SelectionKeys remove异常

Set<SelectionKey> keys = selector.selectedKeys();
                    Iterator<SelectionKey> it = keys.iterator();
                    SelectionKey key = null;
                    while (it.hasNext()) {
                        key = it.next();
                        it.remove(); //错误处
                        SocketChannel sc = (SocketChannel) key.channel();
                        if (key.isValid()) {
                            if (key.isConnectable()) {
                                if (sc.finishConnect()) {
                                    sc.register(selector, SelectionKey.OP_READ);
                                    doWrite(sc);
                                }
                            } else {
                                System.out.println("connect to server failed");
                            }

                            if (key.isReadable()) {
                                ByteBuffer readBuffer = ByteBuffer.allocate(CommonConstants.B1024);
                                int readLength = sc.read(readBuffer);
                                if (readLength > 0) {
                                    readBuffer.flip();
                                    byte[] dataBytes = new byte[readBuffer.remaining()];
                                    readBuffer.get(dataBytes);
                                    String result = new String(dataBytes, Charset.forName(CommonConstants.UTF_8));
                                    System.out.println("received message from server [" + sc.getRemoteAddress()
                                            + "], contents: [" + result + "]");

                                    this.stop = true;
                                } else if (readLength < 0) {
                                    key.cancel();
                                    sc.close();
                                }
                            }
                        }
                    }

selector.selectedKeys()：

Keys may be removed from, but not directly added to, the selected-key set. Any attempt to add an object to the key set will cause an UnsupportedOperationException to be thrown.

selector.keys()：

The key set is not directly modifiable. A key is removed only after it has been cancelled and its channel has been deregistered. Any attempt to modify the key set will cause an UnsupportedOperationException to be thrown.

所以解决思路就是把错误处换成selectedKeys()

转载于:https://my.oschina.net/davidelena/blog/625323