Struts2 File Upload Example

The fileUpload interceptor automatically works for all the requests that includes files.

We can use this interceptor to control the working of file upload in struts2 such as defining allowed types, maximum file size etc.

Parameters of fileupload interceptor

There are 2 parameters defined for fileupload interceptor.

Parameter	Description
maximumSize	specifies maximum size of the file to be uploaded.
allowedTypes	specifies allowed types. It may be image/png, image/jpg etc.

It automatically adds 3 parameters in the request:

File file represents the file. We can apply methods on this object.
String fileName represents the filename of the file.
String contentType specifies the content type of the file.

Image upload example using struts 2

Let's see the directory structure of file upload application.

file upload in struts 2 directory structure

1) Create UserImage.jsp

This jsp page creates a form using struts UI tags. It receives name, password and email id from the user.

index.jsp

<%@ page contentType="text/html; charset=UTF-8"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<html>
	<head>
		<title>Upload User Image</title>
	</head>
	<body>
		<h2>
			Struts2 File Upload & Save Example without Database
		</h2>
		<s:actionerror />
		<s:form action="userImage" method="post" enctype="multipart/form-data">
			<s:file name="userImage" label="Image" />
			<s:submit value="Upload" align="center" />
		</s:form>
	</body>
</html>

2) Create SuccessUserImage.jsp

This jsp page creates a form using struts UI tags. It receives name, password and email id from the user.

SuccessUserImage.jsp

<%@ page contentType="text/html; charset=UTF-8"%><%@ taglib prefix="s"
	uri="/struts-tags"%>
<html>
	<head>
		<title>Success: Upload User Image</title>
	</head>
	<body>
		<h2>
			Struts2 File Upload Example
		</h2>
		User Image:	<s:property value="userImage" /><br/>
		Content Type:<s:property value="userImageContentType" /><br/>
		File Name:	<s:property value="userImageFileName" /><br/>
		Uploaded Image:	<img src="userimages/<s:property value="userImageFileName"/>" 
                                                     width="100" height="100" />
	</body>
</html>

3) Create the action class

This action class inherits the ActionSupport class and overrides the execute method.

RegisterAction.java

package com.trainingtrains;
import java.io.File;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.io.FileUtils;
import org.apache.struts2.interceptor.ServletRequestAware;
import com.opensymphony.xwork2.ActionSupport;

public class FileUploadAction extends ActionSupport implements
		ServletRequestAware {
	private File userImage;
	private String userImageContentType;
	private String userImageFileName;

	private HttpServletRequest servletRequest;
	public String execute() {
		try {
String filePath = servletRequest.getSession().getServletContext().getRealPath("/").concat("userimages");
			
		System.out.println("Image Location:" + filePath);//see the server console for actual location
		File fileToCreate = new File(filePath, this.userImageFileName);
		FileUtils.copyFile(this.userImage, fileToCreate);//copying image in the new file
			
		return SUCCESS;
	}
	public File getUserImage() {
		return userImage;
	}
	public void setUserImage(File userImage) {
		this.userImage = userImage;
	}
	public String getUserImageContentType() {
		return userImageContentType;
	}

	public void setUserImageContentType(String userImageContentType) {
		this.userImageContentType = userImageContentType;
	}
	public String getUserImageFileName() {
		return userImageFileName;
	}
	public void setUserImageFileName(String userImageFileName) {
		this.userImageFileName = userImageFileName;
	}
	public void setServletRequest(HttpServletRequest servletRequest) {
		this.servletRequest = servletRequest;

	}
}

4) Create struts.xml

This xml file defines an extra result by the name input, and an interceptor jsonValidatorWorkflowStack.

struts.xml

    
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">


<struts>
	<package name="fileUploadPackage" extends="struts-default">
		<action name="userImage" class="com.trainingtrains.FileUploadAction">
			<interceptor-ref name="fileUpload">
				<param name="maximumSize">2097152</param>

				<param name="allowedTypes">
					image/png,image/gif,image/jpeg,image/pjpeg
                                </param>
			</interceptor-ref>
			<interceptor-ref name="defaultStack"></interceptor-ref>
			<result name="success">SuccessUserImage.jsp</result>
			<result name="input">UserImage.jsp</result>
		</action>
	</package>
</struts>

download this example developed in eclipse ide (without jar)