由于线程本质的特性,我们并不能直接捕获从线程中逃逸的异常,一旦异常逃逸出run方法,那它就直接上控制台了。
我们只有通过设定回调类,传入回调的方法,这样才能够实现在外部处理线程中的异常:
/*
* 1.Thread的异常在Thread外面是捕获不到的
*/
public static void testThreadException(){
ExecutorService se=Executors.newCachedThreadPool();
try{
se.execute(new Runnable(){
public void run() {
throw new RuntimeException("TestException");
}
});
}catch(RuntimeException e){
//下面这条语句是执行不到的
System.out.println("Message: "+e.getMessage());
}
}
我们只有通过设定回调类,传入回调的方法,这样才能够实现在外部处理线程中的异常:
/*
* 为某个批次的线程设置异常捕获器,通过ThreadFactory完成
*/
public static void testCaughtThreadException(){
ExecutorService se=Executors.newCachedThreadPool(new ThreadFactory(){
public Thread newThread(Runnable r) {
Thread t=new Thread(r);
t.setUncaughtExceptionHandler(new UncaughtExceptionHandler(){
public void uncaughtException(Thread t, Throwable e) {
e.printStackTrace();
System.out.println("caught by myself"+e.getMessage());
}});
return t;
}
});
se.execute(new Runnable(){
public void run() {
throw new RuntimeException("TestException");
}
});
}
/*
* 设定静态的异常捕获器,为所有的Thread异常添加捕获机制
*/
static{
Thread.setDefaultUncaughtExceptionHandler(new UncaughtExceptionHandler(){
public void uncaughtException(Thread t, Throwable e) {
e.printStackTrace();
System.out.println("caught by myself"+e.getMessage());
}}
);
}
public static void testCaughtAllThreadException(){
ExecutorService se=Executors.newCachedThreadPool();
se.execute(new Runnable(){
public void run() {
throw new RuntimeException("TestException");
}
});
}