com.r3corda.protocols / TwoPartyDealProtocol / Secondary

# Secondary

`abstract class Secondary<U> : ProtocolLogic<SignedTransaction>`

Abstracted bilateral deal protocol participant that is recipient of initial communication.

Theres a good chance we can push at least some of this logic down into core protocol logic and helper methods etc.

### Types

RECEIVING | `object RECEIVING : Step`
RECORDING | `object RECORDING : Step`
SIGNING | `object SIGNING : Step`
SWAPPING_SIGNATURES | `object SWAPPING_SIGNATURES : Step`
VERIFYING | `object VERIFYING : Step`

### Constructors

<init> | `Secondary(progressTracker: ProgressTracker = Secondary.tracker())` Abstracted bilateral deal protocol participant that is recipient of initial communication.

### Properties

otherSide | `abstract val otherSide: Party`
progressTracker | `open val progressTracker: ProgressTracker` Override this to provide a ProgressTracker. If one is provided and stepped, the framework will do something helpful with the progress reports. If this protocol is invoked as a sub-protocol of another, then the tracker will be made a child of the current step in the parent. If its null, this protocol doesnt track progress.
sessionID | `abstract val sessionID: Long`
topic | `open val topic: String` The topic to use when communicating with other parties. If more than one topic is required then use sub-protocols. Note that this is temporary until protocol sessions are properly implemented.

### Inherited Properties

logger | `val logger: <ERROR CLASS>` This is where you should log things to.
psm | `lateinit var psm: ProtocolStateMachine<*>` Reference to the Fiber instance that is the top level controller for the entire flow.
serviceHub | `val serviceHub: ServiceHub` Provides access to big, heavy classes that may be reconstructed from time to time, e.g. across restarts. It is only available once the protocol has started, which means it cannnot be accessed in the constructor. Either access this lazily or from inside call.

### Functions

assembleSharedTX | `abstract fun assembleSharedTX(handshake: Handshake<U>): <ERROR CLASS><TransactionBuilder, List<PublicKey>>`
call | `open fun call(): SignedTransaction` This is where you fill out your business logic.
validateHandshake | `abstract fun validateHandshake(handshake: Handshake<U>): Handshake<U>`

### Inherited Functions

receive | `fun <T : Any> receive(sessionIDForReceive: Long): UntrustworthyData<T>` `fun <T : Any> receive(sessionIDForReceive: Long, receiveType: Class<T>): UntrustworthyData<T>`
send | `fun send(destination: Party, sessionID: Long, payload: Any): Unit`
sendAndReceive | `fun <T : Any> sendAndReceive(destination: Party, sessionIDForSend: Long, sessionIDForReceive: Long, payload: Any): UntrustworthyData<T>`
subProtocol | `fun <R> subProtocol(subLogic: ProtocolLogic<R>): R` Invokes the given subprotocol by simply passing through this ProtocolLogics reference to the ProtocolStateMachine and then calling the call method.

### Companion Object Functions

tracker | `fun tracker(): ProgressTracker`

### Inheritors

Acceptor | `class Acceptor<T : DealState> : Secondary<T>` One side of the protocol for inserting a pre-agreed deal.
Fixer | `class Fixer : Secondary<StateRef>` One side of the fixing protocol for an interest rate swap, but could easily be generalised further.