com.r3corda.core.contracts / kotlin.collections.Collection

### Extensions for kotlin.collections.Collection

requireSingleCommand | `fun <T : CommandData> Collection<AuthenticatedObject<CommandData>>.requireSingleCommand(): <ERROR CLASS>` `fun <C : CommandData> Collection<AuthenticatedObject<CommandData>>.requireSingleCommand(klass: Class<C>): <ERROR CLASS>`
select | `fun <T : CommandData> Collection<AuthenticatedObject<CommandData>>.select(signer: PublicKey? = null, party: Party? = null): <ERROR CLASS>` Filters the command list by type, party and public key all at once. `fun <T : CommandData> Collection<AuthenticatedObject<CommandData>>.select(signers: Collection<PublicKey>?, parties: Collection<Party>?): <ERROR CLASS>` Filters the command list by type, parties and public keys all at once.