Anjaneya Tech: Struts File Upload Example

In this tutorial you will learn how to use Struts to write program to upload files. The interfaceorg.apache.struts.upload.FormFile is the heart of the struts file upload application. This interface represents a file that has been uploaded by a client. It is the only interface or class in upload package which is typically referenced directly by a Struts application.

Creating Form Bean

Our form bean class contains only one property theFile, which is of typeorg.apache.struts.upload.FormFile.

Here is the code of FormBean (StrutsUploadForm.java):

package roseindia.net;

import org.apache.struts.action.*;
import org.apache.struts.upload.FormFile;

/**
* @author Deepak Kumar
* @Web http://www.roseindia.net
* @Email roseindia_net@yahoo.com
*/

/**
* Form bean for Struts File Upload.
*
*/
public class StrutsUploadForm extends ActionForm
{
  private FormFile theFile;

  /**
* @return Returns the theFile.
*/
  public FormFile getTheFile() {
  return theFile;
  }
  /**
* @param theFile The FormFile to set.
*/
  public void setTheFile(FormFile theFile) {
  this.theFile = theFile;
  }
}

Creating Action Class

Our action class simply calls the getTheFile() function on the FormBean object to retrieve the reference of the uploaded file. Then the reference of the FormFile is used to get the uploaded file and its information. Here is the code of our action class(StrutsUploadAction.java):

package roseindia.net;

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.upload.FormFile;
/**
* @author Deepak Kumar
* @Web http://www.roseindia.net
* @Email roseindia_net@yahoo.com
*/

/**
* Struts File Upload Action Form.
*
*/
public class StrutsUploadAction extends Action
{
  public ActionForward execute(
  ActionMapping mapping,
  ActionForm form,
  HttpServletRequest request,
  HttpServletResponse response) throws Exception{
  StrutsUploadForm myForm = (StrutsUploadForm)form;

  // Process the FormFile
  FormFile myFile = myForm.getTheFile();
  String contentType = myFile.getContentType();
  String fileName  = myFile.getFileName();
  int fileSize = myFile.getFileSize();
  byte[] fileData  = myFile.getFileData();
  System.out.println("contentType: " + contentType);
  System.out.println("File Name: " + fileName);
  System.out.println("File Size: " + fileSize);

  return mapping.findForward("success");
  }
}

Defining form Bean in struts-config.xml file

Add the following entry in the struts-config.xml file for defining the form bean:

<form-bean
name="FileUpload"
type="roseindia.net.StrutsUploadForm"/>

Defining Action Mapping

Add the following action mapping entry in the struts-config.xml file:

Developing jsp page

Code of the jsp (FileUpload.jsp) file to upload is as follows:

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

<html:html locale="true">
<head>
<title>Struts File Upload Example</title>
<html:base/>
</head>
<body bgcolor="white">
<html:form action="/FileUpload" method="post" enctype="multipart/form-data">
<table>
<tr>
<td align="center" colspan="2">
<font size="4">Please Enter the Following Details</font>
</tr>

<tr>
<td align="left" colspan="2">
<font color="red"><html:errors/></font>
</tr>

<tr>
<td align="right">
File Name
</td>
<td align="left">
<html:file property="theFile"/>
</td>
</tr>

<tr>
<td align="center" colspan="2">
<html:submit>Upload File</html:submit>
</td>
</tr>
</table>

</html:form>
</body>
</html:html>

Note that we are setting the encrypt property of the form to enctype="multipart/form-data".

code for the success page (uploadsuccess.jsp) is:

<html>

<head>
<title>Success</title>
</head>

<body>

<p align="center"><font size="5" >File Successfully Received</font></p>

</body>

</html>

Add the following line in the index.jsp to call the form.

<li>
<html:link page="/pages/FileUpload.jsp">Struts File Upload</html:link>
<br>
Example shows you how to Upload File with Struts.
</li>

Building Example and Testing

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 FileUpload.jsp page. Your browser should display the file upload form:

Thanking You, I hope all goes well! Look forward to seeing more Java tutorials from me ( google+ ) in the future.

Anjaneya Tech

Friday, 17 May 2013

Struts File Upload Example

No comments:

Post a Comment

Simple CRUD in Laravel Framework