如何在java8中愉快地处理日期和时间java8新增了localdate和localtim

java8中的localdate和localtime用法举例如下:
这两个方法使我们可以方便的实现将旧的日期类转换为新的日期类,具体思路都是通过Instant当中介,然后通过Instant来创建LocalDateTime(这个类可以很容易获取LocalDate和LocalTime),新的日期类转旧的也是如此,将新的先转成LocalDateTime,然后获取Instant,接着转成Date,具体实现细节如下:
   
// 01. java.util.Date --> java.time.LocalDateTime
public void UDateToLocalDateTime() {
    java.util.Date date = new java.util.Date();
    Instant instant = date.toInstant();
    ZoneId zone = ZoneId.systemDefault();
    LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, zone);
}
     
// 02. java.util.Date --> java.time.LocalDate
public void UDateToLocalDate() {
    java.util.Date date = new java.util.Date();
    Instant instant = date.toInstant();
    ZoneId zone = ZoneId.systemDefault();
    LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, zone);
    LocalDate localDate = localDateTime.toLocalDate();
}
     
// 03. java.util.Date --> java.time.LocalTime
public void UDateToLocalTime() {
    java.util.Date date = new java.util.Date();
    Instant instant = date.toInstant();
    ZoneId zone = ZoneId.systemDefault();
    LocalDateTime localDateTime = LocalDateTime.ofInstant(instant, zone);
    LocalTime localTime = localDateTime.toLocalTime();
}

// 04. java.time.LocalDateTime --> java.util.Date
public void LocalDateTimeToUdate() {
    LocalDateTime localDateTime = LocalDateTime.now();
    ZoneId zone = ZoneId.systemDefault();
    Instant instant = localDateTime.atZone(zone).toInstant();
    java.util.Date date = Date.from(instant);
}

// 05. java.time.LocalDate --> java.util.Date
public void LocalDateToUdate() {
    LocalDate localDate = LocalDate.now();
    ZoneId zone = ZoneId.systemDefault();
    Instant instant = localDate.atStartOfDay().atZone(zone).toInstant();
    java.util.Date date = Date.from(instant);
}
     
// 06. java.time.LocalTime --> java.util.Date
public void LocalTimeToUdate() {
    LocalTime localTime = LocalTime.now();
    LocalDate localDate = LocalDate.now();
    LocalDateTime localDateTime = LocalDateTime.of(localDate, localTime);
    ZoneId zone = ZoneId.systemDefault();
    Instant instant = localDateTime.atZone(zone).toInstant();
    java.util.Date date = Date.from(instant);
}

猜你喜欢

转载自breakingbad.iteye.com/blog/2321492