void setInterestOps(SctpChannelImpl channel, ChannelFuture future, int interestOps) { boolean changed = false; try { // interestOps can change at any time and at any thread. // Acquire a lock to avoid possible race condition. synchronized (channel.interestOpsLock) { Selector selector = this.selector; SelectionKey key = channel.channel.keyFor(selector); if (key == null || selector == null) { // Not registered to the worker yet. // Set the rawInterestOps immediately; RegisterTask will pick it up. channel.setRawInterestOpsNow(interestOps); return; } // Override OP_WRITE flag - a user cannot change this flag. interestOps &= ~Channel.OP_WRITE; interestOps |= channel.getRawInterestOps() & Channel.OP_WRITE; switch (CONSTRAINT_LEVEL) { case 0: if (channel.getRawInterestOps() != interestOps) { key.interestOps(interestOps); if (Thread.currentThread() != thread && wakenUp.compareAndSet(false, true)) { selector.wakeup(); } changed = true; } break; case 1: case 2: if (channel.getRawInterestOps() != interestOps) { if (Thread.currentThread() == thread) { key.interestOps(interestOps); changed = true; } else { selectorGuard.readLock().lock(); try { if (wakenUp.compareAndSet(false, true)) { selector.wakeup(); } key.interestOps(interestOps); changed = true; } finally { selectorGuard.readLock().unlock(); } } } break; default: throw new Error(); } if (changed) { channel.setRawInterestOpsNow(interestOps); } } future.setSuccess(); if (changed) { fireChannelInterestChanged(channel); } } catch (CancelledKeyException e) { // setInterestOps() was called on a closed channel. ClosedChannelException cce = new ClosedChannelException(); future.setFailure(cce); fireExceptionCaught(channel, cce); } catch (Throwable t) { future.setFailure(t); fireExceptionCaught(channel, t); } }