UrlServlet.java Source code

Introduction

Here is the source code for UrlServlet.java

Source

import java.io.BufferedInputStream;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;

import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class UrlServlet extends HttpServlet {

    public void doGet(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        //get the 'file' parameter
        String fileName = (String) request.getParameter("file");
        if (fileName == null || fileName.equals(""))
            throw new ServletException("Invalid or non-existent file parameter in UrlServlet servlet.");

        if (fileName.indexOf(".pdf") == -1)
            fileName = fileName + ".pdf";

        URL pdfDir = null;
        URLConnection urlConn = null;
        ServletOutputStream stream = null;
        BufferedInputStream buf = null;
        try {

            pdfDir = new URL(getServletContext().getInitParameter("remote-pdf-dir") + fileName);

        } catch (MalformedURLException mue) {

            throw new ServletException(mue.getMessage());
        }
        try {

            stream = response.getOutputStream();

            //set response headers
            response.setContentType("application/pdf");
            response.addHeader("Content-Disposition", "attachment; filename=" + fileName);

            urlConn = pdfDir.openConnection();
            response.setContentLength((int) urlConn.getContentLength());

            buf = new BufferedInputStream(urlConn.getInputStream());
            int readBytes = 0;

            //read from the file; write to the ServletOutputStream
            while ((readBytes = buf.read()) != -1)
                stream.write(readBytes);
        } catch (IOException ioe) {
            throw new ServletException(ioe.getMessage());
        } finally {
            if (stream != null)
                stream.close();
            if (buf != null)
                buf.close();
        }
    }

    public void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        doGet(request, response);
    }
}