/*
* Copyright 2012 The Netty Project
*
* The Netty Project 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 io.netty.channel;
import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.socket.SocketChannelConfig;
import java.nio.ByteBuffer;
import java.nio.channels.WritableByteChannel;
import java.util.Map;
/**
* A set of configuration properties of a {@link Channel}.
* <p>
* Please down-cast to more specific configuration type such as
* {@link SocketChannelConfig} or use {@link #setOptions(Map)} to set the
* transport-specific properties:
* <pre>
* {@link Channel} ch = ...;
* {@link SocketChannelConfig} cfg = <strong>({@link SocketChannelConfig}) ch.getConfig();</strong>
* cfg.setTcpNoDelay(false);
* </pre>
*
* <h3>Option map</h3>
*
* An option map property is a dynamic write-only property which allows
* the configuration of a {@link Channel} without down-casting its associated
* {@link ChannelConfig}. To update an option map, please call {@link #setOptions(Map)}.
* <p>
* All {@link ChannelConfig} has the following options:
*
* <table border="1" cellspacing="0" cellpadding="6">
* <tr>
* <th>Name</th><th>Associated setter method</th>
* </tr><tr>
* <td>{@link ChannelOption#CONNECT_TIMEOUT_MILLIS}</td><td>{@link #setConnectTimeoutMillis(int)}</td>
* </tr><tr>
* <td>{@link ChannelOption#WRITE_SPIN_COUNT}</td><td>{@link #setWriteSpinCount(int)}</td>
* </tr><tr>
* <td>{@link ChannelOption#ALLOCATOR}</td><td>{@link #setAllocator(ByteBufAllocator)}</td>
* </tr><tr>
* <td>{@link ChannelOption#AUTO_READ}</td><td>{@link #setAutoRead(boolean)}</td>
* </tr>
* </table>
* <p>
* More options are available in the sub-types of {@link ChannelConfig}. For
* example, you can configure the parameters which are specific to a TCP/IP
* socket as explained in {@link SocketChannelConfig}.
*/
public interface ChannelConfig {
/**
* Return all set {@link ChannelOption}'s.
*/
Map<ChannelOption<?>, Object> getOptions();
/**
* Sets the configuration properties from the specified {@link Map}.
*/
boolean setOptions(Map<ChannelOption<?>, ?> options);
/**
* Return the value of the given {@link ChannelOption}
*/
<T> T getOption(ChannelOption<T> option);
/**
* Sets a configuration property with the specified name and value.
* To override this method properly, you must call the super class:
* <pre>
* public boolean setOption(ChannelOption<T> option, T value) {
* if (super.setOption(option, value)) {
* return true;
* }
*
* if (option.equals(additionalOption)) {
* ....
* return true;
* }
*
* return false;
* }
* </pre>
*
* @return {@code true} if and only if the property has been set
*/
<T> boolean setOption(ChannelOption<T> option, T value);
/**
* Returns the connect timeout of the channel in milliseconds. If the
* {@link Channel} does not support connect operation, this property is not
* used at all, and therefore will be ignored.
*
* @return the connect timeout in milliseconds. {@code 0} if disabled.
*/
int getConnectTimeoutMillis();
/**
* Sets the connect timeout of the channel in milliseconds. If the
* {@link Channel} does not support connect operation, this property is not
* used at all, and therefore will be ignored.
*
* @param connectTimeoutMillis the connect timeout in milliseconds.
* {@code 0} to disable.
*/
ChannelConfig setConnectTimeoutMillis(int connectTimeoutMillis);
/**
* Returns the maximum number of messages to read per read loop.
* a {@link ChannelInboundHandler#channelRead(ChannelHandlerContext, Object) channelRead()} event.
* If this value is greater than 1, an event loop might attempt to read multiple times to procure multiple messages.
*/
int getMaxMessagesPerRead();
/**
* Sets the maximum number of messages to read per read loop.
* If this value is greater than 1, an event loop might attempt to read multiple times to procure multiple messages.
*/
ChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead);
/**
* Returns the maximum loop count for a write operation until
* {@link WritableByteChannel#write(ByteBuffer)} returns a non-zero value.
* It is similar to what a spin lock is used for in concurrency programming.
* It improves memory utilization and write throughput depending on
* the platform that JVM runs on. The default value is {@code 16}.
*/
int getWriteSpinCount();
/**
* Sets the maximum loop count for a write operation until
* {@link WritableByteChannel#write(ByteBuffer)} returns a non-zero value.
* It is similar to what a spin lock is used for in concurrency programming.
* It improves memory utilization and write throughput depending on
* the platform that JVM runs on. The default value is {@code 16}.
*
* @throws IllegalArgumentException
* if the specified value is {@code 0} or less than {@code 0}
*/
ChannelConfig setWriteSpinCount(int writeSpinCount);
/**
* Returns {@link ByteBufAllocator} which is used for the channel
* to allocate buffers.
*/
ByteBufAllocator getAllocator();
/**
* Set the {@link ByteBufAllocator} which is used for the channel
* to allocate buffers.
*/
ChannelConfig setAllocator(ByteBufAllocator allocator);
/**
* Returns {@link RecvByteBufAllocator} which is used for the channel
* to allocate receive buffers.
*/
RecvByteBufAllocator getRecvByteBufAllocator();
/**
* Set the {@link ByteBufAllocator} which is used for the channel
* to allocate receive buffers.
*/
ChannelConfig setRecvByteBufAllocator(RecvByteBufAllocator allocator);
/**
* Returns {@code true} if and only if {@link ChannelHandlerContext#read()} will be invoked automatically so that
* a user application doesn't need to call it at all. The default value is {@code true}.
*/
boolean isAutoRead();
/**
* Sets if {@link ChannelHandlerContext#read()} will be invoked automatically so that a user application doesn't
* need to call it at all. The default value is {@code true}.
*/
ChannelConfig setAutoRead(boolean autoRead);
/**
* @deprecated From version 5.0, {@link Channel} will not be closed on write failure.
*
* Returns {@code true} if and only if the {@link Channel} will be closed automatically and immediately on
* write failure. The default is {@code false}.
*/
@Deprecated
boolean isAutoClose();
/**
* @deprecated From version 5.0, {@link Channel} will not be closed on write failure.
*
* Sets whether the {@link Channel} should be closed automatically and immediately on write faillure.
* The default is {@code false}.
*/
@Deprecated
ChannelConfig setAutoClose(boolean autoClose);
/**
* Returns the high water mark of the write buffer. If the number of bytes
* queued in the write buffer exceeds this value, {@link Channel#isWritable()}
* will start to return {@code false}.
*/
int getWriteBufferHighWaterMark();
/**
* Sets the high water mark of the write buffer. If the number of bytes
* queued in the write buffer exceeds this value, {@link Channel#isWritable()}
* will start to return {@code false}.
*/
ChannelConfig setWriteBufferHighWaterMark(int writeBufferHighWaterMark);
/**
* Returns the low water mark of the write buffer. Once the number of bytes
* queued in the write buffer exceeded the
* {@linkplain #setWriteBufferHighWaterMark(int) high water mark} and then
* dropped down below this value, {@link Channel#isWritable()} will start to return
* {@code true} again.
*/
int getWriteBufferLowWaterMark();
/**
* Sets the low water mark of the write buffer. Once the number of bytes
* queued in the write buffer exceeded the
* {@linkplain #setWriteBufferHighWaterMark(int) high water mark} and then
* dropped down below this value, {@link Channel#isWritable()} will start to return
* {@code true} again.
*/
ChannelConfig setWriteBufferLowWaterMark(int writeBufferLowWaterMark);
/**
* Returns {@link MessageSizeEstimator} which is used for the channel
* to detect the size of a message.
*/
MessageSizeEstimator getMessageSizeEstimator();
/**
* Set the {@link ByteBufAllocator} which is used for the channel
* to detect the size of a message.
*/
ChannelConfig setMessageSizeEstimator(MessageSizeEstimator estimator);
}