Public API of the Activiti engine.
Typical usage of the API starts by the creation of a {@link org.activiti.Configuration}
(typically based on a configuration file), from which a {@link org.activiti.ProcessEngine} can be obtained.
Through the services obtained from such a {@link org.activiti.ProcessEngine}, BPM and workflow operation
can be executed:
{@link org.activiti.ProcessService}: Allows the creation of {@link org.activiti.Deployment}s and the
starting of and searching on {@link org.activiti.ProcessInstance}s
{@link org.activiti.TaskService}: Exposes operations to manage human (standalone) {@link org.activiti.Task}s,
such as claiming, completing and assigning tasks
{@link org.activiti.IdentityService}: Used for managing {@link org.activiti.identity.User}s,
{@link org.activiti.identity.Group}s and the relations between them
{@link org.activiti.ManagementService}: Exposes engine admin and maintenance operations,
which have no relation to the runtime exection of business processes