watchservlet.java

基本完成上传本地图片和信息的分类显示

package com.servlet;

import java.io.IOException;

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

import com.bean.Student;
import com.bean.StudentAccess;

/**
 * Servlet implementation class for Servlet: WatchServlet
 * 
 */
public class WatchServlet extends javax.servlet.http.HttpServlet implements
		javax.servlet.Servlet {
	static final long serialVersionUID = 1L;

	/*
	 * (non-Java-doc)
	 * 
	 * @see javax.servlet.http.HttpServlet#HttpServlet()
	 */
	public WatchServlet() {
		super();
	}

	/*
	 * (non-Java-doc)
	 * 
	 * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request,
	 *      HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(request, response);
	}

	/*
	 * (non-Java-doc)
	 * 
	 * @see javax.servlet.http.HttpServlet#doPost(HttpServletRequest request,
	 *      HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		StudentAccess dao = new StudentAccess();
		String no = (String) request.getParameter("id");
		int id = Integer.parseInt(no);
		String action = request.getParameter("action");

		if (action.equals("2")) {
			dao.delStudent(id);
			RequestDispatcher rd = getServletConfig().getServletContext()
					.getRequestDispatcher("/show");
			rd.forward(request, response);
		} else {
			Student bn = dao.getStudent(id);
			if (action.equals("1")) {
				request.setAttribute("bean", bn);
				RequestDispatcher rd = request.getRequestDispatcher("show.jsp");
				rd.forward(request, response);
			} else if (action.equals("3")) {
				request.setAttribute("bean", bn);
				RequestDispatcher rd = request.getRequestDispatcher("edit.jsp");
				rd.forward(request, response);
			} else if (action.equals("4")) {
				showMyPhoto(bn.getBytes(), response);
			}
		}
	}

	public void showMyPhoto(byte[] ab, HttpServletResponse response) {

		try {
			response.setContentType("image/jpg");
			response.reset();
			ServletOutputStream op = response.getOutputStream();
			op.write(ab);
			op.flush();
			op.close();
		} catch (NullPointerException e) {
			e.printStackTrace();
		} catch (Exception ex) {
			ex.printStackTrace();
		}
	}

}