java - 可抛出的构造函数

Question

4 种类型的 Throwable 构造函数 是:-

Throwable() : Constructs a new throwable with null as its detail message.

Throwable(String message) : Constructs a new throwable with the specified detail message.

Throwable(String message, Throwable cause) : Constructs a new throwable with the specified detail message and cause.

Throwable(Throwable cause) : Constructs a new throwable with the specified cause and a detail message of (cause==null ? null : cause.toString())

在一段代码中，前两个构造函数类型工作正常，但其他两个类型报告编译时错误。

IOException e = new IOException();  //Working properly

ArithmeticException ae = new ArithmeticException("Top Layer");  //Working properly

ArithmeticException ae = new ArithmeticException("Top Layer", e);  //Not working

ArithmeticException ae = new ArithmeticException(e);  //Not working

最后两个声明报错

No suitable constructors found for ArithmeticException

我使用的是 JDK 8

为什么最后两个声明报错？ 另外我该如何让它们工作？

Answer 1

因为ArithmeticException是一个未经检查的异常并且来自RuntimeException

RuntimeException and its subclasses are unchecked exceptions. Unchecked exceptions do not need to be declared in a method or constructor's throws clause if they can be thrown by the execution of the method or constructor and propagate outside the method or constructor boundary.

来自ArithmeticException

没有如下所示的构造函数，这就是为什么它会给你编译时错误:

AithmeticException ae = new ArithmeticException("Top Layer", e);  //Not working
ae = new ArithmeticException(e);  //Not working

更好地使用RuntimeException为此:

RuntimeException ae = new RuntimeException("Top Layer", e);  
ae = new RuntimeException(e);