highcharts实现从mysql数据库获取数据生成折线图

package zong; import java.io.IOException; import java.io.PrintWriter; import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.google.gson.Gson; @WebServlet("/HighCharts") public class HighCharts extends HttpServlet { /** * */ private static final long serialVersionUID = -5008685379832941710L; /** * Constructor of the object. */ public HighCharts() { super(); } /** * Destruction of the servlet. <br> */ public void destroy() { super.destroy(); // Just puts "destroy" string in log // Put your code here } /** * 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 { Connection conn = null; String sql; String url = "jdbc:mysql://localhost:3306/userdb"; String username = "root"; //数据库用户名 String password = "123456"; //数据库用户密码 try { Class.forName("com.mysql.jdbc.Driver"); conn = DriverManager.getConnection(url, username, password); Statement stmt = conn.createStatement(); sql = "select * from tem"; ResultSet rs = stmt.executeQuery(sql); List<Map<String, Object>> list = new ArrayList<Map<String, Object>>(); while (rs.next()) { System.out.println(rs.getString(1) + " " + rs.getString(2) + " " + rs.getString(3)+ " " + rs.getString(4)); Map<String, Object> map = new HashMap<String, Object>(); map.put("date", rs.getString(1)); map.put("temp", Double.parseDouble(rs.getString(3))); list.add(map); } Gson gson = new Gson(); String g = gson.toJson(list); PrintWriter out = response.getWriter(); out.println(g); out.flush(); out.close(); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException e) { e.printStackTrace(); } } /** * 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 { doGet(request, response); } /** * Initialization of the servlet. <br> * * @throws ServletException if an error occurs */ public void init() throws ServletException { // Put your code here } }