FLex调用servlet连接数据库.doc

FLex调用servlet连接数据库前言Flex 最重要的部分之一就是和服务器以及数据库的通讯。Flex 提供了三个类来与服务器通讯： HTTPService，RemoteObject 以及WebService。HTTPService 类提供了使用超文本传输协议（HTTP）与服务器通讯的方式。一个Flex 应用程序可以使用GET 或者POST 请求来发送数据到一个服务器并且处理这个请求返回的 XML 或者字符串。使用HTTPService 类，你可以与PHP 页面,ColdFusion 页面，JavaServe页面（ jsp），Java servlet， Ruby onRails， 以及ASP 动态网页通讯。与Java Servlet通讯由于本人是Java出身，所以这里就来讨论一下与Servlet的通讯方式。建立数据库这里选用MySql数据库，首先建立如下的数据库表写服务器端Java代码Servletview plaincopy to clipboardprint?package servlet; import java.io.IOException; import java.io.PrintWriter; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import PODO.Product; import db.ProductDao; public class GetProductServlet extends HttpServlet List result; /* * Constructor of the object. */ public GetProductServlet() super(); /* * Destruction of the servlet. */ public void destroy() super.destroy(); / Just puts destroy string in log / Put your code here /* * The doGet method of the servlet. * * 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 result = new ProductDao().getProduct(); String xmlContent = ; response.setContentType(text/xml;charset=utf-8); PrintWriter out = response.getWriter(); if (result != null) for (int i = 0; i result.size(); i+) Product p = (Product) result.get(i); xmlContent += + p.getName() + + p.getType() + + p.getPrice() + + p.getNum() + ; xmlContent += ; out.print(xmlContent); out.flush(); out.close(); /* * The doPost method of the servlet. * * 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 this.doGet(request, response); /* * Initialization of the servlet. * * throws ServletException * if an error occurs */ public void init() throws ServletException / Put your code here package servlet;import java.io.IOException;import java.io.PrintWriter;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import PODO.Product;import db.ProductDao;public class GetProductServlet extends HttpServlet List result;/* * Constructor of the object. */public GetProductServlet() super();/* * Destruction of the servlet. */public void destroy() super.destroy(); / Just puts destroy string in log/ Put your code here/* * The doGet method of the servlet. * * 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 result = new ProductDao().getProduct();String xmlContent = ;response.setContentType(text/xml;charset=utf-8);PrintWriter out = response.getWriter();if (result != null) for (int i = 0; i result.size(); i+) Product p = (Product) result.get(i);xmlContent += + p.getName() + + p.getType() + + p.getPrice()+ + p.getNum() + ;xmlContent += ;out.print(xmlContent);out.flush();out.close();/* * The doPost method of the servlet. * * 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 this.doGet(request, response);/* * Initialization of the servlet. * * throws ServletException * if an error occurs */public void init() throws ServletException / Put your code here 数据库连接view plaincopy to clipboardprint?public class MyConnection public Connection conn = null; public MyConnection() try / 注册数据库驱动程序为MYSQL驱动 Class.forName(com.mysql.jdbc.Driver); catch (java.lang.ClassNotFoundException e) System.err.println(mydb(): + e.getMessage(); try conn = DriverManager.getConnection( jdbc:mysql:/:3306/flex, root, root); catch (SQLException ex) System.err.println(conn: + ex.getMessage(); public Connection getDbConnection() return conn; public class MyConnection public Connection conn = null;public MyConnection() try / 注册数据库驱动程序为MYSQL驱动Class.forName(com.mysql.jdbc.Driver); catch (java.lang.ClassNotFoundException e) System.err.println(mydb(): + e.getMessage();try conn = DriverManager.getConnection(jdbc:mysql:/:3306/flex,root, root); catch (SQLException ex) System.err.println(conn: + ex.getMessage();public Connection getDbConnection() return conn; DAOview plaincopy to clipboardprint?public class ProductDao Connection conn; ResultSet rs; Statement stmt; public ProductDao() conn = new MyConnection().getDbConnection(); try stmt = conn.createStatement(); catch (SQLException e) / TODO Auto-generated catch block e.printStackTrace(); public List getProduct() List list = new ArrayList(); try String sql = select * from product; rs = stmt.executeQuery(sql); while (rs.next() String name=rs.getString(name); String type=rs.getString(type); double price=Double.parseDouble(rs.getString(price); int num=Integer.parseInt(rs.getString(num); Product p=new Product(name,type,price,num); list.add(p); rs.close(); stmt.close(); conn.close(); catch (SQLException e) / TODO Auto-generated catch block e.printStackTrace(); finally return list; public class ProductDao Connection conn;ResultSet rs;Statement stmt;public ProductDao() conn = new MyConnection().getDbConnection();try stmt = conn.createStatement(); catch (SQLException e) / TODO Auto-generated catch blocke.printStackTrace();public List getProduct() List list = new ArrayList();try String sql = select * from product;rs = stmt.executeQuery(sql);while (rs.next() String name=rs.getString(name);String type=rs.getString(type);double price=Double.parseDouble(rs.getString(price);int num=Integer.parseInt(rs.getString(num);Product p=new Product(name,type,price,num);list.add(p); rs.close(); stmt.close(); conn.close(); catch (SQLException e) / TODO Auto-generated catch blocke.printStackTrace(); finally return list; PODOview plaincopy to clipboardprint?public class Product private String name; private String type; private double price; private int num; public Product(String name, String type, double price, int num) = name; this.type = type; this.price = price; this.num = num; public String getName() return name; public void setName(String name) = name; public String getType() return type; public void setType(String type) this.type = type; public double getPrice() return price; public void setPrice(double price) this.price = price; public int getNum() return num; public void setNum(int num) this.num = num; public class Product private String name;private String type;private double price;private int num;public Product(String name, String type, double price, int num) = name;this.type = type;this.price = price;this.num = num;public String getName() return name;public void setName(String name) = name;public String getType() return type;public void setType(String type) this.type = type;public double getPrice() return price;public void setPrice(double price) this.price = price;public int getNum() return num;public void setNum(int num) this.num = num; 部署TOMCAT这一部分略过，如果觉得手动部署比较麻烦，我们可以使用MyEclipse插件。值得注意的是web.xml文件的配置，一定