Java date format 2016-02-25 05:38
We use SimpleDateFormat to format date in java. It allows you formatting(date -> string) and parsing(string -> date). Before using SimpleDateFormat you have to choose user-defined patterns for date-time formatting. The following pattern letters are defined (all other characters from 'A' to 'Z' and from 'a' to 'z' are reserved). You can use them define different patterns.
| Letter | Date or Time Component | Presentation | Examples |
|---|---|---|---|
| G | Era designator | Text | AD |
| y | Year | Year | 1996; 96 |
| Y | Week year | Year | 2009; 09 |
| M | Month in year | Month | July; Jul; 07 |
| w | Week in year | Number | 27 |
| W | Week in month | Number | 2 |
| D | Day in year | Number | 189 |
| d | Day in month | Number | 10 |
| F | Day of week in month | Number | 2 |
| E | Day name in week | Text | Tuesday; Tue |
| u | Day number of week (1 = Monday, ..., 7 = Sunday) | Number | 1 |
| a | Am/pm marker | Text | PM |
| H | Hour in day (0-23) | Number | 0 |
| k | Hour in day (1-24) | Number | 24 |
| K | Hour in am/pm (0-11) | Number | 0 |
| h | Hour in am/pm (1-12) | Number | 12 |
| m | Minute in hour | Number | 30 |
| s | Second in minute | Number | 55 |
| S | Millisecond | Number | 978 |
| z | Time zone | General time zone | Pacific Standard Time; PST; GMT-08:00 |
| Z | Time zone | RFC 822 time zone | -0800 |
| X | Time zone | ISO 8601 time zone | -08; -0800; -08:00 |
The following code show how to use SimpleDateFormat to format date
Date date = new Date();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy/MM/dd");
System.out.println(simpleDateFormat.format(date));
You can define pattern in constructor of SimpleDateFormat or use applyPattern method to applies the given pattern. The following code is same as above.
Date date = new Date();
SimpleDateFormat simpleDateFormat = new SimpleDateFormat();
simpleDateFormat.applyPattern("yyyy/MM/dd");
System.out.println(simpleDateFormat.format(date));
About parsing string to date you can see here.