本文实例为大家分享了Java日期处理工具类DateUtils的具体代码，供大家参考，具体内容如下

import java.sql.Timestamp; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; /** * <日期时间处理工具类> */ public class DateUtils { /** * Date format pattern this is often used. */ public static final String PATTERN_YMD = "yyyy-MM-dd"; /** * Date format pattern this is often used. */ public static final String PATTERN_YMDHMS="yyyy-MM-dd HH:mm:ss"; /** * Formats the given date according to the YMD pattern. * * @param date The date to format. * @return An YMD formatted date string. * * @see #PATTERN_YMD */ public static String formatDate(Date date) { return formatDate(date, PATTERN_YMD); } /** * Formats the given date according to the specified pattern. The pattern * must conform to that used by the {@link SimpleDateFormat simple date * format} class. * * @param date The date to format. * @param pattern The pattern to use for formatting the date. * @return A formatted date string. * * @throws IllegalArgumentException If the given date pattern is invalid. * * @see SimpleDateFormat */ public static String formatDate(Date date, String pattern) { if (date == null) throw new IllegalArgumentException("date is null"); if (pattern == null) throw new IllegalArgumentException("pattern is null"); SimpleDateFormat formatter = new SimpleDateFormat(pattern); return formatter.format(date); } /** * Parses a date value. The format used for parsing the date value are retrieved from * the default PATTERN_YMD. * * @param dateValue the date value to parse * * @return the parsed date * * @throws IllegalArgumentException If the given dateValue is invalid. */ public static Date parseDate(String dateValue) { return parseDate(dateValue, null); } /** * Parses the date value using the given date format. * * @param dateValue the date value to parse * @param dateFormat the date format to use * * @return the parsed date. if parse is failed , return null * * @throws IllegalArgumentException If the given dateValue is invalid. */ public static Date parseDate(String dateValue, String dateFormat) { if (dateValue == null) { throw new IllegalArgumentException("dateValue is null"); } if (dateFormat == null) { dateFormat = PATTERN_YMD; } SimpleDateFormat df = new SimpleDateFormat(dateFormat); Date result = null; try { result = df.parse(dateValue); } catch (ParseException pe) { pe.printStackTrace();// 日期型字符串格式错误 } return result; } /** * Adds a number of years to a date returning a new object. * The original date object is unchanged. * * @param date the date, not null * @param amount the amount to add, may be negative * @return the new date object with the amount added * @throws IllegalArgumentException if the date is null */ public static Date addYears(Date date, int amount) { return add(date, Calendar.YEAR, amount); } /** * Adds a number of years to a timestamp returning a new object. * The original timestamp object is unchanged. * * @param timestamp the timestamp, not null * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added * @throws IllegalArgumentException if the timestamp is null */ public static Timestamp addYears(Timestamp timestamp, int amount) { return add(timestamp, Calendar.YEAR, amount); } //----------------------------------------------------------------------- /** * Adds a number of months to a date returning a new object. * The original date object is unchanged. * * @param date the date, not null * @param amount the amount to add, may be negative * @return the new date object with the amount added * @throws IllegalArgumentException if the date is null */ public static Date addMonths(Date date, int amount) { return add(date, Calendar.MONTH, amount); } /** * Adds a number of months to a timestamp returning a new object. * The original timestamp object is unchanged. * * @param timestamp the timestamp, not null * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added * @throws IllegalArgumentException if the timestamp is null */ public static Timestamp addMonths(Timestamp timestamp, int amount) { return add(timestamp, Calendar.MONTH, amount); } //----------------------------------------------------------------------- /** * Adds a number of days to a date returning a new object. * The original date object is unchanged. * * @param date the date, not null * @param amount the amount to add, may be negative * @return the new date object with the amount added * @throws IllegalArgumentException if the date is null */ public static Date addDays(Date date, int amount) { return add(date, Calendar.DATE, amount); } /** * Adds a number of days to a timestamp returning a new object. * The original timestamp object is unchanged. * * @param timestamp the timestamp, not null * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added * @throws IllegalArgumentException if the timestamp is null */ public static Timestamp addDays(Timestamp timestamp, int amount) { return add(timestamp, Calendar.DATE, amount); } //----------------------------------------------------------------------- /** * Adds a number of minutes to a timestamp returning a new object. * The original timestamp object is unchanged. * * @param timestamp the timestamp, not null * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added * @throws IllegalArgumentException if the timestamp is null */ public static Timestamp addMinutes(Timestamp timestamp, int amount) { return add(timestamp, Calendar.MINUTE, amount); } /** * Adds a number of days to current time returning a new object. * * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added */ public static Timestamp addDays(int amount) { Calendar c = Calendar.getInstance(); c.add(Calendar.DATE, amount); return new Timestamp(c.getTimeInMillis()); } //----------------------------------------------------------------------- /** * Adds to a date returning a new object. * The original date object is unchanged. * * @param date the date, not null * @param calendarField the calendar field to add to * @param amount the amount to add, may be negative * @return the new date object with the amount added * @throws IllegalArgumentException if the date is null */ private static Date add(Date date, int calendarField, int amount) { if (date == null) { throw new IllegalArgumentException("The date must not be null"); } Calendar c = Calendar.getInstance(); c.setTime(date); c.add(calendarField, amount); return c.getTime(); } /** * Adds to a timestamp returning a new object. * The original timestamp object is unchanged. * * @param timestamp the timestamp, not null * @param calendarField the calendar field to add to * @param amount the amount to add, may be negative * @return the new timestamp object with the amount added * @throws IllegalArgumentException if the timestamp is null */ private static Timestamp add(Timestamp timestamp, int calendarField, int amount) { if (timestamp == null) { throw new IllegalArgumentException("The timestamp must not be null"); } Calendar c = Calendar.getInstance(); c.setTime(timestamp); c.add(calendarField, amount); return new Timestamp(c.getTimeInMillis()); } /** * <生成最小的当天日期值> * @return 最小的当天日期值 */ public static Timestamp now() { Calendar c = Calendar.getInstance(); c.set(Calendar.HOUR_OF_DAY, 0); c.set(Calendar.MINUTE, 0); c.set(Calendar.SECOND, 0); c.set(Calendar.MILLISECOND, 0); return new Timestamp(c.getTimeInMillis()); } /** This class should not be instantiated. */ private DateUtils() { } }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。