首先，设置日期：LocalDateTime dateTime = LocalDateTime.of(2019, Month.SEPTEMBER, 9, 10, 20); 现在，将日期时间格式化为ISO_WEEK_DATE格式：String str = dateTime.format(DateTimeFormatter.ISO_WEEK_DATE); 示例 import java.time.LocalDateTime; import java.time.Month; import java.time.format.DateTimeFormatter; public class Demo { public static void main(String[] args) { LocalDateTime dateTime = LocalDateTime.of(2019, Month.SEPTEMBER, 9, 10, 20); System.out.println("DateTime = "+dateTime); String str = dateTime.format(DateTimeFormatter.ISO_WEEK_DATE); System.out.println("Formatted date = "+str); } } 输出 DateTime = 2019-09-09T10:20 Formatted date = 2019-W37-1

首先，设置日期：LocalDateTime dateTime = LocalDateTime.of(2019, Month.JULY, 9, 10, 20); 现在，将日期时间格式化为ISO_DATE_TIME格式：String str = dateTime.format(DateTimeFormatter.ISO_DATE_TIME); 示例 import java.time.LocalDateTime; import java.time.Month; import java.time.format.DateTimeFormatter; public class Demo { public static void main(String[] args) { LocalDateTime dateTime = LocalDateTime.of(2019, Month.JULY, 9, 10, 20); System.out.println("DateTime = "+dateTime); String str = dateTime.format(DateTimeFormatter.ISO_DATE_TIME); System.out.println("Formatted date = "+str); } } 输出 DateTime = 2019-07-09T10:20 Formatted date = 2019-07-09T10:20:00

要格式化和显示日期时间，需要使用DateTimeFormatter并使用以下模式：DateTimeFormatter dtFormat = DateTimeFormatter.ofPattern("MMM dd yyyy hh:mm a z"); 上述z表示时区：MMM dd yyyy hh:mm a z 现在，对时区使用以下代码：ZonedDateTime dateTime = ZonedDateTime.now(); 示例 import java.time.ZonedDateTime; import java.time.format.DateTimeFormatter; public class Demo { public static void main(String[] argv) { DateTimeFormatter dtFormat = DateTimeFormatter.ofPattern("MMM dd yyyy hh:mm a z"); ZonedDateTime dateTime = ZonedDateTime.now(); String res = dateTime.format(dtFormat); System.out.printf("Date = %s %n", res); } } 输出 Date = Apr 14 2019 01:35 PM IST

要格式化和显示日期时间，需要使用DateTimeFormatter。格式样式为MEDIUM和SHORT：DateTimeFormatter formatter = DateTimeFormatter .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT); 显示格式化后的日期：formatter.format(LocalDateTime.now() 示例 import java.time.LocalDateTime; import java.time.format.DateTimeFormatter; import java.time.format.FormatStyle; public class Demo { public static void main(String[] args) { DateTimeFormatter formatter = DateTimeFormatter .ofLocalizedDateTime(FormatStyle.MEDIUM, FormatStyle.SHORT); System.out.println("Formatted Date = "+formatter.format(LocalDateTime.now())); } } 输出 Formatted Date = Apr 19, 2019, 1:27 PM

以下是我们的文件：Path p = Paths.get("E:/input.txt"); FileStore file = Files.getFileStore(p); 现在，逐一检查受支持的属性：FileAttributeView = file.supportsFileAttributeView(FileAttributeView.class) PosixFileAttributeView = file.supportsFileAttributeView(PosixFileAttributeView.class) BasicFileAttributeView = file.supportsFileAttributeView(BasicFileAttributeView.class) 示例 import java.nio.file.FileStore; import java.nio.file.Files; import java.nio.file.Path; import java.nio.file.Paths; import java.nio.file.attribute.BasicFileAttributeView; import java.nio.file.attribute.FileAttributeView; import java.nio.file.attribute.FileOwnerAttributeView; import java.nio.file.attribute.PosixFileAttributeView; public class Demo { public static void main(String[] args) throws Exception { Path p = Paths.get("E:/input.txt"); FileStore file = Files.getFileStore(p); System.out.println("FileAttributeView = " + file.supportsFileAttributeView(FileAttributeView.class)); System.out.println("PosixFileAttributeView = "+ file.supportsFileAttributeView(PosixFileAttributeView.class)); System.out.println("BasicFileAttributeView = "+ file.supportsFileAttributeView(BasicFileAttributeView.class)); System.out.println("FileOwnerAttributeView supported = "+ file.supportsFileAttributeView(FileOwnerAttributeView.class)); ... 阅读更多

假设以下是不只读的列表：List < Integer > list = new ArrayList < Integer > (); list.add(10); list.add(20); list.add(30); list.add(40); list.add(50); list.add(20); list.add(40); list.add(50); 将上述列表转换为只读：list = Collections.unmodifiableList(list); 转换后，您将无法再向列表中添加或删除元素。让我们来看一个例子：以下程序将报错，因为我们首先将列表更新为只读，然后尝试从中删除一个元素，这现在是不可能的。原因是我们已将列表转换为只读，您无法添加或删除元素... 阅读更多

要格式化并显示像这样的日期，即日/月/年，需要设置模式：dd/MM/yyyy 首先，设置一个LocalDate：LocalDate localDate = LocalDate.now(); 现在将日期格式化为'12/04/2019'：localDate.format(DateTimeFormatter.ofPattern("dd/MM/yyyy")) 示例 import java.time.LocalDate; import java.time.format.DateTimeFormatter; public class Demo { public static void main(String[] args) { LocalDate date = LocalDate.now(); System.out.println("Date = "+date); DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd/MM/yyyy"); System.out.println("Formatted Date = "+date.format(formatter)); } } 输出 Date = 2019-04-12 Formatted Date = 12/04/2019

要格式化并显示像这样的日期，即年月，需要设置模式：uuuuMM 首先，设置一个LocalDate：LocalDate localDate = LocalDate.now(); 现在将日期格式化为'201904'：localDate.format(DateTimeFormatter.ofPattern("uuuuMM")) 示例 import java.time.LocalDate; import java.time.format.DateTimeFormatter; public class Demo { public static void main(String[] args) { LocalDate localDate = LocalDate.now(); System.out.println("Date = "+localDate); System.out.println("Date (Year and Month) = "+localDate.format(DateTimeFormatter.ofPattern("uuuuMM"))); } } 输出 Date = 2019-04-19 Date (Year and Month) = 201904

假设以下是毫秒的声明：long millis = 5000000; 现在从毫秒获取小时、分钟和秒：long hours = TimeUnit.MILLISECONDS.toHours(millis); long minutes = TimeUnit.MILLISECONDS.toMinutes(millis) - (hours * 60); long seconds = TimeUnit.MILLISECONDS.toSeconds(millis) - ((hours * 60 * 60) + (minutes * 60)); 使用String.format()将上述内容转换为可读字符串。 示例 import java.util.concurrent.TimeUnit; public class Demo { public static void main(String[] argv){ long millis = 5000000; long hours = TimeUnit.MILLISECONDS.toHours(millis); long minutes = TimeUnit.MILLISECONDS.toMinutes(millis) - (hours * 60); long seconds = TimeUnit.MILLISECONDS.toSeconds(millis) - ((hours * ... 阅读更多

首先设置一个LocalDateTime：LocalDate date = LocalDate.now(); LocalTime time = LocalTime.now(); LocalDateTime dateTime = LocalDateTime.of(date, time); 现在，将LocalDateTime转换为LocalDate和LocalTime：LocalDate localDate = LocalDateTime.now().toLocalDate(); LocalTime localTime = LocalDateTime.now().toLocalTime(); 示例 import java.time.LocalDate; import java.time.LocalDateTime; import java.time.LocalTime; public class Demo { public static void main(String[] args) { LocalDate date = LocalDate.now(); LocalTime time = LocalTime.now(); LocalDateTime dateTime = LocalDateTime.of(date, time); System.out.println("DateTime = "+dateTime); LocalDate localDate = LocalDateTime.now().toLocalDate(); LocalTime localTime = LocalDateTime.now().toLocalTime(); System.out.println("Date = "+localDate); System.out.println("Time = ... 阅读更多