<logic:notEqual >…<\/logic:notEqual>) <\/FONT><\/H1>
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notEmpty<\/FONT><\/STRONG> – if the requested variable is not equal to the specified value <\/I><\/FONT>then this tag is used to evaluate the contents contained in the nested body parts of this tag.<\/I><\/FONT>
<\/I><\/FONT><\/H3>
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Compares the variable passed against the specified constant value. The nested body content of this tag is evaluated if the variable and value are not equal<\/STRONG>.<\/FONT>

Attributes of notEmpty Tag<\/B><\/FONT><\/P>
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Attribute Name<\/FONT><\/TH>
\n		Description<\/FONT><\/TH><\/TR><\/THEAD>
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cookie<\/B><\/FONT><\/TD>
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The variable contains  the cookie value needed to compare .Here the name is specified by this attribute.<\/FONT><\/P><\/TD><\/TR>
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header<\/B><\/FONT><\/TD>
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The variable contains the header value needed to compare whose name is specified by this attribute. The name match is performed in a case insensitive manner.<\/FONT><\/P><\/TD><\/TR>
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name<\/B><\/FONT><\/TD>
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The variable to be compared is the JSP bean specified by this attribute, if property<\/CODE> is not specified, or the value of the specified property of this bean, if property<\/CODE> is specified.<\/FONT><\/P><\/TD><\/TR>
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parameter<\/B><\/FONT><\/TD>
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The variable to be compared is the first, or only, value of the request parameter specified by this attribute.<\/FONT><\/P><\/TD><\/TR>
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property<\/B><\/FONT><\/TD>
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The variable contains  the bean property value needed to compare ,it is specified by this attribute. The property reference can be simple, nested, and\/or indexed.<\/FONT><\/P><\/TD><\/TR>
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scope<\/B><\/FONT><\/TD>
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This specifies the bean scope within which  the bean is searched  by the name<\/CODE> property, or “any scope” if not specified.<\/FONT><\/P><\/TD><\/TR>
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value<\/B><\/FONT><\/TD>
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The constant value is specified by other attribute(s) of this tag, needed to compare<\/FONT><\/P><\/TD><\/TR><\/TBODY><\/TABLE>
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Example Illustrating the use of the Equal<logic:equal> and the notEqual <logic:notEqual> logic tags.<\/FONT><\/H2>
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Here you will learn to use the Struts  Logic  Equal and notEqual tags. We will cover an example that will show  a comparison between  the two logic tags (ie..<logic:equal > and the <logic:notEqual >).<\/FONT><\/P>
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Example code<\/B><\/FONT><\/P>
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Creating an <\/FONT><\/B>Action  Class<\/B><\/FONT><\/P>
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Develop a simple action class <\/FONT>LogicAction.java.<\/FONT><\/CODE><\/P>
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package<\/FONT> <\/FONT><\/B>roseindia.net;

import <\/B>java.io.*;
import <\/B>java.util.*;

\/**<\/FONT><\/CODE>
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* @author Amit Gupta
* @Web http:\/\/www.roseindia.net
* @Email struts@roseindia.net

<\/A>**\/
import <\/B>javax.servlet.http.HttpServletRequest;
import <\/B>javax.servlet.http.HttpServletResponse;
import <\/B>javax.servlet.ServletException;
import <\/B>org.apache.struts.action.*;

public class <\/B>LogicAction extends <\/B>Action 
{
  public <\/B>ActionForward execute(ActionMapping mapping,
    ActionForm form,
    HttpServletRequest request,
    HttpServletResponse response)
    throws <\/B>IOException, ServletException {

      

        return <\/B>mapping.findForward(“success”);
    }
}<\/FONT><\/CODE> <\/P><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Creating Form Bean<\/FONT><\/B><\/P>
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Our form bean class contains only one property number<\/B>. Here is the code of FormBean <\/FONT>(<\/FONT>Logic<\/FONT><\/CODE>Form<\/CODE>.java)<\/FONT><\/P>
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package <\/B>roseindia.net;

import <\/B>org.apache.struts.action.*;

\/**

* @author Amit Gupta
* @Web http:\/\/www.roseindia.net
* @Email struts@roseindia.net
<\/A>
**\/
<\/FONT><\/CODE>
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import <\/B>javax.servlet.http.HttpServletRequest;
import <\/B>javax.servlet.http.HttpServletResponse;

public class <\/B>LogicForm extends <\/B>ActionForm 
{
    
    private <\/B>long number;        
  public <\/B>long getNumber() 
    {
        return <\/B>number;
    }
    
    public void <\/B>setNumber(long number) 
    {
    this<\/B>.number=number;
  }
   
    
  
    
}<\/FONT><\/CODE> <\/P><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Defining form Bean in struts-config.xml file<\/FONT><\/B><\/P>
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Add the following entry in the struts-config.xml file for defining the form bean<\/FONT><\/P>
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<form-bean name=”LogicForm<\/CODE>”  type=”roseindia.net.LogicForm<\/CODE>” \/><\/FONT><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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 Developing the Action Mapping in the struts-config.xml
<\/FONT><\/B>
Here, Action mapping helps to select the method from the Action class for specific requests.<\/FONT><\/P>
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<action path=”\/LogicAction”
type=”roseindia.net.LogicAction”
name=”LogicForm”
scope=”request”
input=”\/pages\/InputLogic.jsp”>
<forward name=”success” path=”\/pages\/output.jsp”\/>
<\/action><\/FONT><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Developing the<\/FONT> <\/FONT>InputLogic.jsp page<\/FONT><\/P>
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<%@ taglib uri=”\/tags\/struts-html” prefix=”html” %>
<%@ taglib uri=”\/tags\/struts-logic” prefix=”logic” %>

<html:html>
<head>
<title>Using &lt;logic&gt; Tags<\/title>
<\/head>

<body>
<h1>Using &lt;logic&gt; Tags<\/h1>

<html:form action=”\/LogicAction” method =”post”>

<h2>Enter a number:<\/h2>
<html:text property=”number”\/>

<br>
<h3>The &lt;logic:Equal&gt;tag works if you enter 1<\/h3>

<h3>else The &lt;logic:notEqual&gt; is processed <\/h3>

<br>

<html:submit value=”Submit”\/>


<html:cancel\/>
<\/html:form>
<\/body>
<\/html:html>
<\/FONT><\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Developing the <\/FONT>output.jsp <\/FONT>page<\/FONT><\/P>
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<%@ taglib uri=”\/tags\/struts-bean” prefix=”bean” %>
<%@ taglib uri=”\/tags\/struts-logic” prefix=”logic” %>

<HTML>
<HEAD>
<TITLE>Here’s Your Data…<\/TITLE>
<\/HEAD>

<BODY>
<H3>Here’s Your Data…<\/H3>

<h4>The number entered is:

<bean:write name=”LogicForm” property=”number”\/><\/h4>

<\/FONT><logic:equal<\/B> name=”LogicForm” property=”number” value=”1″>
<h4>Using the tag &lt;logic:equal &gt;<\/h4> 
Result : Equal
<\/logic:equal<\/B>>

<logic:notEqual<\/B> name=”LogicForm” property=”number” value=”1″>
<h4>Using the tag &lt;logic:notEqual &gt; <\/h4> 
Result : notEqual
<\/logic:notEqual<\/B>>
<\/FONT>

<\/BODY>
<\/HTML><\/FONT> <\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Add the following line in the index.jsp to call the form.<\/FONT><\/P>
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<li>
<html:link page=”\/pages\/InputLogic.jsp”>Struts File Upload<\/html:link>
<br>
Example demonstrates  how LogicAction Class works.
<\/li>
<\/FONT><\/P>
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Building and Testing the Example <\/FONT><\/B><\/P>
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To build and deploy the application go to Struts\\Strutstutorial directory and type ant on the command prompt. This will deploy the application. Open the browser and navigate to the <\/FONT>InputLogic.jsp <\/B>page. Your browser displays the following  page.<\/FONT><\/P>
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Writing value equal to1 to the <\/FONT>InputLogic<\/B>.jsp <\/B>page displays the working of  the  Equal Logic tag <logic:equal > <\/B><\/FONT><\/P>
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<\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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It displays the following out.jsp <\/B>page<\/FONT><\/P>
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<\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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Now  write any data other than 1 to the <\/FONT>InputLogic.jsp to see the working of  the notEqual logic tag <logic:notEqual><\/B><\/FONT><\/P>
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<\/TD><\/TR><\/TBODY><\/TABLE><\/DIV>
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The<\/FONT> <logic:notEqual > evaluated here displays the <\/FONT>output.jsp<\/FONT> as<\/FONT><\/P>
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<\/TD><\/TR><\/TBODY><\/TABLE><\/DIV><\/DIV><\/p>\n","protected":false},"excerpt":{"rendered":"

equal tag – if the requested variable is equal to the specified value then this tag is used to evaluate the contents contained in the nested body parts of this tag. Compares the variable passed against the specified constant value. The nested body content of this tag is evaluated if the variable and value are equal. … Continue reading Logic Equal Tag (…<\/logic:equal>)<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-194","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"https:\/\/www.strongd.net\/index.php?rest_route=\/wp\/v2\/posts\/194","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.strongd.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.strongd.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.strongd.net\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.strongd.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=194"}],"version-history":[{"count":0,"href":"https:\/\/www.strongd.net\/index.php?rest_route=\/wp\/v2\/posts\/194\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.strongd.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=194"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.strongd.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=194"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.strongd.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=194"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}