Java Properties clear()用法及代碼示例

Java.util.Properties.clear()方法用於從此Properties實例中刪除所有元素。使用clear()方法隻能從屬性中清除所有元素，而不會刪除屬性。換句話說，可以說clear()方法僅用於清空現有屬性。

用法:

public void clear()

參數：該方法不帶任何參數

返回值：該函數不返回任何值。

以下示例程序旨在說明Java.util.Properties.clear()方法。

示例1:

// Java code illustrating clear() method 
  
import java.util.*; 
  
class PropertiesDemo { 
    public static void main(String arg[]) 
    { 
        Properties gfg = new Properties(); 
        Set URL; 
        String str; 
  
        gfg.put("ide", 
                "ide.geeksforgeeks.org"); 
        gfg.put("contribute", 
                "contribute.geeksforgeeks.org"); 
        gfg.put("quiz", 
                "quiz.geeksforgeeks.org"); 
  
        // checking what's in table 
        System.out.println("Current Properties: "
                           + gfg.toString()); 
  
        System.out.println("\nClearing the Properties"); 
        gfg.clear(); 
  
        // checking what's in table now 
        System.out.println("New Properties: "
                           + gfg.toString()); 
    } 
}

輸出：

Current Properties: {contribute=contribute.geeksforgeeks.org, quiz=quiz.geeksforgeeks.org, ide=ide.geeksforgeeks.org}

Clearing the Properties
New Properties: {}

示例2:

// Java code illustrating clear() method 
  
import java.util.*; 
  
class PropertiesDemo { 
    public static void main(String arg[]) 
    { 
        Properties gfg = new Properties(); 
        Set URL; 
        String str; 
  
        gfg.put(1, "Geeks"); 
        gfg.put(2, "GeeksforGeeks"); 
        gfg.put(3, "Geek"); 
  
        // checking what's in table 
        System.out.println("Current Properties: "
                           + gfg.toString()); 
  
        System.out.println("\nClearing the Properties"); 
        gfg.clear(); 
  
        // checking what's in table now 
        System.out.println("New Properties: "
                           + gfg.toString()); 
    } 
}

輸出：

Current Properties: {3=Geek, 2=GeeksforGeeks, 1=Geeks}

Clearing the Properties
New Properties: {}

參考： https://docs.oracle.com/javase/9/docs/api/java/util/Properties.html#clear–

相關用法

注：本文由純淨天空篩選整理自Kirti_Mangal大神的英文原創作品 Properties clear() method in Java with Examples。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。