Java中的 IsoChronology dateNow(ZoneId) 方法与示例

Java.time.chrono.IsoChronology类的dateNow()方法用于根据Iso 日历系统从指定时区的系统时钟中获取当前本地日期。

句法：

public LocalDate dateNow(ZoneId zone)

参数：该方法以zone id的对象为参数。

返回值：该方法根据 Iso 日历系统从指定的时钟对象返回本地日期。

以下是说明dateNow()方法的示例：

示例 1：

// Java program to demonstrate
// dateNow() method
  
import java.util.*;
import java.io.*;
import java.time.*;
import java.time.chrono.*;
  
public class GFG {
    public static void main(String[] argv)
    {
        try {
            // creating and initializing LocalDate Object
            LocalDate hidate = LocalDate.now();
  
            // getting IsoChronology used in LocalDate
            IsoChronology crono = hidate.getChronology();
  
            // creating and initializing ZoneId object
            ZoneId id = ZoneId.systemDefault();
  
            // getting LocalDate for the
            // given zoneid object
            // by using dateNow() method
            LocalDate date = crono.dateNow(id);
  
            // display the result
            System.out.println("LocalDate is: "
                               + date);
        }
        catch (DateTimeException e) {
            System.out.println("passed parameter can"
                               + " not form a date");
            System.out.println("Exception thrown: " + e);
        }
    }
}

输出：

LocalDate is: 2020-03-08

示例 2：

// Java program to demonstrate
// dateNow() method
  
import java.util.*;
import java.io.*;
import java.time.*;
import java.time.chrono.*;
  
public class GFG {
    public static void main(String[] argv)
    {
        try {
            // creating and initializing LocalDate Object
            LocalDate hidate = LocalDate.now();
  
            // getting IsoChronology used in LocalDate
            IsoChronology crono = hidate.getChronology();
  
            // creating and initializing ZoneId object
            ZoneId id = ZoneId.of("Europe/Paris");
  
            // getting LocalDate for the
            // given zoneid object
            // by using dateNow() method
            LocalDate date = crono.dateNow(id);
  
            // display the result
            System.out.println("LocalDate is: "
                               + date);
        }
        catch (DateTimeException e) {
            System.out.println("passed parameter can"
                               + " not form a date");
            System.out.println("Exception thrown: " + e);
        }
    }
}

输出：

LocalDate is: 2020-03-08

参考： https://docs.oracle.com/javase/9/docs/api/ Java/time/chrono/IsoChronology.html#dateNow-java.time.ZoneId-