com.r3corda.core.contracts.clauses / SingleVerify / verify

# verify

`abstract fun verify(tx: TransactionForContract, commands: Collection<AuthenticatedObject<CommandData>>): Set<CommandData>`

Verify the transaction matches the conditions from this clause. For example, a "no zero amount output" clause would check each of the output states that it applies to, looking for a zero amount, and throw IllegalStateException if any matched.

Return
the set of commands that are consumed IF this clause is matched, and cannot be used to match a later clause. This would normally be all commands matching "requiredCommands" for this clause, but some verify() functions may do further filtering on possible matches, and return a subset. This may also include commands that were not required (for example the Exit command for fungible assets is optional).