flex通过blazeds与java实现增删改查 整个实现流程

1，建一个userdb库，再建userinfo表，字段：id(int),username(varchar),password(varchar)。
2，DBConnection.java
    package com.datainfo;  
 
  import java.sql.Connection;  
  import java.sql.DriverManager;  
  import java.sql.SQLException;  
 
public class DBConnection {  
    public static Connection getConnection() throws ClassNotFoundException,  
            SQLException {  
        Connection conn = null;  
        String driver = "com.mysql.jdbc.Driver";  
        String url = "jdbc:mysql://localhost:3306/userdb";      //不同数据库不同JDBC
        String username = "sa";  
        String password = "sasa";  
        Class.forName(driver);  
        conn = DriverManager.getConnection(url, username, password);  
        return conn;  
    }  
} 
3，User.java
    package com.datainfo;  
 
public class User {  
    private int id;  
    private String username;  
    private String password;  
 
    public User() {  
          
    }  
 
    /** 
     * @return the id 
     */ 
    public int getId() {