import java.util.concurrent.locks.ReentrantLock;
class NonReentrantLockExample {
private final ReentrantLock lock = new ReentrantLock();
public void foo() throws InterruptedException {
assert !lock.isHeldByCurrentThread() :
"lock is held by current thread";
lock.lock();
try {
// ...
threadUnsafeBar();
} finally {
lock.unlock();
}
}
public void bar() throws InterruptedException {
assert !lock.isHeldByCurrentThread() :
"lock is held by current thread";
lock.lock();
try {
threadUnsafeBar();
} finally {
lock.unlock();
}
}
private void threadUnsafeBar() {
assert lock.isHeldByCurrentThread() :
"caller must hold the lock first";
// ...
}
}
public class Main {
public static void main(String args[]) throws Exception {
new NonReentrantLockExample().foo();
}
}
