filedownload.java

OBPM是一个开源

package cn.myapps.base.action.filedownload;

import java.io.IOException;
import java.io.OutputStream;

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

import cn.myapps.base.action.BlobFileObject;
import cn.myapps.constans.Web;

public class FileDownload extends HttpServlet {

	static final private String CONTENT_TYPE = "application/octet-stream; charset=GBK";

	/* (non-Javadoc)
	 * @see javax.servlet.GenericServlet#init()
	 */
	public void init() throws ServletException {
	}

	/* (non-Javadoc)
	 * @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doProcess(request, response);
	}

	/* (non-Javadoc)
	 * @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doProcess(request, response);
	}

	/**
	 * File upload process.
	 * @param request The http process.
	 * @param response The http response.
	 * @throws ServletException
	 * @throws IOException
	 */
	public void doProcess(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		OutputStream os = null;
		try {
			BlobFileObject bfo = (BlobFileObject) request
					.getAttribute(Web.DOWNLOAD_BLOB_FILE_OBJECT);
			String fileName = bfo.getFilename();
			String fileType = bfo.getContentType();
			byte[] fileContent = (byte[]) bfo.getContent();

			response.reset();
			response.resetBuffer();
			String charset = response.getCharacterEncoding();

			byte[] temp = fileName.getBytes("gb2312");
			fileName = new String(temp, charset);

			//System.out.println("response.getCharacterEncoding()->"
			//		+ response.getCharacterEncoding());
			//System.out.println("Locale.getDefault()->" + Locale.getDefault());

			response.addHeader("Content-Disposition", "attachment; filename="
					+ fileName);

			//	System.out.println("fileType->"+fileType);
			response.setContentType(fileType);
			int len = fileContent.length;
			response.setContentLength(len);
			
			os = response.getOutputStream();
			os.write(fileContent, 0, len);
		} catch (Exception ex) {
			throw new ServletException(ex);
		} finally {
			os.close();
		}
	}
}