FLex调用servlet连接数据库

1、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

2、 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.

3、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

4、 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

5、 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, IOExcepti

6、on result = new ProductDao().getProduct(); String xmlContent = "<?xml version='1.0' encoding='utf-8'?><products>" response.setContentType("text/xml;charset=utf-8"); PrintWriter out = response.getWriter(); if (result != null) for (int i = 0; i < resu

7、lt.size(); i+) Product p = (Product) result.get(i); xmlContent += "<product><name>" + p.getName() + "</name><type>" + p.getType() + "</type><price>" + p.getPrice() + "</price><num>" + p.getNum() + "</num&

8、gt;</product>" xmlContent += "</products>" out.print(xmlContent); out.flush(); out.close(); /* * 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

9、 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

10、(request, response); /* * Initialization of the servlet. <br> * * 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.Ser

11、vletException;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 GetProductSe

12、rvlet() 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. * * par

13、am 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

14、ServletException, IOException result = new ProductDao().getProduct();String xmlContent = "<?xml version='1.0' encoding='utf-8'?><products>"response.setContentType("text/xml;charset=utf-8");PrintWriter out = response.getWriter();if (result != null) for

15、(int i = 0; i < result.size(); i+) Product p = (Product) result.get(i);xmlContent += "<product><name>" + p.getName() + "</name><type>"+ p.getType() + "</type><price>" + p.getPrice()+ "</price><num>" + p.getNum

16、() + "</num></product>"xmlContent += "</products>"out.print(xmlContent);out.flush();out.close();/* * 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 sen

17、d 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, IOExcepti

18、on this.doGet(request, response);/* * Initialization of the servlet. <br> * * 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 MyC

19、onnection() 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

20、"); 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

21、.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 Conne

22、ction 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

23、 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.getS

24、tring("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 ProductDa

25、o 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 = "sel

26、ect * 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

27、,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 in

28、t 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)

29、 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 Produc

30、t(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 do

31、uble 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，一定要正确配置servlet,下面我给出正确示例view plaincopy to clipboardprint?<?xml version=&qu

32、ot;1.0" encoding="UTF-8"?> <web-app version="2.4" xmlns="" xmlns:xsi="" xsi:schemaLocation=" "> <display-name>Benson</display-name> <servlet> <description>This is the description </description> <display-

33、name>This is the display name </display-name> <servlet-name>GetProductServlet</servlet-name> <servlet-class>servlet.GetProductServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>GetProductServlet</servlet-name> <url-pattern&g

34、t;/servlet/GetProductServlet</url-pattern> </servlet-mapping> <welcome-> <welcome-</welcome-file> </welcome-> <login-config> <auth-method>BASIC</auth-method> </login-config> </web-app> <?xml version="1.0" encoding="UTF-

35、8"?><web-app version="2.4" xmlns="" xmlns:xsi="" xsi:schemaLocation=" "> <display-name>Benson</display-name> <servlet> <description>This is the description </description> <display-name>This is the display name

36、</display-name> <servlet-name>GetProductServlet</servlet-name> <servlet-class>servlet.GetProductServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>GetProductServlet</servlet-name> <url-pattern>/servlet/GetProductServlet</

37、url-pattern> </servlet-mapping> <welcome-> <welcome-</welcome-file> </welcome-> <login-config> <auth-method>BASIC</auth-method> </login-config></web-app> 编写FLEX MXMLview plaincopy to clipboardprint?<?xml version="1.0" encoding=

38、"utf-8"?> <mx:Application xmlns:mx="" layout="absolute" creationComplete="send()"> <mx:HTTPService id="service" url="" method="GET" /> <mx:Script> <!-CDATA private function send():void /发送请求 service.send();

39、 -> </mx:Script> <mx:Canvas x="0" y="0" width="100%" height="100%"> <mx:DataGrid x="0" y="68" width="676" height="383" id="productdata" dataProvider="service.lastRduct&q

40、uot; fontFamily="Times New Roman" fontSize="16"> <mx:columns> <mx:DataGridColumn headerText="商品名称" dataField="name"/> <mx:DataGridColumn headerText="商品类别" dataField="type"/> <mx:DataGridColumn headerText="商品价格&q

41、uot; dataField="price"/> <mx:DataGridColumn headerText="剩余数量" dataField="num"/> </mx:columns> </mx:DataGrid> <mx:ApplicationControlBar x="0" y="0" height="70" width="676"> </mx:ApplicationControlBar&g

42、t; </mx:Canvas> </mx:Application> <?xml version="1.0" encoding="utf-8"?><mx:Application xmlns:mx="" layout="absolute" creationComplete="send()"><mx:HTTPService id="service" url="" method="GET" /> <mx:Script> <!-CDATA private function send():void /发送请求 service.send(); -> </mx:Script> <