javax.servlet.http.Part class represents a part as uploaded to the server as part of a multipart/form-data request body. The part may represent either an uploaded file or form data. Here is one simple example to upload file using Servlet 3.0
index.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form method="post" action="/FileUploadServletExample/fileupload" enctype="multipart/form-data">
Choose file <input type="file" name="file">
<input type="submit" value="submit">
</form>
</body>
</html>
FileUploadServlet.java
package com.pretech;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.MultipartConfig;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.Part;
@MultipartConfig
@WebServlet("/fileupload")
public class FileUploadServlet extends HttpServlet {
private static final long serialVersionUID = -7205406034336084784L;
protected void doPost(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
Part filePart = request.getPart("file");
System.out.println("filename"+ filePart.getName());
String fileName = getFileName(filePart);
String fileLocation="c:/temp/";
InputStream inputStream = null;
OutputStream outputStream = null;
try {
File outputFilePath = new File(fileLocation + fileName);
inputStream = filePart.getInputStream();
outputStream = new FileOutputStream(outputFilePath);
int read = 0;
final byte[] bytes = new byte[1024];
while ((read = inputStream.read(bytes)) != -1) {
outputStream.write(bytes, 0, read);
}
} catch (FileNotFoundException fne) {
fne.printStackTrace();
} finally {
if (outputStream != null) {
outputStream.close();
}
if (inputStream != null) {
inputStream.close();
}
}
response.setContentType("text/html;UTF-8");
PrintWriter writer = response.getWriter();
writer.write("File upload completed");
writer.close();
}
private String getFileName(Part part) {
for (String content : part.getHeader("content-disposition").split(";")) {
if (content.trim().startsWith("filename")) {
return content.substring(content.indexOf('=') + 1).trim()
.replace("\"", "");
}
}
return null;
}
}
Output
