Java Calendar equals()用法及代码示例

equals() 方法比较两个对象是否相等，如果相等则返回 true。 equals() 方法在 Object 类中提供。因为对象类是java中所有其他类的超类。 Calendar 类继承了 equals() 方法。它将此(当前日历对象)日历与指定的对象进行比较。当且仅当参数是同一日历系统的 Calendar 对象，该对象在与此对象相同的 Calendar 参数下表示相同的时间值时，结果才为真。

用法

public boolean equals(Object object)

参数

对象：要比较的对象

它返回一个布尔值。

抛出

不要抛出任何异常。

例子1

import java.util.Calendar;
public class CalendarEqualsExample1 {
public static void main(String[] args) {
      // create a new calendar object
     Calendar cal1 =  (Calendar) Calendar.getInstance();
      // print the current date and time
      System.out.println("" + cal1.getTime());
      // create a second calendar object
        Calendar cal2 = (Calendar) Calendar.getInstance();
      // print cal2
      System.out.println("" + cal2.getTime());
      // compare the first and second calendar object
      System.out.println("Cal1 and Cal2 are equal:" + cal1.equals(cal2));
   }
}

输出：

Wed Aug 01 02:31:56 PDT 2018
Wed Aug 01 02:31:57 PDT 2018
Cal1 and Cal2 are equal:false

例子2

import java.util.Calendar;
public class CalendarEqualsExample2 {
public static void main(String[] args) {
      // create a new calendar object
    Calendar cal1 =  (Calendar) Calendar.getInstance();
      // print the current date and time
      System.out.println("" + cal1.getTime());
      // create clone of first calendar object
      Calendar cal2 = (Calendar) (Calendar) cal1.clone();
      // print cal2
      System.out.println("" + cal2.getTime());
      // compare the first calendar object and cloned calendar object
      System.out.println("Cal1 and Cal2 are equal:" + cal1.equals(cal2));    
   }
}

输出：

Wed Aug 01 02:34:20 PDT 2018
Wed Aug 01 02:34:20 PDT 2018
Cal1 and Cal2 are equal:true

例子3

import java.util.Calendar;
public class CalendarEqualsExample3 {
public static void main(String[] args) {
      // create a new calendar object
   Calendar cal1 =  (Calendar) Calendar.getInstance();
      // print the current date and time
      System.out.println("" + cal1.getTime());
      // create a clone of first calendar object
      Calendar cal2 = (Calendar) (Calendar) cal1.clone();
      // print cal2
      System.out.println("" + cal2.getTime());
      // change YEAR field of cloned calendar object
      cal2.add(Calendar.YEAR, 5);
      // compare the two calendars
      System.out.println("Cal1 and Cal2 are equal:" + cal1.equals(cal2));
   }
}

输出：

Wed Aug 01 02:36:22 PDT 2018
Wed Aug 01 02:36:22 PDT 2018
Cal1 and Cal2 are equal:false

相关用法

注：本文由纯净天空筛选整理自 Java Calendar equals() Method。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。