balance.java

用jsp＋servlet

package server;

import java.io.IOException;
import java.io.*;
import java.util.*;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class Balance 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 {
		doPost(request, response);
	}

	/**
	 * The doPost method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to
	 * post.
	 * 
	 * @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 doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		try {
			response.setContentType("application/x-java-serialized-object");

			// read a String-object from applet
			// instead of a String-object, you can transmit any object, which
			// is known to the servlet and to the applet
			InputStream in = request.getInputStream();
			ObjectInputStream inputFromApplet = new ObjectInputStream(in);
			String echo = (String) inputFromApplet.readObject();
			String aNumber = echo.split("&")[0];
			String pin = echo.split("&")[1];
			OutputStream outstr = response.getOutputStream();
			ObjectOutputStream oos = new ObjectOutputStream(outstr);
			DBConnection db = new DBConnection();
			db.executeQuery("select * from atm where accountnumber=" + aNumber
					+ " and pin=" + pin);
			String data = "";
			if (db.rs_next()) {
				data = db.rs_getDouble("balanceamount") + "";
			}
			oos.writeObject(data);
			oos.flush();
			oos.close();

		} catch (Exception e) {
			e.printStackTrace();
		}

	}

	/**
	 * The doPut method of the servlet. <br>
	 * 
	 * This method is called when a HTTP put request is received.
	 * 
	 * @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 doPut(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		// Put your code here
	}

}