java - 哪些异常需要方法的 throws 语句？

Question

在 Java 中，有一些异常需要 throws 语句:

public void myMethod() throws IOException {
  throw new IOException("Error!");
}

而其他人则不然:

public void myOtherMethod() {
  throw new IllegalArgumentException("Error!");
}

public void myThirdMethod() {
  throw new Error("Error!");
}

如果没有throws，第一种方法将无法编译声明。

判断是否Exception的标准是什么？/Error需要 throws声明？

Answer 1

编译器检查和提示的异常在java中称为检查异常。

At compile time, the java compiler checks that a program contains handlers for checked exceptions. Java compiler analyzes by which checked exceptions can result from execution of a method or constructor.For each checked exception which is a possible result, the throws clause for the method or constructor must mention the class or its superclasses of that exception.

从 JLS 了解更多信息:http://docs.oracle.com/javase/specs/jls/se5.0/html/exceptions.html

IOException 是一个检查异常，因此 java 编译器要求您捕获它或抛出它。而 IllegalArgumentException 是一个运行时异常，编译器不会检查或提示。