マルチスレッドスレッドプールの例外処理
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例：スレッドプールの実行中に例外が出力されず、ソリューションテスト
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();
}
}
*************************
関連する出力
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)
注：同期的に実行（実行）すると、run（）およびrun2（）メソッドの例外が出力されます。
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$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
注：非同期で実行（送信）する場合、run（）メソッドはランタイム例外を出力せず、run2（）メソッドはtry-catchステートメントブロックを使用して例外情報を出力します。
fun3（）
Exception in thread "pool-1-thread-1" java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$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)
説明：カスタムスレッドプール、オーバーロードされた実行メソッド、アンロードされた実行メソッドの出力と一致
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$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:835)
説明：カスタムスレッドプール、オーバーロード送信メソッド、run（）、run2（）メソッドはすべて異常な情報を出力します
fun5（）
java.lang.ArithmeticException: / by zero
at threadtest.MyTest.lambda$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)
説明：afterExecuteメソッドのオーバーロード、同期実行、run（）出力および例外のスロー、スローされた例外はafterExecuteによって出力されます; run2（）出力例外、例外情報はスローされません
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)
注：オーバーロードされたafterExecuteメソッドは、送信の実行中に例外を処理できません
概要：executeメソッドの例外は、処理せずに直接出力できます。submitは、try-catchステートメントブロックを使用して例外を処理するか、submitメソッドをオーバーロードして処理します
