Java中的 GregorianCalendar equals() 方法
Java .util.GregorianCalendar.equals()方法是Java中的一个内置函数,用于检查此GregorianCalendar实例与作为参数传递给函数的 Object 之间的相等性。仅当指定的 Object 是与此GregorianCalendar 实例具有相同时间值(距 Epoch 的毫秒偏移量)的 GregorianCalendar 对象时,它才返回 true。
句法:
public boolean equals(Object obj)
参数:该函数接受一个强制参数obj ,该参数将与此GregorianCalendar 实例进行比较。
返回值:仅当指定的 Object 是 GregorianCalendar 对象并且与此实例具有相同的时间值(距 Epoch 的毫秒偏移量)时,此方法才返回 true,否则返回 false。
例子:
Input : c1 = Mon Jul 23 23:46:14 UTC 2018, c2 = Mon Jul 23 23:46:14 UTC 2018
Output : true
Input : c1 = Mon Jul 23 23:46:14 UTC 2018, c2 = Sun Jul 24 00:02:52 UTC 2022
Output : false
下面的程序说明了Java.util.GregorianCalendar.equals()函数:
方案一:
Java
// Java Program to illustrate the equals() function
// of GregorianCalendar class
import java.io.*;
import java.util.*;
class GFG {
public static void main(String[] args)
{
// Create a new calendar
GregorianCalendar c1 = (GregorianCalendar)
GregorianCalendar.getInstance();
// Display the current date and time
System.out.println("Current Date and Time : "
+ c1.getTime());
// Create a second calendar equal to first one
GregorianCalendar c2 =
(GregorianCalendar)(Calendar)c1.clone();
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
// Adding 15 months to second calendar
c2.add(GregorianCalendar.MONTH, 15);
// Display the current date and time
System.out.println("Modified Date and Time : "
+ c2.getTime());
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
}
}
Java
// Java Program to illustrate the equals() function
// of GregorianCalendar class
import java.io.*;
import java.util.*;
class GFG {
public static void main(String[] args)
{
// Create a new calendar
GregorianCalendar c1 = (GregorianCalendar)
GregorianCalendar.getInstance();
// Display the current date and time
System.out.println("Current Date and Time : "
+ c1.getTime());
// Create a second calendar equal to first one
GregorianCalendar c2 =
(GregorianCalendar)(Calendar)c1.clone();
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
// Changing the Time Zone of c2
c2.setTimeZone(TimeZone.getTimeZone("CST"));
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
}
}
输出:
Current Date and Time : Fri Jul 27 12:05:05 UTC 2018
Both calendars are equal:true
Modified Date and Time : Sun Oct 27 12:05:05 UTC 2019
Both calendars are equal:false
方案二:
Java
// Java Program to illustrate the equals() function
// of GregorianCalendar class
import java.io.*;
import java.util.*;
class GFG {
public static void main(String[] args)
{
// Create a new calendar
GregorianCalendar c1 = (GregorianCalendar)
GregorianCalendar.getInstance();
// Display the current date and time
System.out.println("Current Date and Time : "
+ c1.getTime());
// Create a second calendar equal to first one
GregorianCalendar c2 =
(GregorianCalendar)(Calendar)c1.clone();
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
// Changing the Time Zone of c2
c2.setTimeZone(TimeZone.getTimeZone("CST"));
// Compare the two calendars
System.out.println("Both calendars are equal:"
+ c1.equals(c2));
}
}
输出:
Current Date and Time : Fri Jul 27 12:05:08 UTC 2018
Both calendars are equal:true
Both calendars are equal:false
参考: https: Java/util/GregorianCalendar.html#equals()