java访问数据库

package com.shiyanlou;import java.sql.*;public class JdbcTest {   // JDBC 驱动器名称 和数据库地址   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";     //数据库的名称为 EXAMPLE   static final String DB_URL = "jdbc:mysql://localhost/EXAMPLE";   //  数据库用户和密码   static final String USER = "root";   static final String PASS = "";   public static void main(String[] args) {       Connection conn = null;       Statement stmt = null;       try{           //注册JDBC 驱动程序           Class.forName("com.mysql.jdbc.Driver");           //打开连接           System.out.println("Connecting to database...");           conn = DriverManager.getConnection(DB_URL,USER,PASS);           //执行查询           System.out.println("Creating statement...");           stmt = conn.createStatement();           String sql;           sql = "SELECT id, name, age FROM Students";           ResultSet rs = stmt.executeQuery(sql);           //得到和处理结果集           while(rs.next()){               //检索               int id  = rs.getInt("id");               int age = rs.getInt("age");               String name = rs.getString("name");               //显示               System.out.print("ID: " + id);               System.out.print(", Age: " + age);               System.out.print(", Name: " + name);               System.out.println();           }           //清理环境           rs.close();           stmt.close();           conn.close();       }catch(SQLException se){           // JDBC 操作错误           se.printStackTrace();       }catch(Exception e){           // Class.forName 错误           e.printStackTrace();       }finally{           //这里一般用来关闭资源的           try{               if(stmt!=null)                   stmt.close();           }catch(SQLException se2){           }           try{               if(conn!=null)                   conn.close();           }catch(SQLException se){               se.printStackTrace();           }       }       System.out.println("Goodbye!");   }}