package servlet;

import java.io.IOException;

import java.io.PrintWriter;

import java.io.Writer;

import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import java.sql.*;

import db.Db;

public class ServletTest extends HttpServlet{

protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

resp.setContentType("text/html;charset=utf-8");

/* 设置响应头允许ajax跨域访问 */

resp.setHeader("Access-Control-Allow-Origin", "*");

/* 星号表示所有的异域请求都可以接受， */

resp.setHeader("Access-Control-Allow-Methods", "GET,POST");

PrintWriter printWriter = resp.getWriter();

printWriter.flush();

//从数据库取值

Connection connection = Db.getConnection();

String sql = "select * from math";

try {

Statement statement = connection.createStatement();

ResultSet resultSet = statement.executeQuery(sql);

printWriter.println("[");

while (resultSet.next()) {

System.out.print(resultSet.getObject(2));

if (!resultSet.isLast()) {

System.out.println(",");

}

printWriter.print(resultSet.getObject(2));

if (!resultSet.isLast()) {

printWriter.println(",");

}

}

printWriter.println("]");

printWriter.flush();

} catch (SQLException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

}

protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

// TODO Auto-generated method stub

this.doPost(req, resp);

}

}