JDK8-时间API(十)

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jdk8的时间API是线程安全的，可以看下面的案例测试

package cn.wcj.jdk8.lambda.test;import java.text.DateFormat;import java.text.SimpleDateFormat;import java.util.Date;/** * * <p>Title:DateFormatThreadLocal </p>* <p>Description: 线程安全时间格式化</p>* <p>Company:Software College </p> * @author SuccessKey(WangCJ)* @date 2017年6月21日 上午9:21:21 */public class DateFormatThreadLocal {    private static final ThreadLocal<DateFormat> THREAD_DF=new ThreadLocal<DateFormat>(){        @Override        public DateFormat initialValue() {            return new SimpleDateFormat("yyyyMMdd")  ;        }    }  ;    public static final Date convert(String source)throws Exception{           return THREAD_DF.get().parse(source)   ;    }}

package cn.wcj.jdk8.lambda.test;import java.text.SimpleDateFormat;import java.time.DayOfWeek;import java.time.Duration;import java.time.Instant;import java.time.LocalDate;import java.time.LocalDateTime;import java.time.OffsetDateTime;import java.time.Period;import java.time.ZoneId;import java.time.ZoneOffset;import java.time.format.DateTimeFormatter;import java.time.temporal.TemporalAdjusters;import java.util.ArrayList;import java.util.Date;import java.util.List;import java.util.Set;import java.util.concurrent.Callable;import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.Future;import org.junit.Test;/** * * <p>Title:DateTest </p>* <p>Description:测试JDK8新时间API </p>* <p>Company:Software College </p> * @author SuccessKey(WangCJ)* @date 2017年6月21日 上午9:05:59 */public class DateTest {    //JDK7的时间API存在线程安全问题演示    //结果1 出现抢占造成结果不正确    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 6017    //  Wed Jun 21 00:00:00 CST 6017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Fri Jun 21 00:00:00 CST 2120    //  Sun Jun 21 00:00:00 CST 6201    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Sat Sep 21 00:00:00 CST 2193    //结果2  线程安全问题JUC    //java.util.concurrent.ExecutionException: java.lang.NumberFormatException    @Test    public void test1() throws Exception {        SimpleDateFormat sdf=new SimpleDateFormat("yyyyMMdd")   ;        Callable<Date> task=new Callable<Date>() {            @Override            public Date call() throws Exception {                return sdf.parse("20170621");            }        };        ExecutorService threadPool = Executors.newFixedThreadPool(10);        List<Future<Date>> resultList = new ArrayList<Future<Date>>();        for(int x=0;x<12;x++)            resultList.add(threadPool.submit(task))   ;        for (Future<Date> future : resultList) {            System.out.println(future.get());        }        threadPool.shutdown();    }    //使用ThreadLocal改进JDK7时间线程安全问题    //运行结果    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    //  Wed Jun 21 00:00:00 CST 2017    @Test    public void test2() throws Exception{        Callable<Date> task=new Callable<Date>() {            @Override            public Date call() throws Exception {                return DateFormatThreadLocal.convert("20170621") ;            }        };        ExecutorService threadPool = Executors.newFixedThreadPool(10);        List<Future<Date>> resultList = new ArrayList<Future<Date>>();        for (int i = 0; i <10; i++)             resultList.add(threadPool.submit(task)) ;        for (Future<Date> future : resultList)             System.out.println(future.get());        threadPool.shutdown();      }    //JDK8线程安全    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    //  2017-06-21    @Test    public void test3()throws Exception{        DateTimeFormatter dtf = DateTimeFormatter.ofPattern("yyyyMMdd");        Callable<LocalDate> task=()->LocalDate.parse("20170621", dtf)   ;        ExecutorService threadPool = Executors.newFixedThreadPool(10);        List<Future<LocalDate>> resultList = new ArrayList<Future<LocalDate>>();        for (int i = 0; i < 10; i++)             resultList.add(threadPool.submit(task))   ;        int len=resultList.size()   ;        for (int i = 0; i < len; i++) {            System.out.println(resultList.get(i).get());        }        threadPool.shutdown();       }    //LocalDate、LocalTime、LocalDateTime    @Test    public void test4()throws Exception{          LocalDateTime localDateTime = LocalDateTime.now()  ;          System.out.println(localDateTime)  ;          System.out.println("-------------------------");          LocalDateTime localDateTime2 = LocalDateTime.of(2017, 6, 21, 10, 29,30);          System.out.println(localDateTime2) ;          System.out.println("-------------------------");          LocalDateTime plusYears = localDateTime2.plusYears(1);          System.out.println(plusYears);          System.out.println("-------------------------");          LocalDateTime minusMonths = localDateTime2.minusMonths(3);          System.out.println(minusMonths);          System.out.println("-------------------------");          System.out.println(localDateTime.getYear());          System.out.println(localDateTime.getMonthValue());          System.out.println(localDateTime.getDayOfMonth());          System.out.println(localDateTime.getHour());          System.out.println(localDateTime.getMinute());          System.out.println(localDateTime.getSecond());    }    // Instant : 时间戳。 （使用 Unix 元年  1970年1月1日 00:00:00 所经历的毫秒值）    @Test    public void test5() {        Instant now = Instant.now()  ; //默认使用 UTC 时区        System.out.println(now)      ;        OffsetDateTime offsetDateTime = now.atOffset(ZoneOffset.ofHours(8)) ;        System.out.println(offsetDateTime) ;        System.out.println(now.getNano())  ;        Instant now2 = Instant.ofEpochSecond(5);        System.out.println(now2);    }    //Duration : 用于计算两个“时间”间隔    //Period : 用于计算两个“日期”间隔    @Test    public void test6() throws Exception{           Instant ins1 = Instant.now();           Thread.sleep(1000) ;           Instant ins2 = Instant.now();           System.out.println(Duration.between(ins1, ins2).getSeconds());           System.out.println("---------------------")  ;           LocalDate ld1 = LocalDate.of(2014, 9, 5)   ;           LocalDate ld2 = LocalDate.now()  ;           Period period = Period.between(ld1, ld2);           System.out.println(period.getYears());           System.out.println(period.getMonths());           System.out.println(period.getDays());    }    //TemporalAdjuster : 时间校正器    @Test    public void test7() {          LocalDateTime localDateTime = LocalDateTime.now()  ;          System.out.println(localDateTime);               LocalDateTime localDateTime2 = localDateTime.withDayOfMonth(10) ;          System.out.println(localDateTime2);          LocalDateTime localDateTime3 = localDateTime.with(TemporalAdjusters.next(DayOfWeek.FRIDAY));          System.out.println(localDateTime3);          //自定义:下一个工作日          LocalDateTime localDateTime5 = localDateTime.with((l)->{              LocalDateTime localDateTime4 = (LocalDateTime) l ;              DayOfWeek dayOfWeek=localDateTime4.getDayOfWeek();            if(dayOfWeek.equals(DayOfWeek.FRIDAY)){                return localDateTime4.plusDays(3);            }else if(dayOfWeek.equals(DayOfWeek.SATURDAY)){                return localDateTime4.plusDays(2);            }else{                return localDateTime4.plusDays(1);            }          });          System.out.println(localDateTime5);    }    //DateTimeFormatter : 解析和格式化日期或时间    @Test    public void test8() {        DateTimeFormatter dtf = DateTimeFormatter.ISO_LOCAL_DATE  ;        LocalDateTime localDateTime = LocalDateTime.now()   ;        String fmt = localDateTime.format(dtf)   ;        System.out.println(fmt)  ;        System.out.println("------------------------")    ;        DateTimeFormatter dtf2 = DateTimeFormatter                                      .ofPattern("yyyy年MM月dd日 HH:mm:ss E") ;        LocalDateTime localDateTime2 = LocalDateTime.now()   ;        System.out.println(localDateTime2);        String fmt2 = localDateTime2.format(dtf2)   ;        System.out.println(fmt2) ;        System.out.println("------------------------")    ;        LocalDateTime parse = LocalDateTime.parse(fmt2, dtf2)  ;        System.out.println(parse)  ;    }    //Asia/Shanghai    @Test    public void test9(){        Set<String> availableZoneIds = ZoneId.getAvailableZoneIds();        availableZoneIds.stream()                        .filter((t)->t.contains("Asia"))                        .sorted()                        .forEach(System.out::println);    }    @Test    public void test10(){         LocalDateTime localDateTime = LocalDateTime.now(ZoneId.of("Asia/Shanghai"))  ;         System.out.println(localDateTime)  ;    } }

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