Provides you with a good time tool class datetime

This kind of inspiration comes from C #

Although there are some date4j on the internet, jar is too tangled. The source code can be inherited into your util package. As a Senior Programmer, I believe there are many good util tool classes, I also hope that through this sharing, the technical experts will be able to share their useful tools.

First look at the source code

/** Ansitech Development Platform (Java) SDK ** copyright (c) 2014, ansitech Network Technology Co ., ltd All Rights Reserved. * http://www.ansitech.com/java/sdk/ ** licensed under the Apache license, version 2.0 (the "License"); * you may not use this file license t in compliance with the license. * You may obtain a copy of the license at ** http://www.apache.org/licenses/LICENSE-2.0 ** unless required by applicable la W or agreed to in writing, software * distributed under the license is distributed on an "as is" basis, * Without warranties or conditions of any kind, either express or implied. * See the license for the specific language governing permissions and * limitations under the license. */package COM. ansitech. core. system; import Java. io. serializable; import Java. text. dateformat; import Java. text. parseexcep Tion; import Java. text. simpledateformat; import Java. util. calendar; import Java. util. date;/***** Date and Time ** <p> encapsulation of calendar, for ease of use </P> ** @ author qsyang * @ version 1.0 */public class datetime implements serializable {/*** yyyy-mm-dd hh: mm: SS format */public static final string default_date_time_format_pattern = "yyyy-mm-dd hh: mm: SS";/*** yyyy-mm-dd hh: MM format */public static final string default_date_t Ime_hhmm_format_pattern = "yyyy-mm-dd hh: mm "; /*** yyyy-mm-dd hh format */public static final string default_date_time_hh_format_pattern = "yyyy-mm-dd hh "; /*** yyyy-mm-dd format */public static final string default_date_format_pattern = "yyyy-mm-dd";/*** hh: mm: SS format */public static final string default_time_format_pattern = "HH: mm: SS";/*** hh: Mm format */public static final string default_time_hhmm _ Format_pattern = "HH: mm";/*** year * <p> you can use datetime. now (). get (datetime. year_field) to obtain the year of the current time </P> */public static final int year_field = Java. util. calendar. year;/* month * <p> you can use datetime. now (). get (datetime. month_field) to obtain the month of the current time </P> */public static final int month_field = Java. util. calendar. month;/*** day * <p> can be passed by datetime. now (). get (datetime. day_field) to get the day of the current time </P> */public static final int day _ Field = Java. util. calendar. date;/*** hour <p> you can use datetime. now (). get (datetime. to get the hour of the current time </P> */public static final int hour_field = Java. util. calendar. hour_of_day;/*** minute <p> you can use datetime. now (). get (datetime. minute_field) to obtain the minute of the current time </P> */public static final int minute_field = Java. util. calendar. minute;/*** seconds * <p> you can use datetime. now (). get (datetime. second_field) to obtain the seconds of the current time </P> */Public St Atic final int second_field = Java. util. calendar. second;/*** millisecond <p> can be passed through datetime. now (). get (datetime. millisecond_field) to obtain the current time in milliseconds </P> */public static final int millisecond_field = Java. util. calendar. millisecond; private Java. util. calendar C; // calendar class/*** get a datetime, which has not been initialized yet, indicating that the time is 00:00:00. 000 * <p> to obtain the current system time, use datetime. now (); </P> */Public datetime () {c = calendar. getinstance (); c. Clear ();}/*** set the time <p> to input a time object, will be converted to the datetime type </P> ** @ Param date time object */Public datetime (Java. util. date) {c = calendar. getinstance (); C. settime (date);}/*** set time <p> You can input a Calendar Object, will be converted to the datetime type </P> ** @ Param calendar Calendar Object */Public datetime (Java. util. calendar calendar) {This. C = calendar;}/*** get current system time ** @ return datetime current system time */public static datetime now () {calendar Cale Ndar = calendar. getinstance (); return New datetime (calendar);}/*** set the time in milliseconds. The time base is 00:00:00. 000; <p> for example, new datetime (1000) * Indicates 00:00:01. 000; <br> use a negative number to indicate the time before the base time </P> ** @ Param milliseconds millisecond */Public datetime (long milliseconds) {c = calendar ar. getinstance (); C. settimeinmillis (milliseconds);}/*** convert to date type ** @ return date time */public date todate () {return C. gettime ();}/* ** Convert to a Calendar Object ** @ return Calendar Object */Public Java. util. calendar tocalendar () {return C;}/*** converts to Java. SQL. date (yyyy-mm-dd) date ** @ return Java. SQL. date */Public Java. SQL. date tosqldate () {return New Java. SQL. date (C. gettimeinmillis ();}/*** converts to Java. SQL. time (HH: mm: SS) Time ** @ return Java. SQL. time */Public Java. SQL. time tosqltime () {return New Java. SQL. time (C. gettimeinmillis ());}/*** Convert to Java. SQL. timestamp (timestamp) ** @ return Java. SQL. timestamp timestamp */Public Java. SQL. timestamp tosqltimestamp () {return New Java. SQL. timestamp (C. gettimeinmillis ();}/*** parse time <p> convert to HH: mm: SS or hh: MM format </P> ** @ Param time string format time * @ return datetime Date and Time object */public static datetime parsetime (string time) throws Java. text. parseexception {try {return datetime. par Sedatetime (time, datetime. default_time_format_pattern);} catch (parseexception e) {return datetime. parsedatetime (time, datetime. default_time_hhmm_format_pattern );}} /*** parse the date <p> according to the default_date_format_pattern rule in datetime, convert it to the yyyy-mm-dd format </P> ** @ Param date string format date * @ return datetime date time class */public static datetime parsedate (string date) throws Java. text. parseexception {return datetime. parsedat Etime (date, datetime. default_date_format_pattern);}/*** parse the datetime <p> according to the default_date_time_format_pattern rule in datetime, convert it to yyyy-mm-dd * hh: mm: SS format </P> ** @ Param datetime string format date and time * @ return datetime Date and Time object */public static datetime parsedatetime (string datetime) throws Java. text. parseexception {datetime result = NULL; // try to press yyyy-mm-dd hh: mm: Ss to analyze try {result = datetime. parsedatetime (datetime, datetime. Default_date_time_format_pattern);} catch (parseexception e) {// resolution error result = NULL;} // try to analyze if (null = Result) by using yyyy-mm-dd hh: mm) {try {result = datetime. parsedatetime (datetime, datetime. default_date_time_hhmm_format_pattern);} catch (parseexception e) {// resolution error result = NULL ;}// try to analyze if (null = Result) by using yyyy-mm-dd hh) {try {result = datetime. parsedatetime (datetime, datetime. default_date _ Time_hh_format_pattern);} catch (parseexception e) {// resolution error result = NULL ;}// try to analyze if (null = Result) by yyyy-mm-dd) {try {result = datetime. parsedate (datetime);} catch (parseexception e) {// resolution error result = NULL;} // try to analyze by time if (null = Result) {result = datetime. parsetime (datetime);} return result;}/*** use the specified pattern to analyze the string <p> for the usage of pattern, see Java. text. simpledateformat </P> ** @ Param datetime String format date and time * @ Param pattern Date Parsing Rule * @ return datetime Date and Time object * @ see Java. text. simpledateformat */public static datetime parsedatetime (string datetime, string pattern) throws Java. text. parseexception {simpledateformat FMt = (simpledateformat) dateformat. getdateinstance (); FMT. applypattern (pattern); return New datetime (FMT. parse (datetime);}/*** convert to the default_date_format_pattern (yyyy-mm-dd) Format String ** @ Return yyyy-mm-dd format string */Public String todatestring () {return todatetimestring (datetime. default_date_format_pattern);}/*** convert to default_time_format_pattern (HH: mm: SS) Format String ** @ return hh: mm: SS format string */Public String totimestring () {return todatetimestring (datetime. default_time_format_pattern);}/*** converts it to a default_date_time_format_pattern (yyyy-mm-dd hh: mm: SS) Format String ** @ return yyyy-mm-d D hh: mm: SS format string */Public String todatetimestring () {return todatetimestring (datetime. default_date_time_format_pattern);}/*** use date to convert pattern <p> for the usage of pattern, see Java. text. simpledateformat </P> ** @ Param pattern Date Parsing Rule * @ return date and time string converted by Rule */Public String todatetimestring (string pattern) {simpledateformat FMt = (simpledateformat) dateformat. getdateinstance (); FMT. applypattern (pattern); Return FMT. format (C. gettime ();}/*** get the value of a metric of the time represented by datetime. ** @ Param field INT: <br> datetime. year_field -- returns the year <br> * datetime. month_field -- returns the month, 1 in December, 2 in December, and so on. <br> datetime. day_field -- * returns the current day (in this month) <br> datetime. hour_field -- returns the hour (in the current day), in the 24-hour format <br> * datetime. minute_field -- returns the number of minutes (in this hour) <br> datetime. second_field -- * returns the number of seconds (in this minute) <br> datetime. millisecond_field -- returns the number of milliseconds (in this second) * @ return int Field Value */Public int get (INT field) {// The month needs to be + 1 (the month starts from 0) if (datetime. month_field = field) {return C. get (field) + 1;} else {return C. get (field) ;}}/*** returns the number of milliseconds since. ** @ return long milliseconds */public long gettimeinmillis () {return C. gettimeinmillis ();}/*** set the field value ** @ Param field int to: <br> datetime. year_field -- year <br> * datetime. month_field-month, which starts from 1 in January <br> dateti Me. day_field -- * current day (in this month) <br> datetime. hour_field -- hour (in this day), in 24-hour format <br> * datetime. minute_field -- number of minutes (in this hour) <br> datetime. second_field -- * seconds (in this minute) <br> datetime. millisecond_field -- millisecond count (in this second) * @ Param value */Public void set (INT field, int value) {// The month needs to be-1 (the month starts from 0) if (datetime. month_field = field) {C. set (field, value-1);} else {C. set (field, value) ;}}/*** set the year, month, and day of the datetime date **@ Param year * @ Param month * @ Param day */Public void set (INT year, int month, int day) {set (datetime. year_field, year); Set (datetime. month_field, month); Set (datetime. day_field, day );} /*** set the year, month, day, and hour of the datetime date ** @ Param year * @ Param month * @ Param day * @ Param hour */Public void set (INT year, int month, int day, int hour) {set (year, month, day); Set (datetime. hour_field, ho UR );} /*** set the year, month, day, hour, and minute of the datetime date ** @ Param year * @ Param month * @ Param day * @ Param hour *@ param minute */Public void set (INT year, int month, int day, int hour, int minute) {set (year, month, day, hour); Set (datetime. minute_field, minute );} /*** set the year, month, day, hour, minute, and second of the datetime date ** @ Param year * @ Param month * @ Param day * @ Param hour * @ Param minute * @ Param second */Public void set (INT year, int month, int day, int hour, int minute, int second) {set (year, month, day, hour, minute ); set (datetime. second_field, second );} /*** set the year, month, day, hour, minute, second, or millisecond of the datetime date ** @ Param year * @ Param month * @ Param day * @ Param hour hour * @ Param minute * @ Param second * @ Param millisecond */Public void set (INT year, int month, int day, int hour, int minute, int Second, int millisecond) {set (year, month, day, hour, minute, second); Set (datetime. millisecond_field, millisecond);}/*** the addition of Field Values <p> Add () is very powerful. Add can calculate datetime fields. <Br> * If You Need to subtract a value, you can use a negative value, for example, add (field,-value ). <Br> * or call datetime. reduce (INT, INT) minus date </P> ** @ Param field int value: <br> datetime. year_field -- year <br> * datetime. month_field -- month, which starts from 1 in January <br> * datetime. day_field -- current day (in this month) <br> * datetime. hour_field -- hour (in this day), in 24-hour format <br> * datetime. minute_field -- number of minutes (in this hour) <br> * datetime. second_field -- number of seconds (in this minute) <br> * datetime. millisecond_field -- number of milliseconds (in this second) * @ Param amount number (if the number is smaller than 0, it is subtract) */Public voi D add (INT field, int amount) {C. add (field, amount);}/*** subtract Field Values <p> encapsulate the add () function. Add can calculate the fields in the calendar. <Br> * If You Need to subtract a value, you can use a negative value, for example, add (field,-value ). <Br> * For detailed usage, see calendar. add (INT, INT) </P> ** @ Param field int value: <br> datetime. year_field -- year <br> * datetime. month_field -- month, which starts from 1 in January <br> * datetime. day_field -- current day (in this month) <br> * datetime. hour_field -- hour (in this day), in 24-hour format <br> * datetime. minute_field -- number of minutes (in this hour) <br> * datetime. second_field -- number of seconds (in this minute) <br> * datetime. millisecond_field -- millisecond count (in this second) * @ Param amount count (if the number is smaller than 0, it is the sum) */Public void limit C E (INT field, int amount) {C. add (field,-amount);}/*** determines whether the time indicated by datetime is after the time indicated by the specified object, and returns the judgment result. <P> This method is equivalent to: compareto (when) *> 0 <br> true is returned only when is a datetime instance. Otherwise, false is returned. ** @ Param when: object to be compared * @ return if the datetime time is after the time indicated by when, true is returned; otherwise, false is returned. */Public Boolean after (object when) {If (when instanceof datetime) {return C. after (datetime) When ). c);} return C. after (when);}/*** determines whether the time indicated by datetime is before the time indicated by the specified object, and returns the judgment result. <P> This method is equivalent to: compareto (when) * <0 <br> true is returned only when is a datetime instance. Otherwise, false is returned. </P> ** @ Param when: object to be compared * @ return if the calendar time is earlier than the time indicated by when, true is returned; otherwise, false is returned. */Public Boolean before (object when) {If (when instanceof datetime) {return C. before (datetime) When ). c);} return C. before (when);}/*** create and return a copy of this object ** @ return date and time object */@ override public object clone () {return New datetime (calendar) C. clone ();}/*** returns the hash code of this calendar ** @ return the hash code value of this object. * @ See object */@ override public int hashcode () {return C. hashcode ();}/*** compares this datetime with the specified object. ** @ Param obj-object to be compared. * @ Return if this object is equal to OBJ, true is returned; otherwise, false is returned. * @ See object */@ override public Boolean equals (Object OBJ) {If (OBJ instanceof datetime) {return C. equals (datetime) OBJ ). tocalendar ();} If (OBJ instanceof calendar) {return C. equals (OBJ);} If (OBJ instanceof Java. util. date) {return C. gettime (). equals (OBJ) ;}return false ;}}

Next let's take a look at how to use it:

Obtain the current system time: datetime. Now (); returns a datetime object.

A datetime object can be converted into various date formats we need,

Example: Java. util. Date

DateTime.now().toDate();

You may also think that this writing method is not directly new date (); isn't it fast.

In many cases, a string needs to be converted to a java. util. date object. What should we do?

<pre name="code" class="java">new DateTime("2014-10-29").toDate();

Of course.

new DateTime("2014-10-29 15:19:23").toDate();

Here is only the basic usage. In other cases, java. util. date is converted into a string format.

We may usually use simpledateformat, but this is too troublesome. Let's look at the simple method.

new DateTime(new Date()).toDateString();

Returns a string in the format.

new DateTime(new Date()).toDateTimeString();

The returned string is a string in the format of 15:23:23.

What should we do if we need a format similar to October 29, 2014 or October 29, 2014?

New datetime (new date ()). todatetimestring ("mm DD, YYYY"); New datetime (new date ()). todatetimestring ("mm minute SS seconds on mm dd, YYYY ");

That's all!

There are many other functions. I will not give them one by one here. If you think it is good, please support them and leave a comment or share it with other friends, let more people know.

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Provides you with a good time tool class datetime