/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package java.net; /** * Defines an interface for socket implementations to get and set socket * options. It is implemented by the classes {@code SocketImpl} and {@code * DatagramSocketImpl}. * * @see SocketImpl * @see DatagramSocketImpl */ public interface SocketOptions { /** * Number of seconds to wait when closing a socket if there * is still some buffered data to be sent. * *

If this option is set to 0, the TCP socket is closed forcefully and the * call to {@code close} returns immediately. * *

If this option is set to a value greater than 0, the value is interpreted * as the number of seconds to wait. If all data could be sent * during this time, the socket is closed normally. Otherwise the connection will be * closed forcefully. * *

Valid values for this option are in the range 0 to 65535 inclusive. (Larger * timeouts will be treated as 65535s timeouts; roughly 18 hours.) */ public static final int SO_LINGER = 128; /** * Integer timeout in milliseconds for blocking accept or read/receive operations (but not * write/send operations). A timeout of 0 means no timeout. Negative * timeouts are not allowed. * *

An {@code InterruptedIOException} is thrown if this timeout expires. */ public static final int SO_TIMEOUT = 4102; /** * This boolean option specifies whether data is sent immediately on this socket. * As a side-effect this could lead to low packet efficiency. The * socket implementation uses the Nagle's algorithm to try to reach a higher * packet efficiency if this option is disabled. */ public static final int TCP_NODELAY = 1; /** * This is an IPv4-only socket option whose functionality is subsumed by * {@link #IP_MULTICAST_IF} and not implemented on Android. */ public static final int IP_MULTICAST_IF = 16; /** * This option does not correspond to any Unix socket option and is not implemented on Android. */ public static final int SO_BINDADDR = 15; /** * This boolean option specifies whether a reuse of a local address is allowed even * if another socket is not yet removed by the operating system. It's only * available on a {@code MulticastSocket}. */ public static final int SO_REUSEADDR = 4; /** * The size in bytes of a socket's send buffer. This must be an integer greater than 0. * This is a hint to the kernel; the kernel may use a larger buffer. * *

For datagram sockets, it is implementation-defined whether packets larger than * this size can be sent. */ public static final int SO_SNDBUF = 4097; /** * The size in bytes of a socket's receive buffer. This must be an integer greater than 0. * This is a hint to the kernel; the kernel may use a larger buffer. * *

For datagram sockets, packets larger than this value will be discarded. */ public static final int SO_RCVBUF = 4098; /** * This boolean option specifies whether the kernel sends keepalive messages. */ public static final int SO_KEEPALIVE = 8; /** * This integer option specifies the value for the type-of-service field of the IPv4 header, * or the traffic class field of the IPv6 header. These correspond to the IP_TOS and IPV6_TCLASS * socket options. These may be ignored by the underlying OS. Values must be between 0 and 255 * inclusive. * *

See RFC 1349 for more about IPv4 * and RFC 2460 for more about IPv6. */ public static final int IP_TOS = 3; /** * This boolean option specifies whether the local loopback of multicast packets is * enabled or disabled. This option is enabled by default on multicast * sockets. Note that the sense of this option in Java is the * opposite of the underlying Unix {@code IP_MULTICAST_LOOP}. * See {@link MulticastSocket#setLoopbackMode}. */ public static final int IP_MULTICAST_LOOP = 18; /** * This boolean option can be used to enable broadcasting on datagram sockets. */ public static final int SO_BROADCAST = 32; /** * This boolean option specifies whether sending TCP urgent data is supported on * this socket or not. */ public static final int SO_OOBINLINE = 4099; /** * This integer option sets the outgoing interface for multicast packets * using an interface index. */ public static final int IP_MULTICAST_IF2 = 31; /** * Gets the value for the specified socket option. * * @return the option value. * @param optID * the option identifier. * @throws SocketException * if an error occurs reading the option value. */ public Object getOption(int optID) throws SocketException; /** * Sets the value of the specified socket option. * * @param optID * the option identifier. * @param val * the value to be set for the option. * @throws SocketException * if an error occurs setting the option value. */ public void setOption(int optID, Object val) throws SocketException; }