请考虑TIJ第4版的此代码
class SleepBlocked implements Runnable {
public void run() {
try {
TimeUnit.SECONDS.sleep(100);
} catch(InterruptedException e) {
print("InterruptedException");
}
print("Exiting SleepBlocked.run()");
}
}
class IOBlocked implements Runnable {
private InputStream in;
public IOBlocked(InputStream is) { in = is; }
public void run() {
try {
print("Waiting for read():");
in.read();
} catch(IOException e) {
if(Thread.currentThread().isInterrupted()) {
print("Interrupted from blocked I/O");
} else {
throw new RuntimeException(e);
}
}
print("Exiting IOBlocked.run()");
}
}
class SynchronizedBlocked implements Runnable {
public synchronized void f() {
while(true) // Never releases lock
Thread.yield();
}
public SynchronizedBlocked() {
new Thread() {
public void run() {
f(); // Lock acquired by this thread
}
}.start();
}
public void run() {
print("Trying to call f()");
f();
print("Exiting SynchronizedBlocked.run()");
}
}
public class Interrupting {
private static ExecutorService exec =
Executors.newCachedThreadPool();
static void test(Runnable r) throws InterruptedException{
Future<?> f = exec.submit(r);
TimeUnit.MILLISECONDS.sleep(100);
print("Interrupting " + r.getClass().getName());
f.cancel(true); // Interrupts if running
print("Interrupt sent to " + r.getClass().getName());
}
public static void main(String[] args) throws Exception {
test(new SleepBlocked());
test(new IOBlocked(System.in));
test(new SynchronizedBlocked());
TimeUnit.SECONDS.sleep(3);
print("Aborting with System.exit(0)");
System.exit(0);
}
}
这是输出
Interrupting SleepBlocked
InterruptedException
Exiting SleepBlocked.run()
Interrupt sent to SleepBlocked
Waiting for read():
Interrupting IOBlocked
Interrupt sent to IOBlocked
Trying to call f()
Interrupting SynchronizedBlocked
Interrupt sent to SynchronizedBlocked
Aborting with System.exit(0)
在这里你可以看到所有创建的线程终于被中断了(至少这是我的想法,因为没有人执行它的run方法持续)但是之后Bruce Eckel继续说
您不能中断尝试获取同步锁的任务或尝试执行I / O的任务。
或者中断意味着什么呢?
他也说过
SleepBlock是可中断阻塞的一个例子,而IOBlocked和SynchronizedBlocked是不间断阻塞。
这里的不间断阻挡是什么意思?谁能指定两者之间的差异?
他已经过时了,或者你的版本已经过时了。 NIO通过InterruptibleChannel
支持可中断的I / O,尽管由于Linux中断语义错误,它只是以相当无用的方式关闭了通道。
java.io
和java.net
I / O操作不受中断,并且您的问题中没有任何内容证明不是这样。如果他们是,你会在输出中看到"Interrupted from blocked I/O"
,而你没有。您的I / O线程仍然在in.read()
中被阻止。