VaadinJasperPrintServlet.java

/*
 * VaadinJasperPrintServlet.java
 * Designed to print a JasperReport report by name to the requested
 * output sink.
 * The default output sink is HTML.
 *
 *
 *
 * Created on 12 July 2002, 13:54
 */

package au.com.vaadinutils.jasper.servlet;

import java.util.Map;

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

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

/**
 * @author bsutton
 * @version
 */
public class VaadinJasperPrintServlet extends HttpServlet
{

    public static final String IMAGES_MAP = "IMAGES_MAP";
    private static final long serialVersionUID = -4735461255420730963L;
    static Logger logger = LogManager.getLogger();

    /**
     * Called to show an image that has been loaded into the session be a prior
     * call to doPrint.
     */
    @Override
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    {
        @SuppressWarnings("unchecked")
        Map<String, byte[]> imagesMap = (Map<String, byte[]>) request.getSession().getAttribute(IMAGES_MAP);

        try
        {
            if (imagesMap != null)
            {
                String imageName = request.getParameter("image");
                if (imageName != null)
                {
                    byte[] imageData = imagesMap.get(imageName);

                    if (imageData == null)
                        throw new IllegalStateException(
                                "The passed image (" + imageName + " has not been loaded into the session.");

                    response.setContentLength(imageData.length);
                    try (ServletOutputStream out = response.getOutputStream();)
                    {
                        out.write(imageData, 0, imageData.length);
                        out.flush();
                    }
                }
            }
        }
        catch (Exception e)
        {
            logger.error(e, e);
        }
    }

}