Throwable類initCause()方法 (Throwable Class initCause() method)

• initCause() Method is available in java.lang package.

  initCause()方法在java.lang包中可用。

• initCause() Method is used to instantiate the cause of this throwable to the given value and this method is invoked within the constructor immediately after that we throw a throwable object.

  initCause()方法用于將此throwable的原因實例化為給定值，并且在我們拋出throwable對象之后立即在構造函數中調用此方法。

• initCause() 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.

  initCause()方法是一種非靜態方法，只能通過類對象訪問，如果嘗試使用類名稱訪問該方法，則會收到錯誤消息。

• initCause() Method may throw an exception at the time of initializing cause.

  initCause()方法可能會在初始化原因時引發異常。

  • IllegalArgumentException – This exception may throw when the given argument is this object.IllegalArgumentException-如果給定參數是此對象，則可能引發此異常。
  • IllegalStateException – This exception may throw when the given argument was created with throwable or when this method called already on this throwable.IllegalStateException-當使用throwable創建給定參數時，或者在此throwable上已調用此方法時，可能會拋出此異常。

Syntax:

句法：

    public Throwable initCause(Throwable caus);

Parameter(s):

參數：

• Throwable caus – represents the cause it retrieve by using getCause() method and if it returns null then cause is non-existent or not known.

  可拋出的原因-表示使用getCause()方法檢索的原因，如果返回null，則原因不存在或未知。

Return value:

返回值：

The return type of the method is Throwable, it returns reference to this "Throwable" object.

方法的返回類型為Throwable ，它返回對此“ Throwable”對象的引用。

Example:

例：

// Java program to demonstrate the example 
// of Throwable initCause(Throwable caus)
// method of Throwable 
public class InitCause {
public static void main(String args[]) throws Exception {
try {
// calling div() method
div(100, 0);
} catch (ArithmeticException ex) {
// Display the exception cause why it is
//thrown
System.out.println("Exception Cause:" + ex.getCause());
}
}
// This method divide two numbers and will
// throw an exception
public static void div(int d1, int d2) throws Exception {
try {
int res = d1 / d2;
} catch (ArithmeticException ex) {
// creating an exception
ArithmeticException ae = new ArithmeticException();
// instantiate exception cause by using
//initCause() method
ae.initCause(ex);
// throw an exception with its cause
throw (ae);
}
}
}

Output

輸出量

Exception Cause:java.lang.ArithmeticException: / by zero

翻譯自: https://www.includehelp.com/java/throwable-initcause-method-with-example.aspx