readcategoryphoto.java

基于struts+hibernate的电子商务网站。可运行。数据库mysql

package tarena.servlet;

import java.io.IOException;
import java.sql.Blob;
import java.sql.SQLException;

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

import tarena.dao.CategoryDAO;
import tarena.entity.Category;

/**
 * 读取分类图片
 * 2008-11-3
 * @author		达内科技[Tarena Training Group]
 * @version	1.0
 * @since		JDK1.6(建议) 
 */
@SuppressWarnings("serial")
public class ReadCategoryPhoto extends HttpServlet {

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		int categoryid=Integer.parseInt(request.getParameter("id"));
		
		response.setContentType("image/jpeg");
		ServletOutputStream out=response.getOutputStream();
		CategoryDAO dao = new CategoryDAO();
		Category c =  dao.findById(categoryid);
		Blob blob=c.getPhoto();
		if(blob==null){
			blob=dao.findById(1).getPhoto();
		}

		try {
			out.write(blob.getBytes(1, (int)blob.length()));
		} catch (SQLException e) {
			e.printStackTrace();
		}
	}

}