io.pkts.streams

Enum SipStream.CallState

java.lang.Object

java.lang.Enum<SipStream.CallState>

io.pkts.streams.SipStream.CallState

All Implemented Interfaces:

Serializable, Comparable<SipStream.CallState>

Enclosing interface:

SipStream

public static enum SipStream.CallState
extends Enum<SipStream.CallState>

Even though SIP can be used for so much more than just establishing "phone calls" (VoIP) it is commonly used for this very purpose. As such, it seems useful to provide some kind of "call state" from a phone call perspective in the same way that wireshark does. Hence, this enum is used for exactly that and only has a meaning for INVITE dialogs. Note, RFC 4235 (an invite-initiated dialog event package) describes a similar state machine and this one here is similar but slightly different since we want to make it a little more high-level ala wireshark. Perhaps the wrong decision? Comments???

Enum Constant Summary

Enum Constants

Enum Constant and Description
CANCELLED If the call was cancelled you will end up in this state.
CANCELLING If we receive a CANCEL request then we move over to the canceling state.
COMPLETED Completed always means that the call was first successfully established and then completed at some point.
FAILED The call failed.
IN_CALL If a 2xx response is generated for the INVITE request, then the call-state progresses to the "in call" state.
INITIAL We have only seen an INVITE request and nothing else.
REDIRECT The INVITE request was redirected (3xx responses)
REJECTED The INVITE request was rejected (4xx and 6xx responses) for some reason.
RINGING If we receive a 180/183, the state will progress to the ringing state.
START Just to have an initial state when everything is created (and since I decided to call the first "real" state for INITIAL I couldn't use INIT or similar since it would be confusing)
TRYING If we receive a 100 Trying response, the call-state will transition over to the trying state.
UNKNOWN Sorry, couldn't figure it out! Examine the call flow and let me know which state you believe the call should be in.

Method Summary

Modifier and Type	Method and Description
static SipStream.CallState	valueOf(String name) Returns the enum constant of this type with the specified name.
static SipStream.CallState[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

START

public static final SipStream.CallState START

Just to have an initial state when everything is created (and since I decided to call the first "real" state for INITIAL I couldn't use INIT or similar since it would be confusing)

INITIAL

public static final SipStream.CallState INITIAL

We have only seen an INVITE request and nothing else. Hence, the call state is currently in the initial phase.

TRYING

public static final SipStream.CallState TRYING

If we receive a 100 Trying response, the call-state will transition over to the trying state.

RINGING

public static final SipStream.CallState RINGING

If we receive a 180/183, the state will progress to the ringing state.

CANCELLING

public static final SipStream.CallState CANCELLING

If we receive a CANCEL request then we move over to the canceling state. However, we may actually move back to in call because as always there is a race condition around canceling.

REDIRECT

public static final SipStream.CallState REDIRECT

The INVITE request was redirected (3xx responses)

IN_CALL

public static final SipStream.CallState IN_CALL

If a 2xx response is generated for the INVITE request, then the call-state progresses to the "in call" state. Note, technically we must really wait for the ACK but there are a lof of real-world clients that will start sending media (RTP) as soon as the 2xx is sent and from their perspective the call has been established. However, if the 3-way handshake fails the state will progress over to FAILED. Hence, if you examine the states the call has been and you see a transition from IN_CALL to FAILED then you can be 100% sure that there is some kind of NAT/FW issue going on. Typically, either the UA:s stamped the wrong information in the Contact-header or there is a firewall closing a little too fast.

CANCELLED

public static final SipStream.CallState CANCELLED

If the call was cancelled you will end up in this state.

COMPLETED

public static final SipStream.CallState COMPLETED

Completed always means that the call was first successfully established and then completed at some point. Note, there are a lot of corner cases where e.g. the BYE wouldn't make it through etc but this is still marked as completed.

REJECTED

public static final SipStream.CallState REJECTED

The INVITE request was rejected (4xx and 6xx responses) for some reason.

FAILED

public static final SipStream.CallState FAILED

The call failed. The most typical scenario is receiving 5xx responses but if we e.g. get a 408, 481 we will also mark the call as failed. Only if we get these on the initial INVITE though. Also, this can happen during the initial 3-way handshake where the 200 OK doesn't make it back to the UAC or the UAS doesn't get the ACK so both of them keeps re-transmitting (depending where the error is of course. Typically, the 200 OK will make it through but the ACK will no so you will see a lot of re-transmission of the 200 as well as the ACK but the ACK will not reach the UAS)

UNKNOWN

public static final SipStream.CallState UNKNOWN

Sorry, couldn't figure it out! Examine the call flow and let me know which state you believe the call should be in.

Method Detail

values

public static SipStream.CallState[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (SipStream.CallState c : SipStream.CallState.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static SipStream.CallState valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null