MySQL：
1》下载地址：http://www.mysql.com/products/connector/
2》
//jdbc:[数据库类型]://[ip地址]:[端口号]/[数据库名]
private String url = "jdbc:mysql://localhost:3306/userdata";
private String driver = "com.mysql.jdbc.Driver";
private String user = "root";
private String pass = "root123";
try{
Class.forName("com.mysql.jdbc.Driver");//加载驱动
}
catch(ClassNotFoundException e)
{
e.getException();
}
//insert into [表名](列名1,列名2) values(?,?)
//[]可以省略，()不可以，有几个列就有几个问号
String sql = "insert into userdata.logn(user_logn,user_password) values(?,?) ";//该字符串指出了SQL语句的结构
Connection cnn = DriverManager.getConnection(url,user,pass);//连接数据库
PreparedStatement prep = cnn.prepareStatement(sql);//创建准备好的语句
String a = "asdasdasd",b="123456" ;
prep.setString(1,a );
prep.setString(2, b);
prep.executeUpdate();//将数据写入数据库，也有可能引发SQL异常
cnn.close();