com.java2s.SendFilter.java Source code

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Here is the source code for com.java2s.SendFilter.java

Source

package com.java2s;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileInputStream;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;

public class SendFilter implements Filter {

    private final static String PDF_DIR = "d:\\book\\java2s";

    private final static String PDF_CONTENT_TYPE = "application/pdf";

    private FilterConfig config;

    /** Creates new SessionFilter */
    public SendFilter() {
    }

    public void init(FilterConfig filterConfig) throws ServletException {

        System.out.println("Instance created of " + getClass().getName());
        this.config = filterConfig;
    }

    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws java.io.IOException, ServletException {

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

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

        ServletOutputStream stream = null;
        BufferedInputStream buf = null;
        HttpServletResponse httpResp = null;
        try {

            httpResp = (HttpServletResponse) response;
            stream = httpResp.getOutputStream();
            File pdf = new File(PDF_DIR + "/" + fileName);

            //set response headers
            httpResp.setContentType(PDF_CONTENT_TYPE);
            httpResp.addHeader("Content-Disposition", "attachment; filename=" + fileName);
            httpResp.setContentLength((int) pdf.length());

            FileInputStream input = new FileInputStream(pdf);
            buf = new BufferedInputStream(input);
            int readBytes = 0;
            //read from the file; write to the ServletOutputStream
            while ((readBytes = buf.read()) != -1)
                stream.write(readBytes);

        } catch (Exception ioe) {

            //  throw new ServletException(ioe.getMessage());
            System.out.println(ioe.getMessage());

        } finally {

            if (buf != null)
                buf.close();
            if (stream != null) {
                stream.flush();
                //stream.close();
            }

        } //end finally
        chain.doFilter(request, httpResp);
    }

    public void destroy() {
        /*
         * called before the Filter instance is removed from service by the web
         * container
         */
    }
}