Contract
A contract state (or just "state") contains opaque data used by a contract program. It can be thought of as a disk file that the program can use to persist data across transactions. States are immutable: once created they are never updated, instead, any changes must generate a new successor state. States can be updated (consumed) only once: the notary is responsible for ensuring there is no "double spending" by only signing a transaction if the input states are all free.
Inheritors
Properties
A participant is any party that should be notified when the state is created or consumed.
Obtain the typename of the required ContractClass associated with the target ContractState, using the BelongsToContract annotation by default, but falling through to checking the state's enclosing class if there is one and it inherits from Contract.