以下处理InterruptedException
的方式有什么区别?最好的方法是什么?
try{
//...
} catch(InterruptedException e) {
Thread.currentThread().interrupt();
}
或
try{
//...
} catch(InterruptedException e) {
throw new RuntimeException(e);
}
编辑:我也想知道这两个在哪些场景中使用。
最佳答案
What is the difference between the following ways of handling InterruptedException? What is the best way to do it?
您可能会问这个问题,因为您调用了一个抛出 InterruptedException
的方法。
首先,您应该看到 throws InterruptedException
是什么:方法签名的一部分以及调用您正在调用的方法的可能结果。因此,首先要接受 InterruptedException
是方法调用的完全有效结果这一事实。
现在,如果你调用的方法抛出了这样的异常,你的方法应该怎么做?您可以通过思考以下问题来找出答案:
你实现的方法抛出InterruptedException
有意义吗?换句话说,是InterruptedException
调用你的方法时的合理结果?
如果 yes,则
throws InterruptedException
应该是 您的 方法签名的一部分,并且您应该让异常传播(即根本不要捕获它)。Example: Your method waits for a value from the network to finish the computation and return a result. If the blocking network call throws an
InterruptedException
your method can not finish computation in a normal way. You let theInterruptedException
propagate.int computeSum(Server server) throws InterruptedException { // Any InterruptedException thrown below is propagated int a = server.getValueA(); int b = server.getValueB(); return a + b; }
如果 no,那么你不应该用
throws InterruptedException
声明你的方法,你应该(必须!)捕获异常。在这种情况下,有两点需要牢记:有人打断了你的话题。有人可能急于取消操作,优雅地终止程序,或其他任何事情。你应该对那个人有礼貌,然后毫不犹豫地从你的方法中返回。
即使 您的 方法可以设法在
InterruptedException
的情况下产生合理的返回值,但线程已被中断的事实可能仍然很重要.特别是,调用您的方法的代码可能对您的方法执行期间是否发生中断感兴趣。因此,您应该通过设置中断标志来记录发生中断的事实:Thread.currentThread().interrupt()
Example: The user has asked to print a sum of two values. Printing "
Failed to compute sum
" is acceptable if the sum can't be computed (and much better than letting the program crash with a stack trace due to anInterruptedException
). In other words, it does not make sense to declare this method withthrows InterruptedException
.void printSum(Server server) { try { int sum = computeSum(server); System.out.println("Sum: " + sum); } catch (InterruptedException e) { Thread.currentThread().interrupt(); // set interrupt flag System.out.println("Failed to compute sum"); } }
现在应该清楚了,仅仅执行 throw new RuntimeException(e)
是个坏主意。这对来电者不太礼貌。您可以发明一个新的运行时异常,但根本原因(有人希望线程停止执行)可能会丢失。
其他示例:
Implementing
Runnable
: As you may have discovered, the signature ofRunnable.run
does not allow for rethrowingInterruptedExceptions
. Well, you signed up on implementingRunnable
, which means that you signed up to deal with possibleInterruptedExceptions
. Either choose a different interface, such asCallable
, or follow the second approach above.
Calling
Thread.sleep
: You're attempting to read a file and the spec says you should try 10 times with 1 second in between. You callThread.sleep(1000)
. So, you need to deal withInterruptedException
. For a method such astryToReadFile
it makes perfect sense to say, "If I'm interrupted, I can't complete my action of trying to read the file". In other words, it makes perfect sense for the method to throwInterruptedExceptions
.String tryToReadFile(File f) throws InterruptedException { for (int i = 0; i < 10; i++) { if (f.exists()) return readFile(f); Thread.sleep(1000); } return null; }
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关于java - 在 Java 中处理 InterruptedException,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/3976344/