Java时间类型转换

String转Long

1	`Long` `long=new` `SimpleDateFormat("yyyyMMddHHmmss").parse(String).getTime();`

Long转String　

1	`String string =` `new` `SimpleDateFormat("yyyyMMddHHmmss").format(new` `Date(Long));`

String转Timestamp

1	`Timestamp.valueOf(String)`

Timestamp转String

1 2	`Timestamp ts =` `new` `Timestamp(System.currentTimeMillis());` `String string=new` `SimpleDateFormat("yyyy/MM/dd HH:mm:ss").format(ts);`

String转Date

1	`Date date=new` `SimpleDateFormat("yyyyMMddHHmmss").parse(String)`

Date转String

1	`String string=new` `SimpleDateFormat("yyyyMMddHHmmss").format(date)`

Date转Long

1	`Long` `long=date.getTime();`

Long转Date

1 2	`String string=new` `SimpleDateFormat("yyyyMMddHHmmss").format(new` `Date(Long));` `Date date=new` `SimpleDateFormat("yyyyMMddHHmmss").parse(string);`

Date转Timestamp

1	`Timestamp ts =` `new` `Timestamp(date.getTime());`

Timestamp转Date

Timestamp ts = new Timestamp(System.currentTimeMillis()); 
Date date=new Date();
date=ts;

Long转Timestamp

1 2	`Long time1=System.currentTimeMillis();` `Timestamp time=new` `Timestamp(time1);`

Timestamp转Long

1	`long` `now=t.getDateTime();`

注意：如果数据库是dateTime类型的，即使java代码中声明的是Timestamp，但还是用.getTime()方法来获取这个Long类型的时间。

MySql的时间类型有             Java中与之对应的时间类型
                 date                                              java.sql.Date
             Datetime                                       java.sql.Timestamp
            Timestamp                                     java.sql.Timestamp
            Time                                             java.sql.Time
            Year                                              java.sql.Date

所以，如果数据库是dateTime,则先用java转换成timestamp类型

Date date = new Date();//获得系统时间.
        String nowTime = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(date);//将时间格式转换成符合Timestamp要求的格式.
        Timestamp xx = Timestamp.valueOf(nowTime);

然后存入数据库