Below is few question Dump for R3 Corda 4 Developer Certification
81) How does the receiver Node download the physical attachments from the sender Node?
Answer : Download the physical files via RPC client calls
82) Attachment metadata can be queried in a similar way to the vault.
Answer : TRUE
83) What service does an Oracle provide to a Corda Network?
Answer : Provides data external to the ledger into a Transaction and signs the Transaction.
84) Oracle services can be used both when proposing and when verifying transactions.
Answer : TRUE
85) How can a contract ensure that a transaction is only valid if it is fully signed before time X?
Answer : By adding a TimeWindow to the Transaction and getting the Notary to sign the Transaction within that TimeWindow.
86) Where is the default transaction size stored at?
Answer : Network Parameter file
87) If a bilateral flow is kicked off between two parties, first checkpointed by Party A and then by Party B, do those flows share an Id? e.g. – if I search through the checkpoints on both nodes, will I be able to match them?
Answer : No, The id of the checkpoint is based on the id of the FlowStateMachine. This state machine is not shared between the two nodes
88) What are the key storetypes that Corda accept? (Multi-select)
Answer : Pkcs12, Jks
89) Assuming you are upgrading your node from the older version to the latest version of Corda, what is the first command that you are running?
Answer : gracefulShutdown
90) What is the possible return type of this method? ______________ output = stx.getTx().getOutputs().get(0).getData();
Answer : ContractState
91) How does testing code work in the test folder?
Answer : It will start a mock network and run the unit tests to test out the different parts of the application
92) What does the following code return? val confidentialIdentities = subFlow(SwapIdentitiesFlow( counterpartySession, GENERATE_CONFIDENTIAL_IDS.childProgressTracker()))
Answer : A LinkedHashMap of <Party, AnonymousParty> pair
93) When distributing states to the observer manually using helper flow, which method actually handles the writing to the ledger?
Answer : recordTransaction