This post is for beginners who want to use Apache commons fileupload to upload files. Maven is used for build and dependency management.
Note: I have specified the context root of the web application as cfp
We start with the index.jsp that provides the UI to upload the file.
<html>
<body>
<form name="fileform" action="/cfp/upload" method="POST" enctype="multipart/form-data">
<input type="file" name="resume" value="" width="50" />
<input type="submit" value="OK" />
</form>
</body>
</html>
The servlet that uses Commons fileupload and stores the files is as below.
package com.thea.servlet;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
/**
*
* @author karthikeyanc
*/
public class FileUploadServlet extends HttpServlet {
private static final int BYTE_READ_SIZE = 200000;
private static final String STORAGE_LOCATION = "E:\\d4444\\filestore\\";
private static final String TEMP_REPOSITORY = "E:\\d4444\\aas";
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException, FileUploadException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
try {
DiskFileItemFactory factory = new DiskFileItemFactory();
//Any file that is more than 5KB is stored in temporary repository. Feel free to change this value.
factory.setSizeThreshold(5000);
factory.setRepository(new File(TEMP_REPOSITORY));
ServletFileUpload upload = new ServletFileUpload(factory);
List<FileItem> items = upload.parseRequest(request);
for (FileItem item : items) {
if (!item.isFormField()) {
InputStream is = item.getInputStream();
FileOutputStream os = new FileOutputStream(new File(STORAGE_LOCATION + item.getName() ));
byte[] b = new byte[BYTE_READ_SIZE];
int bytesRead = 0;
while ((bytesRead = is.read(b)) != -1) {
os.write(b, 0, bytesRead);
}
os.flush();
os.close();
is.close();
}
}
out.println("<html>");
out.println("<head>");
out.println("<title>Servlet FileUploadServlet</title>");
out.println("</head>");
out.println("<body>");
out.println("<h1>File Uploaded</h1>");
out.println("</body>");
out.println("</html>");
} finally {
out.close();
}
}
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
try {
processRequest(request, response);
} catch (FileUploadException ex) {
Logger.getLogger(FileUploadServlet.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
Now the web.xml of the web application
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<display-name>FileUpload Web Application</display-name>
<servlet>
<servlet-name>FileUploadServlet</servlet-name>
<servlet-class>com.thea.servlet.FileUploadServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>FileUploadServlet</servlet-name>
<url-pattern>/upload</url-pattern>
</servlet-mapping>
</web-app>
And finally the pom.xml used by Maven to build the war file
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.thea</groupId>
<artifactId>fileupload</artifactId>
<packaging>war</packaging>
<version>0.1</version>
<name>fileupload Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>commons-fileupload</groupId>
<artifactId>commons-fileupload</artifactId>
<version>1.2.1</version>
</dependency>
<dependency>
<groupId>commons-io</groupId>
<artifactId>commons-io</artifactId>
<version>1.3.2</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>servlet-api</artifactId>
<version>6.0.16</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>el-api</artifactId>
<version>6.0.16</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>jsp-api</artifactId>
<version>6.0.16</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<finalName>fileupload</finalName>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.0.2</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
<properties>
<netbeans.hint.deploy.server>Tomcat60</netbeans.hint.deploy.server>
</properties>
</project>
![[This is a Roller site]](http://www.theasolutions.com/roller/karthik/resource/images/roller-logo.gif){kind=logo}