未调用UncaughtExceptionHandler

Question

我在Groovy / Java中使用UncaughtExceptionHandler遇到麻烦。

class UncaughtExceptionLogger implements Thread.UncaughtExceptionHandler {

    @Override
    void uncaughtException(Thread t, Throwable e) {
        //TODO do some logging;
        println "test";
    }

main..groovy

def main(){
    def handler = new UncaughtExceptionLogger();
    Thread.defaultUncaughtExceptionHandler = handler
    String s; 
    s.charAt(10); // causes a NullPointerException but the exception handler is not called 
}

main();

我为什么期望抛出NullPointerException时被调用的异常处理程序，但是这种情况不会发生。 我究竟做错了什么？

Answer 1

似乎必须使用单独的线程生成它：

class UncaughtExceptionLogger implements Thread.UncaughtExceptionHandler {
    @Override
    void uncaughtException(Thread t, Throwable e) {
        //TODO do some logging;
        println "test";
    }
}

def main(){
    Thread.defaultUncaughtExceptionHandler = new UncaughtExceptionLogger()
    String s;
    s.charAt(10); // causes a NullPointerException but the exception handler is not called
}

Thread.start {
  main()
}