Java中的日期 hashCode() 方法和示例

Java Date 类的hashCode()方法返回一个值，该值是该对象的哈希码。

句法：

public int hashCode()

参数：该函数不接受任何参数。

返回值：它返回此对象的 hashCode 值。

异常：该函数不抛出任何异常。

下面的程序演示了上述函数：

// Java code to demonstrate
// hashCode() function of Date class
  
import java.util.Date;
import java.util.Calendar;
public class GfG {
    // main method
    public static void main(String[] args)
    {
  
        // creating a Calendar object
        Calendar c1 = Calendar.getInstance();
  
        // set Month
        // MONTH starts with 0 i.e. ( 0 - Jan)
        c1.set(Calendar.MONTH, 11);
  
        // set Date
        c1.set(Calendar.DATE, 05);
  
        // set Year
        c1.set(Calendar.YEAR, 1996);
  
        // creating a date object with specified time.
        Date dateOne = c1.getTime();
  
        System.out.println("Date: " + dateOne);
  
        // Prints hash Code
        System.out.println("HashCode: "
                           + dateOne.hashCode());
    }
}

输出：

Date: Thu Dec 05 08:22:04 UTC 1996
HashCode: -629399711

// Java code to demonstrate
// hashCode() function of Date class
  
import java.util.Date;
import java.util.Calendar;
public class GfG {
    // main method
    public static void main(String[] args)
    {
  
        // creating a Calendar object
        Calendar c1 = Calendar.getInstance();
  
        // set Month
        // MONTH starts with 0 i.e. ( 0 - Jan)
        c1.set(Calendar.MONTH, 11);
  
        // set Date
        c1.set(Calendar.DATE, 21);
  
        // set Year
        c1.set(Calendar.YEAR, 1999);
  
        // creating a date object with specified time.
        Date dateOne = c1.getTime();
  
        System.out.println("Date: " + dateOne);
  
        // Prints hash Code
        System.out.println("HashCode: "
                           + dateOne.hashCode());
    }
}

输出：

Date: Tue Dec 21 08:22:09 UTC 1999
HashCode: 871724355