Struts 2 Redirect Action

In this section, you will get familiar with struts 2 Redirect action and learn to use it in the struts 2 application.

Redirect After Post: This post pattern is supported by Struts 2. This is a common pattern in web application. In which an action is redirected to another action. This is a common use to redirect action to display a page.

Redirect Action Result: This redirect pattern is supported by Struts 2. The ActionMapper provided by the ActionMapperFactory is used to redirect the browser to a URL that invokes the specified action. You can see a simple implementation of this in the following struts 2 application.

Redirects Dynamic Parameters: The action-redirect result takes following parameters:

actionName
namespace
method
encode
parse
location
prependServletContext

Follow the steps to develop a Redirect Action example:

Step 1: Create the struts.xml file and add the following xml snippet in the struts.xml file.


<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE struts PUBLIC

    "-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"

    "http://struts.apache.org/dtds/struts-2.0.dtd">



<struts>



    <!-- Rose India Struts 2 Tutorials -->

    <constant name="struts.enable.DynamicMethodInvocation" value="false" />

    <constant name="struts.devMode" value="true" />

<include file="struts-default.xml"/>

    <package name="roseindia" namespace="/roseindia" extends="struts-default">



        

    <!-- Redirect
    Action -->



     <action name="showAjaxLoginCancelForm">

      <result>/pages/ajaxloginCancel.jsp</result>

     </action>



    <action name="ajaxloginCancel" class="net.roseindia.Login">

      <result  name="input">/pages/ajaxloginCancel.jsp</result>

      <result  name="error">/pages/ajaxloginCancel.jsp</result>

      <result name="cancel" type="redirect">/pages/ajaxloginCancel.jsp</result>

      <result>/pages/ajaxloginsuccess.jsp</result>

    </action>

    

         <!-- Add actions here -->

    </package>





    <!-- Add packages here -->



</struts>

Step 2 : Create an input form.

ajaxloginCancel.jsp


<%@ taglib prefix="s" uri="/struts-tags"%>

<html>

  <head>

    <s:head theme="ajax" debug="true"/>

  </head>

  <body>

    <s:div id="loginDiv" theme="ajax">

    <div style="width: 300px;border-style: solid">

      <s:form action="ajaxloginCancel"  validate="true">

        <tr>

          <td colspan="2">

            Login

          </td>

        </tr>

        <tr>

          <td colspan="2">

            <s:actionerror />

            <s:fielderror />

          </td>  

          <s:textfield name="username" label="Login name"/>

          <s:password name="password" label="Password"/>

          <s:submit value="Submit" theme="ajax" targets="loginDiv" notifyTopics="/ajaxloginCancel"/>

          <s:submit action="showAjaxLoginCancelForm" value="Cancel" onclick="form.onsubmit=null"/>

          

      </s:form>

    </div>

    </s:div>

  </body>

</html>

Step 3 : Create an Action class.

Login.java


package net.roseindia;

import com.opensymphony.xwork2.ActionSupport;

import java.util.Date;





/**

 * <p> Validate a user login. </p>

 */

public class Login extends ActionSupport {





    public String execute() throws Exception {

    if(!getUsername().equals("Admin") || !getPassword().equals("Admin")){

            addActionError("Invalid user name or password! Please try again!");

            return ERROR;

    }

    if(getUsername().equals("Admin") || getPassword().equals("Admin")){

      return SUCCESS;

    }else{

      return NONE;

    }

  }





    // ---- Username property ----



    /**

     * <p>Field to store User username.</p>

     * <p/>

     */

    private String username = null;





    /**

     * <p>Provide User username.</p>

     *

     * @return Returns the User username.

     */

    public String getUsername() {

        return username;

    }



    /**

     * <p>Store new User username</p>

     *

     * @param value The username to set.

     */

    public void setUsername(String value) {

        username = value;

    }



    // ---- Username property ----



    /**

     * <p>Field to store User password.</p>

     * <p/>

     */

    private String password = null;





    /**

     * <p>Provide User password.</p>

     *

     * @return Returns the User password.

     */

    public String getPassword() {

        return password;

    }



    /**

     * <p>Store new User password</p>

     *

     * @param value The password to set.

     */

    public void setPassword(String value) {

        password = value;

    }



}

Step 4 : Create the appropriate validator as shown:

The validation.xml format is either <ActionClassName>-validation.xml or <ActionClassName>-<ActionAliasName>-validation.xml.

Login-validation.xml


<?xml version="1.0" encoding="UTF-8"?>

<!DOCTYPE validators PUBLIC 

      "-//OpenSymphony Group//XWork Validator 1.0.2//EN" 

      "http://www.opensymphony.com/xwork/xwork-validator-1.0.2.dtd">

      

<validators>

  <field name="username">

    <field-validator type="requiredstring">

      <param name="trim">true</param>

      <message>Login name is required</message>

    </field-validator>

  </field>

  <field name="password">

    <field-validator type="requiredstring">

      <param name="trim">true</param>

      <message>Password is required</message>

    </field-validator>

  </field>

</validators>

When entered the correct user name and password then the user gets the ajaxloginsuccess.jsp page displaying the entered text

ajaxloginsuccess.jsp


<html>

  <head>

    <title>Login Success</title>

  </head>

  <body>

    <p align="center"><font color="#000080" size="5">Login Successful !</font></p>

    <h1> Welcome to <%=request.getParameter("username")%>  </h1>

  </body>

</html>

Output:

When this application executes you get the following:

When you don't fill any field and click "Submit" button, you get:

If you click the "Cancel" button then redirect action executes and provides: