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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
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*
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package com.sun.nio.sctp;
import java.net.SocketAddress;
/**
* The {@code MessageInfo} class provides additional ancillary information about
* messages.
*
* <P> Received SCTP messages, returned by
* {@link SctpChannel#receive SctpChannel.receive} and {@link
* SctpMultiChannel#receive SctpMultiChannel.receive},
* return a {@code MessageInfo} instance that can be queried to determine
* ancillary information about the received message. Messages being sent should
* use one of the {@link #createOutgoing(java.net.SocketAddress,int)
* createOutgoing} methods to provide ancillary data for the message being
* sent, and may use the appropriate setter methods to override the default
* values provided for {@link #isUnordered() unordered}, {@link #timeToLive()
* timeToLive}, {@link #isComplete() complete} and {@link #payloadProtocolID()
* payloadProtocolID}, before sending the message.
*
* <P> For out going messages the {@code timeToLive} parameter is a time period
* that the sending side SCTP stack may expire the message if it has not been
* sent. This time period is an indication to the stack that the message is no
* longer required to be sent after the time period expires. It is not a hard
* timeout and may be influenced by whether the association supports the partial
* reliability extension, <a href=http://www.ietf.org/rfc/rfc3758.txt>RFC 3758
* </a>.
*
* <P> {@code MessageInfo} instances are not safe for use by multiple concurrent
* threads. If a MessageInfo is to be used by more than one thread then access
* to the MessageInfo should be controlled by appropriate synchronization.
*
* @since 1.7
*/
public abstract class MessageInfo {
/**
* Initializes a new instance of this class.
*/
protected MessageInfo() {}
/**
* Creates a {@code MessageInfo} instance suitable for use when
* sending a message.
*
* <P> The returned instance will have its {@link #isUnordered() unordered}
* value set to {@code false}, its {@link #timeToLive() timeToLive} value
* set to {@code 0}, its {@link #isComplete() complete} value set
* to {@code true}, and its {@link #payloadProtocolID() payloadProtocolID}
* value set to {@code 0}. These values, if required, can be set through
* the appropriate setter method before sending the message.
*
* @param address
* For a connected {@code SctpChannel} the address is the
* preferred peer address of the association to send the message
* to, or {@code null} to use the peer primary address. For an
* {@code SctpMultiChannel} the address is used to determine
* the association, or if no association exists with a peer of that
* address then one is setup.
*
* @param streamNumber
* The stream number that the message will be sent on
*
* @return The outgoing message info
*
* @throws IllegalArgumentException
* If the streamNumber is negative or greater than {@code 65536}
*/
public static MessageInfo createOutgoing(SocketAddress address,
int streamNumber) {
if (streamNumber < 0 || streamNumber > 65536)
throw new IllegalArgumentException("Invalid stream number");
return new sun.nio.ch.sctp.MessageInfoImpl(null, address, streamNumber);
}
/**
* Creates a {@code MessageInfo} instance suitable for use when
* sending a message to a given association. Typically used for
* {@code SctpMultiChannel} when an association has already been setup.
*
* <P> The returned instance will have its {@link #isUnordered() unordered}
* value set to {@code false}, its {@link #timeToLive() timeToLive} value
* set to {@code 0}, its {@link #isComplete() complete} value set
* to {@code true}, and its {@link #payloadProtocolID() payloadProtocolID}
* value set to {@code 0}. These values, if required, can be set through
* the appropriate setter method before sending the message.
*
* @param association
* The association to send the message on
*
* @param address
* The preferred peer address of the association to send the message
* to, or {@code null} to use the peer primary address
*
* @param streamNumber
* The stream number that the message will be sent on.
*
* @return The outgoing message info
*
* @throws IllegalArgumentException
* If {@code association} is {@code null}, or the streamNumber is
* negative or greater than {@code 65536}
*/
public static MessageInfo createOutgoing(Association association,
SocketAddress address,
int streamNumber) {
if (association == null)
throw new IllegalArgumentException("association cannot be null");
if (streamNumber < 0 || streamNumber > 65536)
throw new IllegalArgumentException("Invalid stream number");
return new sun.nio.ch.sctp.MessageInfoImpl(association,
address, streamNumber);
}
/**
* Returns the source socket address if the message has been received,
* otherwise the preferred destination of the message to be sent.
*
* @return The socket address, or {@code null} if this instance is to be
* used for sending a message and has been construced without
* specifying a preferred destination address
*
*/
public abstract SocketAddress address();
/**
* Returns the association that the message was received on, if the message
* has been received, otherwise the association that the message is to be
* sent on.
*
* @return The association, or {@code null} if this instance is to be
* used for sending a message and has been construced using the
* the {@link #createOutgoing(SocketAddress,int)
* createOutgoing(SocketAddress,int)} static factory method
*/
public abstract Association association();
/**
* Returns the number of bytes read for the received message.
*
* <P> This method is only appicable for received messages, it has no
* meaning for messages being sent.
*
* @return The number of bytes read, {@code -1} if the channel is an {@link
* SctpChannel} that has reached end-of-stream, otherwise
* {@code 0}
*/
public abstract int bytes();
/**
* Tells whether or not the message is complete.
*
* <P> For received messages {@code true} indicates that the message was
* completely received. For messages being sent {@code true} indicates that
* the message is complete, {@code false} indicates that the message is not
* complete. How the send channel interprets this value depends on the value
* of its {@link SctpStandardSocketOptions#SCTP_EXPLICIT_COMPLETE
* SCTP_EXPLICIT_COMPLETE} socket option.
*
* @return {@code true} if, and only if, the message is complete
*/
public abstract boolean isComplete();
/**
* Sets whether or not the message is complete.
*
* <P> For messages being sent {@code true} indicates that
* the message is complete, {@code false} indicates that the message is not
* complete. How the send channel interprets this value depends on the value
* of its {@link SctpStandardSocketOptions#SCTP_EXPLICIT_COMPLETE
* SCTP_EXPLICIT_COMPLETE} socket option.
*
* @param complete
* {@code true} if, and only if, the message is complete
*
* @return This MessageInfo
*
* @see MessageInfo#isComplete()
*/
public abstract MessageInfo complete(boolean complete);
/**
* Tells whether or not the message is unordered. For received messages
* {@code true} indicates that the message was sent non-ordered. For
* messages being sent {@code true} requests the un-ordered delivery of the
* message, {@code false} indicates that the message is ordered.
*
* @return {@code true} if the message is unordered, otherwise
* {@code false}
*/
public abstract boolean isUnordered();
/**
* Sets whether or not the message is unordered.
*
* @param unordered
* {@code true} requests the un-ordered delivery of the message,
* {@code false} indicates that the message is ordered.
*
* @return This MessageInfo
*
* @see MessageInfo#isUnordered()
*/
public abstract MessageInfo unordered(boolean unordered);
/**
* Returns the payload protocol Identifier.
*
* <P> A value indicating the type of payload protocol data being
* transmitted/received. This value is passed as opaque data by SCTP.
* {@code 0} indicates an unspecified payload protocol identifier.
*
* @return The Payload Protocol Identifier
*/
public abstract int payloadProtocolID();
/**
* Sets the payload protocol Identifier.
*
* <P> A value indicating the type of payload protocol data being
* transmitted. This value is passed as opaque data by SCTP.
*
* @param ppid
* The Payload Protocol Identifier, or {@code 0} indicate an
* unspecified payload protocol identifier.
*
* @return This MessageInfo
*
* @see MessageInfo#payloadProtocolID()
*/
public abstract MessageInfo payloadProtocolID(int ppid);
/**
* Returns the stream number that the message was received on, if the
* message has been received, otherwise the stream number that the message
* is to be sent on.
*
* @return The stream number
*/
public abstract int streamNumber();
/**
* Sets the stream number that the message is to be sent on.
*
* @param streamNumber
* The stream number
*
* @throws IllegalArgumentException
* If the streamNumber is negative or greater than {@code 65536}
*
* @return This MessageInfo
*/
public abstract MessageInfo streamNumber(int streamNumber);
/**
* The time period that the sending side may expire the message if it has
* not been sent, or {@code 0} to indicate that no timeout should occur. This
* value is only applicable for messages being sent, it has no meaning for
* received messages.
*
* @return The time period in milliseconds, or {@code 0}
*/
public abstract long timeToLive();
/**
* Sets the time period that the sending side may expire the message if it
* has not been sent.
*
* @param millis
* The time period in milliseconds, or {@code 0} to indicate that no
* timeout should occur
*
* @return This MessageInfo
*
* @see MessageInfo#timeToLive()
*/
public abstract MessageInfo timeToLive(long millis);
}