什么是最好的方法转换格式的字符串' 1月2日,2010年'到一个日期在Java?
最后,我希望将月、日和年分解为整数,以便我可以使用
Date date = new Date();
date.setMonth()..
date.setYear()..
date.setDay()..
date.setlong currentTime = date.getTime();
将日期转换为时间。
什么是最好的方法转换格式的字符串' 1月2日,2010年'到一个日期在Java?
最后,我希望将月、日和年分解为整数,以便我可以使用
Date date = new Date();
date.setMonth()..
date.setYear()..
date.setDay()..
date.setlong currentTime = date.getTime();
将日期转换为时间。
当前回答
在Java 8中,我们获得了一个新的日期/时间API (JSR 310)。
下面的方法可以用来解析Java 8中的日期而不依赖于Joda-Time:
String str = "January 2nd, 2010";
// if we 2nd even we have changed in pattern also it is not working please workout with 2nd
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MMMM Q, yyyy", Locale.ENGLISH);
LocalDate date = LocalDate.parse(str, formatter);
// access date fields
int year = date.getYear(); // 2010
int day = date.getDayOfMonth(); // 2
Month month = date.getMonth(); // JANUARY
int monthAsInt = month.getValue(); // 1
LocalDate是表示日期(没有时间)的标准Java 8类。如果要解析包含日期和时间信息的值,则应该使用LocalDateTime。对于带时区的值,请使用ZonedDateTime。两者都提供了类似于LocalDate的parse()方法:
LocalDateTime dateWithTime = LocalDateTime.parse(strWithDateAndTime, dateTimeFormatter);
ZonedDateTime zoned = ZonedDateTime.parse(strWithTimeZone, zoneFormatter);
DateTimeFormatter Javadoc中的格式化字符列表:
All letters 'A' to 'Z' and 'a' to 'z' are reserved as pattern letters.
The following pattern letters are defined:
Symbol Meaning Presentation Examples
------ ------- ------------ -------
G era text AD; Anno Domini; A
u year year 2004; 04
y year-of-era year 2004; 04
D day-of-year number 189
M/L month-of-year number/text 7; 07; Jul; July; J
d day-of-month number 10
Q/q quarter-of-year number/text 3; 03; Q3; 3rd quarter
Y week-based-year year 1996; 96
w week-of-week-based-year number 27
W week-of-month number 4
E day-of-week text Tue; Tuesday; T
e/c localized day-of-week number/text 2; 02; Tue; Tuesday; T
F week-of-month number 3
a am-pm-of-day text PM
h clock-hour-of-am-pm (1-12) number 12
K hour-of-am-pm (0-11) number 0
k clock-hour-of-am-pm (1-24) number 0
H hour-of-day (0-23) number 0
m minute-of-hour number 30
s second-of-minute number 55
S fraction-of-second fraction 978
A milli-of-day number 1234
n nano-of-second number 987654321
N nano-of-day number 1234000000
V time-zone ID zone-id America/Los_Angeles; Z; -08:30
z time-zone name zone-name Pacific Standard Time; PST
O localized zone-offset offset-O GMT+8; GMT+08:00; UTC-08:00;
X zone-offset 'Z' for zero offset-X Z; -08; -0830; -08:30; -083015; -08:30:15;
x zone-offset offset-x +0000; -08; -0830; -08:30; -083015; -08:30:15;
Z zone-offset offset-Z +0000; -0800; -08:00;
其他回答
此外,SimpleDateFormat对于某些客户端技术(如GWT)是不可用的。
使用Calendar.getInstance()是个好主意,您的要求是比较两个日期;长时间约会。
在处理SimpleDateFormat类时,重要的是要记住Date不是线程安全的,不能与多个线程共享单个Date对象。
“m”和“m”之间也有很大的区别,小写字母用于表示分钟,大写字母用于表示月。“d”和“d”也是一样。这可能会导致经常被忽视的细微错误。有关更多细节,请参阅Javadoc或Java中字符串转换为日期的指南。
试试这个
String date = get_pump_data.getString("bond_end_date");
DateFormat format = new SimpleDateFormat("yyyy-MM-dd", Locale.ENGLISH);
Date datee = (Date)format.parse(date);
字符串到日期的转换:
private Date StringtoDate(String date) throws Exception {
SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd");
java.sql.Date sqlDate = null;
if( !date.isEmpty()) {
try {
java.util.Date normalDate = sdf1.parse(date);
sqlDate = new java.sql.Date(normalDate.getTime());
} catch (ParseException e) {
throw new Exception("Not able to Parse the date", e);
}
}
return sqlDate;
}
我简陋的测试程序。我用它来摆弄格式化程序,查找我在日志文件中找到的长日期(但是谁把它们放在那里了……)
我的测试程序:
package be.test.package.time;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.TimeZone;
public class TimeWork {
public static void main(String[] args) {
TimeZone timezone = TimeZone.getTimeZone("UTC");
List<Long> longs = new ArrayList<>();
List<String> strings = new ArrayList<>();
//Formatting a date needs a timezone - otherwise the date get formatted to your system time zone.
//Use 24h format HH. In 12h format hh can be in range 0-11, which makes 12 overflow to 0.
DateFormat formatter = new SimpleDateFormat("dd-MM-yyyy HH:mm:ss.SSS");
formatter.setTimeZone(timezone);
Date now = new Date();
//Test dates
strings.add(formatter.format(now));
strings.add("01-01-1970 00:00:00.000");
strings.add("01-01-1970 00:00:01.000");
strings.add("01-01-1970 00:01:00.000");
strings.add("01-01-1970 01:00:00.000");
strings.add("01-01-1970 10:00:00.000");
strings.add("01-01-1970 12:00:00.000");
strings.add("01-01-1970 24:00:00.000");
strings.add("02-01-1970 00:00:00.000");
strings.add("01-01-1971 00:00:00.000");
strings.add("01-01-2014 00:00:00.000");
strings.add("31-12-1969 23:59:59.000");
strings.add("31-12-1969 23:59:00.000");
strings.add("31-12-1969 23:00:00.000");
//Test data
longs.add(now.getTime());
longs.add(-1L);
longs.add(0L); //Long date presentation at - midnight 1/1/1970 UTC - The timezone is important!
longs.add(1L);
longs.add(1000L);
longs.add(60000L);
longs.add(3600000L);
longs.add(36000000L);
longs.add(43200000L);
longs.add(86400000L);
longs.add(31536000000L);
longs.add(1388534400000L);
longs.add(7260000L);
longs.add(1417706084037L);
longs.add(-7260000L);
System.out.println("===== String to long =====");
//Show the long value of the date
for (String string: strings) {
try {
Date date = formatter.parse(string);
System.out.println("Formated date : " + string + " = Long = " + date.getTime());
} catch (ParseException e) {
e.printStackTrace();
}
}
System.out.println("===== Long to String =====");
//Show the date behind the long
for (Long lo : longs) {
Date date = new Date(lo);
String string = formatter.format(date);
System.out.println("Formated date : " + string + " = Long = " + lo);
}
}
}
测试结果:
===== String to long =====
Formated date : 05-12-2014 10:17:34.873 = Long = 1417774654873
Formated date : 01-01-1970 00:00:00.000 = Long = 0
Formated date : 01-01-1970 00:00:01.000 = Long = 1000
Formated date : 01-01-1970 00:01:00.000 = Long = 60000
Formated date : 01-01-1970 01:00:00.000 = Long = 3600000
Formated date : 01-01-1970 10:00:00.000 = Long = 36000000
Formated date : 01-01-1970 12:00:00.000 = Long = 43200000
Formated date : 01-01-1970 24:00:00.000 = Long = 86400000
Formated date : 02-01-1970 00:00:00.000 = Long = 86400000
Formated date : 01-01-1971 00:00:00.000 = Long = 31536000000
Formated date : 01-01-2014 00:00:00.000 = Long = 1388534400000
Formated date : 31-12-1969 23:59:59.000 = Long = -1000
Formated date : 31-12-1969 23:59:00.000 = Long = -60000
Formated date : 31-12-1969 23:00:00.000 = Long = -3600000
===== Long to String =====
Formated date : 05-12-2014 10:17:34.873 = Long = 1417774654873
Formated date : 31-12-1969 23:59:59.999 = Long = -1
Formated date : 01-01-1970 00:00:00.000 = Long = 0
Formated date : 01-01-1970 00:00:00.001 = Long = 1
Formated date : 01-01-1970 00:00:01.000 = Long = 1000
Formated date : 01-01-1970 00:01:00.000 = Long = 60000
Formated date : 01-01-1970 01:00:00.000 = Long = 3600000
Formated date : 01-01-1970 10:00:00.000 = Long = 36000000
Formated date : 01-01-1970 12:00:00.000 = Long = 43200000
Formated date : 02-01-1970 00:00:00.000 = Long = 86400000
Formated date : 01-01-1971 00:00:00.000 = Long = 31536000000
Formated date : 01-01-2014 00:00:00.000 = Long = 1388534400000
Formated date : 01-01-1970 02:01:00.000 = Long = 7260000
Formated date : 04-12-2014 15:14:44.037 = Long = 1417706084037
Formated date : 31-12-1969 21:59:00.000 = Long = -7260000