java calendar_Java Calendar clear（）方法与示例

素颜马尾好姑娘i 2023-03-05 12:59 15阅读 0赞

java calendar

## 日历类clear()方法 **(**Calendar Class clear() method**)** ##

**Syntax:**

**句法：**

public final void clear();
        public final void clear(int fi);

*  **clear() method** is available in java.util package.
    
    **clear()方法**在java.util包中可用。
 *  **clear() method** is used to set the value of all calendar fields because no particular field is passed in the method and the value is not defined so the Calendar class uses the default field for date and time.
    
    **clear()方法**用于设置所有日历字段的值，因为该方法中未传递任何特定字段且未定义该值，因此Calendar类使用默认字段作为日期和时间。
 *  **clear(int fi) method** is used to set the value of the given calendar field because the particular field(fi) is passed in the method and value is not defined so the Calendar class uses default field for date & time.
    
    **clear(int fi)方法**用于设置给定日历字段的值，因为在该方法中传递了特定的field( fi )，并且未定义值，因此Calendar类将默认字段用于日期和时间。
 *  These methods do not throw an exception at the time of setting the given field with the default value.
    
    在将给定字段设置为默认值时，这些方法不会引发异常。
 *  These are non-static methods, so it is accessible with the class object and if we try to access these methods with the class name then we will get an error.
    
    这些是非静态方法，因此可以通过类对象进行访问，如果尝试使用类名称访问这些方法，则会收到错误消息。

**Parameter(s):**

**参数：**

*  In the first case, clear() – it does not accept any parameter.
    
    在第一种情况下， clear() –它不接受任何参数。
 *  In the second case, clear(int fi) – represents the calendar field to set as not defined.
    
    在第二种情况下， clear(int fi) –表示要设置为未定义的日历字段。

**Return value:**

**返回值：**

In both the cases, the return type of the method is void, it returns nothing.

在这两种情况下，方法的返回类型都是void ，它什么也不返回。

**Example:**

**例：**

// Java Program to demonstrate the example of
    // void clear() method of Calendar
    
    import java.util.*;
    
    public class ClearOfCalendar {
        
        public static void main(String[] args) {
        
            // Instantiating a Calendar object
            Calendar ca = Calendar.getInstance();
    
            // Display current calendar
            System.out.println("ca.getTime(): " + ca.getTime());
    
            // By using clear(int fi) method is to 
            // clear the current value and sets the
            // undefined value of the month field 
            // in current calendar
            ca.clear(Calendar.MONTH);
    
            // Display Calendar
            System.out.println("ca.clear(Calendar.MONTH): " + ca.getTime());
    
            // By using clear() method is to 
            // clear the current value of all the fields and 
            // sets the undefined value of the fields 
            // in current calendar
            ca.clear();
    
            // Display Calendar
            System.out.println("ca.clear(): " + ca.getTime());
        }
    }

**Output**

**输出量**

ca.getTime(): Thu Jan 23 11:29:31 GMT 2020
    ca.clear(Calendar.MONTH): Thu Jan 23 11:29:31 GMT 2020
    ca.clear(): Thu Jan 01 00:00:00 GMT 1970

> 翻译自: [https://www.includehelp.com/java/calendar-clear-method-with-example.aspx][https_www.includehelp.com_java_calendar-clear-method-with-example.aspx]

java calendar

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