在不使用框架的情况下，写的简单的jdbc 调用通用方法

package com.panie.dao;

import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;


public class localdao
{
    // 设置驱动变量(jdbc的驱动程序放在WEB-INF下的lib目录下)
    static String sDBDriver = "com.mysql.jdbc.Driver";
    // 创建连接,数据库名landingbj，连接mysql的用户名是root,密码为空(如果你的mysql有用户名和密码请填上你的用户名和密码)
    static String sConnStr = "jdbc:mysql://127.0.0.1:3306/landingbj?user=root&password=yourpwd";

    public static Connection getConn() {
        Connection conn = null;
        try {
            Class.forName(sDBDriver);// 加载驱动
            // 获得连接
            conn = DriverManager.getConnection(sConnStr);
        } catch (ClassNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return conn;
    }
    
    public int insertTable(String tablename,Object object)
    {
        Field fields [] = object.getClass().getDeclaredFields();
        StringBuffer sb = new StringBuffer();
        StringBuffer sb2 = new StringBuffer();
        sb.append("insert into ").append(tablename).append("(");
        sb2.append(" values(");
        List<Object> valueList = new ArrayList<Object>();
        for(int j = 0 ; j < fields.length; j++)
        {
            fields[j].setAccessible(true);
            try
            {
                String fieldName = fields[j].getName();
                String field = fieldName;
                int index = 0;
                for(int i = 0; i < fieldName.length(); i++) 
                { 
                     char c = fieldName.charAt(i); 
                     if (Character.isUpperCase(c)) 
                     {
                         index = fieldName.indexOf(c,index);
                         field = fieldName.substring(0,index)+"_"+fieldName.substring(index);
                     } 
                }
                if(fields[j].get(object)!=null)
                {
                   
                    sb.append(field).append(",");
                    sb2.append("?").append(",");
                    valueList.add(fields[j].get(object));
                }
            }
            catch (IllegalArgumentException e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            catch (IllegalAccessException e)
            {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        sb.deleteCharAt(sb.length()-1).append(")");
        sb2.deleteCharAt(sb2.length()-1).append(")");
        String sql = sb.toString()+sb2.toString();
        Object[] params = valueList.toArray();
        return executeUpdate(sql,params);
    }
    
    public int executeUpdate(String sql, Object[] params)
    {
        PreparedStatement ps = null;
        Connection conn = getConn();
        int result = 0;
        try
        {
            ps = conn.prepareStatement(sql);// 获得预处理对象
            // 判断SQL语句中是否有问号占位符
            if (params != null && params.length != 0)
            {
                // 如果存在问号占位符，在给问号占位符设置值
                for (int i = 0; i < params.length; i++)
                {
                    ps.setObject(i + 1, params[i]);
                    
                }
            }
            // 执行增、删、改SQL语句
            result = ps.executeUpdate();
        }
        catch (SQLException e)
        {
            e.printStackTrace();
        }
        finally
        {
            close(null,ps,conn);
        }
        return result;
    }
    
    public static void close(ResultSet rs,PreparedStatement ps,Connection conn) {
        try {
            if (rs != null) {
                rs.close();
            }
            if (ps != null) {
                ps.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    
}