javax.sip
Class TransactionState

java.lang.Object
  javax.sip.TransactionState

All Implemented Interfaces:

java.io.Serializable

public final class TransactionState
extends java.lang.Object
implements java.io.Serializable

This class contains the enumerations that define the underlying state of an existing transaction. SIP defines four types of transactions, these are Invite Client transactions, Invite Server transactions, Non-Invite Client transactions and Non-Invite Server transactions. There are six explicit states for the various transactions, namely:

• Calling:
  • Invite Client transaction: The initial state, "calling", MUST be entered when the application initiates a new client transaction with an INVITE request.
• Trying:
  • Non-Invite Client transaction: The initial state "Trying" is entered when the application initiates a new client transaction with a request.
  • Non-Invite Server transaction: The initial state "Trying" is entered when the application is passed a request other than INVITE or ACK.
• Proceeding:
  • Invite Client transaction: If the client transaction receives a provisional response while in the "Calling" state, it transitions to the "Proceeding" state.
  • Non-Invite Client transaction: If a provisional response is received while in the "Trying" state, the client transaction SHOULD move to the "Proceeding" state.
  • Invite Server transaction: When a server transaction is constructed for a request, it enters the initial state "Proceeding".
  • Non-Invite Server transaction: While in the "Trying" state, if the application passes a provisional response to the server transaction, the server transaction MUST enter the "Proceeding" state.
• Completed: The "Completed" state exists to buffer any additional response retransmissions that may be received, which is why the client transaction remains there only for unreliable transports.
  • Invite Client transaction: When in either the "Calling" or "Proceeding" states, reception of a response with status code from 300-699 MUST cause the client transaction to transition to "Completed".
  • Non-Invite Client transaction: If a final response (status codes 200-699) is received while in the "Trying" or "Proceeding" state, the client transaction MUST transition to the "Completed" state.
  • Invite Server transaction: While in the "Proceeding" state, if the application passes a response with status code from 300 to 699 to the server transaction, the state machine MUST enter the "Completed" state.
  • Non-Invite Server transaction: If the application passes a final response (status codes 200-699) to the server while in the "Proceeding" state, the transaction MUST enter the "Completed" state.
• Confirmed: The purpose of the "Confirmed" state is to absorb any additional ACK messages that arrive, triggered from retransmissions of the final response. Once this time expires the server MUST transition to the "Terminated" state.
  • Invite Server transaction: If an ACK is received while the server transaction is in the "Completed" state, the server transaction MUST transition to the "Confirmed" state.
• Terminated: The transaction MUST be available for garbage collection the instant it enters the "Terminated" state.
  • Invite Client transaction: When in either the "Calling" or "Proceeding" states, reception of a 2xx response MUST cause the client transaction to enter the "Terminated" state. If amount of time that the server transaction can remain in the "Completed" state when unreliable transports are used expires while the client transaction is in the "Completed" state, the client transaction MUST move to the "Terminated" state.
  • Non-Invite Client transaction: If the transaction times out while the client transaction is still in the "Trying" or "Proceeding" state, the client transaction SHOULD inform the application about the timeout, and then it SHOULD enter the "Terminated" state. If the response retransmissions buffer expires while in the "Completed" state, the client transaction MUST transition to the "Terminated" state.
  • Invite Server transaction: If in the "Proceeding" state, and the application passes a 2xx response to the server transaction, the server transaction MUST transition to the "Terminated" state. When the server transaction abandons retransmitting the response while in the "Completed" state, it implies that the ACK was never received. In this case, the server transaction MUST transition to the "Terminated" state, and MUST indicate to the TU that a transaction failure has occurred.
  • Non-Invite Server transaction: If the request retransmissions buffer expires while in the "Completed" state, the server transaction MUST transition to the "Terminated" state.

For each specific transaction state machine, refer to RFC3261.

Author:

BEA Systems, NIST

See Also:

Serialized Form

Field Summary

static int	_CALLING This constant value indicates the internal value of the "Calling" constant.
static int	_COMPLETED This constant value indicates the internal value of the "Completed" constant.
static int	_CONFIRMED This constant value indicates the internal value of the "Confirmed" constant.
static int	_PROCEEDING This constant value indicates the internal value of the "Proceeding" constant.
static int	_TERMINATED This constant value indicates the internal value of the "Terminated" constant.
static int	_TRYING This constant value indicates the internal value of the "Trying" constant.
static TransactionState	CALLING This constant value indicates that the transaction state is "Calling".
static TransactionState	COMPLETED This constant value indicates that the transaction state is "Completed".
static TransactionState	CONFIRMED This constant value indicates that the transaction state is "Confirmed".
static TransactionState	PROCEEDING This constant value indicates that the transaction state is "Proceeding".
static TransactionState	TERMINATED This constant value indicates that the transaction state is "Terminated".
static TransactionState	TRYING This constant value indicates that the transaction state is "Trying".

Method Summary

boolean	equals(java.lang.Object obj) Compare this transaction state for equality with another.
static TransactionState	getObject(int transactionState) This method returns the object value of the TransactionState
int	getValue() This method returns the integer value of the TransactionState
int	hashCode() Get a hash code value for this transaction state.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

_CALLING

public static final int _CALLING

This constant value indicates the internal value of the "Calling" constant.
This constant has an integer value of 0.

See Also:

Constant Field Values

CALLING

public static final TransactionState CALLING

This constant value indicates that the transaction state is "Calling".

_TRYING

public static final int _TRYING

This constant value indicates the internal value of the "Trying" constant. This constant has an integer value of 1.

See Also:

Constant Field Values

TRYING

public static final TransactionState TRYING

This constant value indicates that the transaction state is "Trying".

_PROCEEDING

public static final int _PROCEEDING

This constant value indicates the internal value of the "Proceeding" constant.
This constant has an integer value of 2.

See Also:

Constant Field Values

PROCEEDING

public static final TransactionState PROCEEDING

This constant value indicates that the transaction state is "Proceeding".

_COMPLETED

public static final int _COMPLETED

This constant value indicates the internal value of the "Completed" constant.
This constant has an integer value of 3.

See Also:

Constant Field Values

COMPLETED

public static final TransactionState COMPLETED

This constant value indicates that the transaction state is "Completed".

_CONFIRMED

public static final int _CONFIRMED

This constant value indicates the internal value of the "Confirmed" constant.
This constant has an integer value of 4.

See Also:

Constant Field Values

CONFIRMED

public static final TransactionState CONFIRMED

This constant value indicates that the transaction state is "Confirmed".

_TERMINATED

public static final int _TERMINATED

This constant value indicates the internal value of the "Terminated" constant.
This constant has an integer value of 5.

See Also:

Constant Field Values

TERMINATED

public static final TransactionState TERMINATED

This constant value indicates that the transaction state is "Terminated".

Method Detail

getObject

public static TransactionState getObject(int transactionState)

This method returns the object value of the TransactionState

Parameters:

transactionState - The integer value of the TransactionState

Returns:

The TransactionState Object

getValue

public int getValue()

This method returns the integer value of the TransactionState

Returns:

The integer value of the TransactionState

equals

public boolean equals(java.lang.Object obj)

Compare this transaction state for equality with another.

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to compare this with.

Returns:

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

Since:

1.2

hashCode

public int hashCode()

Get a hash code value for this transaction state.

Overrides:

hashCode in class java.lang.Object

Returns:

a hash code value.

Since:

1.2

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object