assubclass

類類asSubclass()方法 (Class class asSubclass() method)

• asSubclass() method is available in java.lang package.

  asSubclass()方法在java.lang包中可用。

• asSubclass() method casts this Class object to denote a subclass of the class denoted by the given Class object.

  asSubclass()方法強制轉換此Class對象，以表示由給定Class對象表示的類的子類。

• asSubclass() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.

  asSubclass()方法是一個非靜態方法，只能由類對象訪問，如果嘗試使用類名訪問該方法，則會收到錯誤消息。

• asSubclass() method may throw ClassCastException at the time of casting a Class.

  asSubclass()方法可能會在強制轉換Class時引發ClassCastException。

  ClassCastException: In this exception when this Class does not denote a subclass of the given class.

  ClassCastException：在此異常中，當此Class類不表示給定類的子類時。

Syntax:

句法：

    public Class asSubclass(Class class_name);

Parameter(s):

參數：

• Class class_name – represents the name of the class.

  類class_name –表示類的名稱。

Return value:

返回值：

The return type of this method is Class, it returns this Class object, cast to denote a subclass of the given Class object.

此方法的返回類型為Class ，它返回此Class對象，強制轉換為表示給定Class對象的子類。

Example:

例：

// Java program to demonstrate the example 
// of Class asSubclass (Class class_name) method of Class class
public class ParentClass {
public static void main(String[] args) throws Exception {
// Creating ParentClass and ChildClass instance
ParentClass pc = new ParentClass();
ParentClass cc = new ChildClass();
// Get Classname
Class parent = pc.getClass();
System.out.println("Parent Class: " + parent);
Class child = cc.getClass();
System.out.println("Child Class: " + child);
// We are denoting ChildClass of the given ParentClass object
Class subclass = child.asSubclass(parent);
System.out.println("child.asSubclass(parent): " + subclass);
}
}
class ChildClass extends ParentClass {
}

Output

輸出量

Parent Class: class ParentClass
Child Class: class ChildClass
child.asSubclass(parent): class ChildClass

翻譯自: https://www.includehelp.com/java/class-class-assubclass-method-with-example.aspx

assubclass