多线程 线程池异常处理
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示例：线程池执行过程中异常不输出，及解决方法测试
public class MyTest {
public static Runnable run(){
return ()->System.out.println("2/0="+2/0);
}
public static Runnable run2(){
return ()-> {
try {
System.out.println("2/0="+2/0);
}catch (Exception e){
e.printStackTrace();
}
};
}
public static void fun(){
ExecutorService executorService= Executors.newFixedThreadPool(5);
executorService.execute(run());
executorService.execute(run2());
executorService.shutdown();
}
public static void fun2(){
ExecutorService executorService= Executors.newFixedThreadPool(5);
executorService.submit(run());
executorService.submit(run2());
executorService.shutdown();
}
public static void fun3(){
ExecutorService executorService=new ThreadPoolExecutor(5,5,20, TimeUnit.SECONDS,
new ArrayBlockingQueue<Runnable>(10)){
@Override
public void execute(Runnable command) {
try {
super.execute(command);
}catch (Exception e){
e.printStackTrace();
}
}
};
executorService.execute(run());
executorService.execute(run2());
executorService.shutdown();
}
public static void fun4(){
ExecutorService executorService=new ThreadPoolExecutor(5,5,10L,TimeUnit.SECONDS,
new ArrayBlockingQueue<>(10)){
@Override
public Future<?> submit(Runnable task) {
return super.submit(()->{
try{
task.run();
}catch (Exception e){
e.printStackTrace();
}
});
}
};
executorService.submit(run());
executorService.submit(run2());
}
public static void fun5(){
ExecutorService executorService=new ThreadPoolExecutor(5,5,10l,TimeUnit.SECONDS,
new ArrayBlockingQueue<>(10)){
@Override
protected void afterExecute(Runnable r, Throwable t) {
super.afterExecute(r, t);
if (t!=null){
System.out.println("afterExecute："+t.getMessage());
}
}
};
executorService.execute(run());
executorService.execute(run2());
executorService.shutdown();
}
public static void fun6(){
ExecutorService executorService=new ThreadPoolExecutor(5,5,10l,TimeUnit.SECONDS,
new ArrayBlockingQueue<>(10)){
@Override
protected void afterExecute(Runnable r, Throwable t) {
super.afterExecute(r, t);
if (t!=null){
System.out.println("afterExecute："+t.getMessage());
}
}
};
executorService.submit(run());
executorService.submit(run2());
executorService.shutdown();
}
public static void main(String[] args){
fun();
//fun2();
//fun3();
//fun4();
//fun5();
//fun6();
}
}
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相关输出
fun()
Exception in thread "pool-1-thread-1" java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run$0(MyTest.java:8)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明：同步执行（execute）时，run()、run2()方法异常都有输出
fun2()
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明：异步执行（submit）时，run()方法不输出运行时异常、run2()方法使用try-catch语句块输出异常信息
fun3()
Exception in thread "pool-1-thread-1" java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run$0(MyTest.java:8)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明：自定义线程池，重载execute方法，与未重载execute方法执行输出一致
fun4()
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run$0(MyTest.java:8)
at threadtest.MyTest$2.lambda$submit$0(MyTest.java:65)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at threadtest.MyTest$2.lambda$submit$0(MyTest.java:65)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明：自定义线程池，重载submit方法，run()、run2()方法都输出异常信息
fun5()
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
afterExecute：/ by zero
Exception in thread "pool-1-thread-1" java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run$0(MyTest.java:8)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明： 重载afterExecute方法，同步执行，run()输出并抛出异常，抛出的异常由afterExecute输出；run2()输出异常，无异常信息抛出
fun6()
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$run2$1(MyTest.java:14)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
说明：重载afterExecute方法不能处理submit执行过程中的异常
总结：execute方法异常不需要处理可直接输出；submit使用try-catch语句块处理异常，或者重载submit方法进行处理
