javax.sip.header

Interface CallIdHeader

All Superinterfaces:

Cloneable, Header, Serializable

All Known Implementing Classes:

CallID

public interface CallIdHeader
extends Header

The Call-ID header field uniquely identifies a particular invitation or all registrations of a particular client. A single multimedia conference can give rise to several calls with different Call-IDs, for example, if a user invites a single individual several times to the same (long-running) conference. Call-IDs are case-sensitive and are simply compared byte-by-byte.

Call-ID is generated by the combination of a random string and the softphone's host name or IP address. The combination of the To tag, From tag, and Call-ID completely defines a peer-to-peer SIP relationship between two users and is referred to as a dialog. It MUST be the same for all requests and responses sent by either User Agent in a dialog. It SHOULD be the same in each registration from a User Agent.

All SIP User Agents must have a means to guarantee that the Call-ID header fields they produce will not be inadvertently generated by any other User Agent. Note that when requests are retried after certain failure responses that solicit an amendment to a request (for example, a challenge for authentication), these retried requests are not considered new requests, and therefore do not need new Call-ID header fields.

Use of cryptographically random identifiers in the generation of Call-IDs is RECOMMENDED. Implementations MAY use the form "localid@host".

For Example:
Call-ID: [email protected]

Version:

1.2

Author:

BEA Systems, NIST

Field Summary

Fields

Modifier and Type	Field and Description
static String	NAME Name of CallIdHeader

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object obj) Compare this CallIdHeader for equality with another.
String	getCallId() Returns the Call-Id of CallIdHeader.
void	setCallId(String callId) Sets the Call-Id of the CallIdHeader.

Methods inherited from interface javax.sip.header.Header

clone, getName, hashCode, toString

Field Detail

NAME

static final String NAME

Name of CallIdHeader

See Also:

Constant Field Values

Method Detail

setCallId

void setCallId(String callId)
               throws ParseException

Sets the Call-Id of the CallIdHeader. The CallId parameter uniquely identifies a serious of messages within a dialogue.

Parameters:

callId - - the string value of the Call-Id of this CallIdHeader.

Throws:

ParseException - which signals that an error has been reached unexpectedly while parsing the callId value.

getCallId

String getCallId()

Returns the Call-Id of CallIdHeader. The CallId parameter uniquely identifies a series of messages within a dialogue.

Returns:

the String value of the Call-Id of this CallIdHeader

equals

boolean equals(Object obj)

Compare this CallIdHeader for equality with another. This method overrides the equals method in javax.sip.Header. This method specifies object equality as outlined by RFC3261. Call-IDs are case-sensitive and are simply compared byte-by-byte.

Specified by:

equals in interface Header

Overrides:

equals in class Object

Parameters:

obj - the object to compare this CallIdHeader with.

Returns:

true if obj is an instance of this class representing the same CallIdHeader as this, false otherwise.

Since:

v1.2