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得到一天的最后时刻
public static Date getDateOneDayEnd(Date date) throws ParseException { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); calendar.set(Calendar.HOUR_OF_DAY, 23); calendar.set(Calendar.MINUTE, 59); calendar.set(Calendar.SECOND, 59); Date date1 = calendar.getTime(); return date1; } 得到一天的开始时刻
public static Date getOneDatefirst(Date date) throws ParseException { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); calendar.set(Calendar.HOUR_OF_DAY, 0); calendar.set(Calendar.MINUTE, 0); calendar.set(Calendar.SECOND, 0); Date date1 = calendar.getTime(); return date1; } 得到明天
public static Date addOnyDay(Date date) throws ParseException { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); calendar.set(Calendar.DAY_OF_MONTH, calendar.get(Calendar.DAY_OF_MONTH) + 1); Date date1 = calendar.getTime(); return date1; } 得到昨天
public static Date reduceOnyDay(Date date) throws ParseException { Calendar calendar = Calendar.getInstance(); calendar.setTime(date); calendar.set(Calendar.DAY_OF_MONTH, calendar.get(Calendar.DAY_OF_MONTH) - 1); Date date1 = calendar.getTime(); return date1; } 得到两个时间的间隔天数
public static long betweenTwoDays(Date date1, Date date2) { long a1 = date1.getTime(); long a2 = date2.getTime(); long a3 = a2 - a1; a3 = a3 / (3600 * 24 * 1000); return a3; } 解析日期字符串
public static final SimpleDateFormat DATE_TIME_FORMAT = new SimpleDateFormat("yyyyMMddHHmmss"); public static final SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("yyyyMMdd"); public static final SimpleDateFormat TIME_FORMAT = new SimpleDateFormat("HHmmss"); /** * @param: String * @return: java.util.Date */ public static Date parseDateTime(String dateTime) { try { return DATE_TIME_FORMAT.parse(dateTime); } catch (ParseException e) { e.printStackTrace(); } return null; } 用java8封装的新类实现
/** * * @param localDateTime * @return 一天的最后时刻 */ public static LocalDateTime getDateEnd(LocalDateTime localDateTime){ return localDateTime.withHour(23) .withMinute(59) .withSecond(59) .withNano(999999999); } /** * * @param localDateTime * @return 返回一天的开始时刻 */ public static LocalDateTime getDateFirst(LocalDateTime localDateTime){ return localDateTime.withHour(0) .withMinute(0) .withSecond(0) .withNano(0); } /** * * @param localDateTime * @return 返回明天 */ public static LocalDateTime plusOneDay(LocalDateTime localDateTime){ return localDateTime.plus(1, ChronoUnit.DAYS); } /** * * @param localDateTime * @return 返回昨天 */ public static LocalDateTime minuOneDay(LocalDateTime localDateTime){ return localDateTime.minus(1, ChronoUnit.DAYS); } /** * * @param localDateTime1 * @param localDateTime2 * @return 两个日期的间隔天数 */ public static int betweenTwoTime(LocalDateTime localDateTime1,LocalDateTime localDateTime2){ long secondone =localDateTime1.toEpochSecond(ZoneOffset.of("+8")); long secondtwo=localDateTime2.toEpochSecond(ZoneOffset.of("+8")); int day= (int) (secondtwo-secondone/(3600*24)); return day ; } 判断传入值是否为空
/**判断传入值是否为空*/ public static boolean isEmpty(String str) { if ( str == null || "".equals(str) || "null".equals(str) ) { return true; } else { return false; } } 判断传入字符串是否不为空
/** * * @param string * @return boolean */ public static boolean isNotEmpty(String string){ if(!"".equals(string)&&string!=null) return true; else return false; } 数字字符串转换为Integer数组(Integer.parseInt只能传入数字组成的字符串)，会去重
/** * String字符串转数字数组 * @param strings：传入的数组字符串 * @param separator：(自定义常量 )分隔符支持','及'&'等自定义分隔符 * */ public static Integer[] stringToArray(String strings,String separator){ try { List list = new ArrayList<>(); String[] strings1 = strings.split(separator); for (String str1 : strings1) { if(!NumberUtil.isEmpty(str1)){ Integer id = Integer.parseInt(str1); if(!list.contains(id)){ list.add(id); } } } return list.toArray(new Integer[list.size()]); } catch (RuntimeException e) { throw e; } } 注意传入的要是数字符字数组不是英文字符数组，stream迭代输出
@Test void test7(){ String s="31 23 12 3 123 1 23 12 31 23"; Integer integer[]=NumberUtil.stringToArray(s,Separator); Arrays.stream(integer).forEach(e->System.out.println(e)); } 字符串换为字符串数组
/** * * @param strings * @param separator * @return String[] */ public static String[] stringToArrayString(String strings,String separator){ try { String string[]=strings.split(separator); return string; }catch (RuntimeException e) { throw e; } } stream输出
@Test void test7(){ String s="31 23 12 3 123 1 23 12 31 23"; Integer integer[]=NumberUtil.stringToArray(s,Separator); Arrays.stream(integer).forEach(e->System.out.println(e)); String string[]=NumberUtil.stringToArrayString(s,Separator); Arrays.stream(string).forEach(e->System.out.println(e)); } 数字字符串转List
/** * * @param strings 数字字符串 * @param separator * @return List*/ public static List stringToIntegerList(String strings, String separator) { try { String[] splits = strings.split(separator); List list = new ArrayList<>(); for (String string : splits) { if (NumberUtil.isNotEmpty(string)) { Integer integer = Integer.parseInt(string); if (!list.contains(integer)) { list.add(integer); } } } return list; }catch (RuntimeException e){ throw e; } }
@Test void test8(){ String ss=" 23 12 3 123 12 312312 3 123 12"; List list=NumberUtil.stringToIntegerList(ss,Separator); list.stream().forEach(e->System.out.println(e)); } 字符串转List
/** * * @param strings * @param separator * @return List*/ public static List stringToListString(String strings,String separator){ try { List list=new ArrayList<>(); String[] splits = strings.split(separator); for(String string:splits){ if(NumberUtil.isNotEmpty(string)){ if(!list.contains(string)){ list.add(string); } } } return list; }catch (RuntimeException e){ throw e; } }
@Test void test9(){ String s="qeqe12c121xe123h12b31 23 12 21 321 3s 123 12 321 s3 123 s21 d1 23 123c0"; List list=NumberUtil.stringToListString(s,Separator); list.stream().forEach(e->System.out.println(e)); } 得到字符串的编码
/** * * @param string * @return encode */ public static String getEncoding(String string) { String encode = "GB2312"; try { if (string.equals(new String(string.getBytes(encode), encode))) { String s = encode; return s; } } catch (Exception exception) { } encode = "ISO-8859-1"; try { if (string.equals(new String(string.getBytes(encode), encode))) { String s1 = encode; return s1; } } catch (Exception exception1) { } encode = "UTF-8"; try { if (string.equals(new String(string.getBytes(encode), encode))) { String s2 = encode; return s2; } } catch (Exception exception2) { } encode = "GBK"; try { if (string.equals(new String(string.getBytes(encode), encode))) { String s3 = encode; return s3; } } catch (Exception exception3) { } return ""; @Test void test11(){ String s="werqew "; System.out.println(NumberUtil.getEncoding(s)); } 集合分割，比如长度为6的分割为长度为2的
/** * @param list * @param count 每一个子集合的长度 * @param* @return 分割后的集合的集合 */ public static List
> splitCollection(List list, int count) { if (list == null || count < 1) return null; List
> returnlist = new ArrayList<>(); int size = list.size();//总长 if (size < count) { returnlist.add(list); } else { int pre = size / count; int last = size % count; //前面每个pre for (int i = 0; i < pre; i++) { List itemList = new ArrayList<>(); for (int j = 0; j < count; j++) { itemList.add(list.get(i * count + j)); } returnlist.add(itemList); } //last的进行处理 if (last > 0) { List itemList = new ArrayList<>(); for (int i = 0; i < last; i++) { itemList.add(list.get(pre * count + i)); } returnlist.add(itemList); } } return returnlist; }
@Test void test12() { List list = new ArrayList<>(); list.add("as"); list.add("eeweqw"); list.add("qweqwe"); list.add("as"); list.add("12321"); list.add("dss"); List > lists = NumberUtil.splitCollection(list, 2); lists.stream().forEach(e -> System.out.println(e)); }
匹配正则表达式
//只含字母或者数字 public static final String REGEX_NUMBER_LETTER="^[A-Za-z0-9]+$"; public static boolean matchesRegex(String content, String regex) { Pattern pattern = Pattern.compile(regex); Matcher matcher = pattern.matcher(content); if (matcher.matches()) return true; else return false; } @Test void test13() { String s = "123j1231c12d3x1212"; System.out.println(RegexUtil.matchesRegex(s, RegexUtil.REGEX_NUMBER_LETTER)); } 转载地址：http://chrwi.baihongyu.com/