UploadServlet.java

package your.app;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

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;

import org.apache.tomcat.util.http.fileupload.servlet.ServletFileUpload;

/**
 * Servlet implementation class UploadServlet
 * 
 */
@WebServlet("/upload")
@MultipartConfig(maxFileSize = 1000000)
public class UploadServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	/**
	 * @see HttpServlet#HttpServlet()
	 */
	public UploadServlet() {
		super();
	}

	@Override
	protected void service(HttpServletRequest arg0, HttpServletResponse arg1)
			throws ServletException, IOException {
		super.service(arg0, arg1);
	}

	protected void doPut(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		File tempFile = null;
		InputStream input = null;

		if (ServletFileUpload.isMultipartContent(request)) {
			Part filePart = request.getPart("mydoc");
			String filename = getFilename(filePart);
			System.out.println("filename=" + filename);
			input = filePart.getInputStream();
			tempFile = new File(System.getProperty("java.io.tmpdir"), filename);
		} else {
			String fname = request.getParameter("fname");
			System.out.println("fname=" + fname);
			int p = fname.lastIndexOf('.');
			String ext = p != -1 ? fname.substring(p) : ".tmp";
			tempFile = File.createTempFile("upload", ext);
			input = request.getInputStream();
		}

		System.out.println("tempFile="+ tempFile);
		OutputStream output = new FileOutputStream(tempFile);
		try {
			byte[] buffer = new byte[1024];
			int length = 0;
			while ((length = input.read(buffer)) != -1) {
				output.write(buffer, 0, length);
			}
			output.flush();
		} finally {
			try {
				input.close();
			} catch (IOException ignored) {
			}
			try {
				output.close();
			} catch (IOException ignored) {
			}

		}

	}

	private static String getFilename(Part part) {
		for (String cd : part.getHeader("content-disposition").split(";")) {
			if (cd.trim().startsWith("filename")) {
				String filename = cd.substring(cd.indexOf('=') + 1).trim()
						.replace("\"", "");
				return filename.substring(filename.lastIndexOf('/') + 1)
						.substring(filename.lastIndexOf('\\') + 1); // MSIE fix.
			}
		}
		return null;
	}

}