utilities.UpoadFile.java Source code

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Here is the source code for utilities.UpoadFile.java

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package utilities;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Iterator;
import java.util.List;

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.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

/**
 *
 * @author Tuan Anh
 */
public class UpoadFile extends HttpServlet {

    private static final long serialVersionUID = 1L;

    private static final String UPLOAD_DIRECTORY = "upload/images";
    private static final int THRESHOLD_SIZE = 1024 * 1024 * 3; // 3MB
    private static final int MAX_FILE_SIZE = 1024 * 1024 * 40; // 40MB
    private static final int MAX_REQUEST_SIZE = 1024 * 1024 * 50; // 50MB

    /**
     * handles file upload via HTTP POST method
     * @param request
     * @param response
     * @throws javax.servlet.ServletException
     * @throws java.io.IOException
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        // checks if the request actually contains upload file
        if (!ServletFileUpload.isMultipartContent(request)) {
            PrintWriter writer = response.getWriter();
            writer.println("Request does not contain upload data");
            writer.flush();
            return;
        }

        // configures upload settings
        DiskFileItemFactory factory = new DiskFileItemFactory();
        factory.setSizeThreshold(THRESHOLD_SIZE);
        factory.setRepository(new File(System.getProperty("java.io.tmpdir")));

        ServletFileUpload upload = new ServletFileUpload(factory);
        upload.setFileSizeMax(MAX_FILE_SIZE);
        upload.setSizeMax(MAX_REQUEST_SIZE);

        // constructs the directory path to store upload file
        String uploadPath = getServletContext().getRealPath("") + File.separator + UPLOAD_DIRECTORY;
        // creates the directory if it does not exist
        File uploadDir = new File(uploadPath);
        if (!uploadDir.exists()) {
            uploadDir.mkdir();
        }

        try {
            // parses the request's content to extract file data
            List formItems = upload.parseRequest(request);
            Iterator iter = formItems.iterator();

            // iterates over form's fields
            while (iter.hasNext()) {
                FileItem item = (FileItem) iter.next();
                // processes only fields that are not form fields
                if (!item.isFormField()) {
                    String fileName = new File(item.getName()).getName();
                    String filePath = uploadPath + File.separator + fileName;
                    File storeFile = new File(filePath);

                    // saves the file on disk
                    item.write(storeFile);
                }
            }
            request.setAttribute("message", "Upload has been done successfully!");
        } catch (Exception ex) {
            request.setAttribute("message", "There was an error: " + ex.getMessage());
        }
    }
}