Java中的LocalDateTime compareTo()方法

LocalDateTime compareTo() method in Java

可以使用Java中LocalDateTime类中的compareTo()方法比较两个LocalDateTime对象。此方法需要单个参数，即要比较的LocalDateTime对象。

如果第一个LocalDateTime对象大于第二个LocalDateTime对象，则返回正数；如果第一个LocalDateTime对象小于第二个LocalDateTime对象，则返回负数；如果两个LocalDateTime对象相等，则返回零。

演示此过程的程序如下：

例

现场演示

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import java.time.*;
public class Main {
public static void main(String[] args) {
LocalDateTime ldt1 = LocalDateTime.parse("2019-02-15T11:37:12");
LocalDateTime ldt2 = LocalDateTime.parse("2019-02-18T23:15:30");
System.out.println("The first LocalDateTime object is:" + ldt1);
System.out.println("The second LocalDateTime object is:" + ldt2);
int val = ldt1.compareTo(ldt2);
if(val > 0)
System.out.println("
The first LocalDateTime object is greater than the second LocalDateTime object");
else if(val < 0)
System.out.println("
The first LocalDateTime object is lesser than the second LocalDateTime object");
else
System.out.println("
The LocalDateTime objects are equal");
}
}

输出量

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The first LocalDateTime object is: 2019-02-15T11:37:12
The second LocalDateTime object is: 2019-02-18T23:15:30
The first LocalDateTime object is lesser than the second LocalDateTime object

现在让我们了解以上程序。

首先，显示两个LocalDateTime对象。然后使用compareTo()方法对它们进行比较，并使用if else语句显示结果。演示此代码段如下所示-

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LocalDateTime ldt1 = LocalDateTime.parse("2019-02-15T11:37:12");
LocalDateTime ldt2 = LocalDateTime.parse("2019-02-18T23:15:30");
System.out.println("The first LocalDateTime object is:" + ldt1);
System.out.println("The second LocalDateTime object is:" + ldt2);
int val = ldt1.compareTo(ldt2);
if(val > 0)
System.out.println("
The first LocalDateTime object is greater than the second LocalDateTime object");
else if(val < 0)
System.out.println("
The first LocalDateTime object is lesser than the second LocalDateTime object");
else
System.out.println("
The LocalDateTime objects are equal");