1. A brief introduction to Activiti
Activiti is a light-weight workflow and Business Process Management (BPM) Platform targeted at business people, developers and system admins. Its core is a super-fast and rock-solid BPMN 2 process engine for Java. It's open-source and distributed under the Apache license. Activiti runs in any Java application, on a server, on a cluster or in the cloud. It integrates perfectly with Spring, it is extremely lightweight and based on simple concepts.
This Activiti is not an Android Activity . Activity is the most basic and most commonly used four components in Android components ( Activity , Service service, Content Provider content provider
As an Apache-licensed open source platform for workflow and business process management, Activiti's core is a Java-based ultra-fast and ultra-stable BPMN 2.0 process engine, emphasizing the embeddability and extensibility of process services, and more emphasis on business-oriented personnel.
At its core, Activiti is a BPMN 2.0 process engine. BPMN is a BPM standard that is widely accepted by various BPM manufacturers. The full name is Business Process Model and Notation. It is maintained by the OMG organization. Compared with the first version, the most important change of BPMN 2.0 is that it defines the meta-model and execution semantics of the process, that is, it solves the problems of storage, exchange and execution by itself. This means that the BPMN 2.0 process definition model can not only be executed in any BPMN 2.0 compliant engine, but can also be exchanged between graphical editors. As a standard, BPMN 2.0 unifies the workflow community.
Activiti is a project created by jBPM creator Tom Baeyens after he left JBoss and builds on years of experience developing jBPM versions 1 through 4 to create the next generation of BPM solutions. At the same time, Activiti chose the Apache license. On the one hand, it hopes that Activiti can have a longer life, because it is not controlled by any individual or company but belongs to the entire community. On the other hand, it is hoped that this loose license will allow Activiti BPM The engine and BPMN 2.0 are more widely adopted, used and commercialized.
For Java developers, Tom Baeyens, chief architect of Activiti, mentioned that the first goal of Activiti is to win the favor of developers. First of all, it is very convenient to use. It is just a jar file. You only need to put it in the classpath when using it. Of course, Activiti can also be used as a standalone server. At the same time, Activiti provides many advanced BPM tools, including development Collaboration tools have been developed to enable developers, business personnel, and operation and maintenance personnel to work better together.
Introduction to the functions of the Activiti service
RepositoryService: The definition of each different version of the business process in Activiti needs to use some definition files, deployment files and supporting data (such as BPMN2.0 XML files, form definition files, process definition image files, etc.), these files are stored in Activiti Built-in Repository. Repository Service provides access to the repository.
RuntimeService: In Activiti, every time a process definition is started, a corresponding process object instance will be generated. Runtime Service provides functions such as starting a process, querying process instances, and setting and obtaining process instance variables. In addition, it provides access to process deployment, process definitions and process instances.
TaskService: Each execution node in the business process definition in Activiti is called a Task, and operations such as data access and state changes in the process need to be completed in the Task. Task Service provides operations related to user Task and Form. It provides functions such as runtime task query, collection, completion, deletion, and variable setting.
IdentityService: Activiti has built-in user and group management functions, and the information of these users and groups must be used to obtain the corresponding Task. Identity Service provides management of users and groups in the Activiti system.
ManagementService: Management Service provides management and maintenance functions for the Activiti process engine, which are not used in workflow-driven applications and are mainly used for routine maintenance of the Activiti system.
HistoryService: History Service is used to obtain information about running or completed process instances. Different from the process information obtained in Runtime Service, history information contains persistent information that has been persisted and has been optimized for queries.
FormService: Processes and status tasks in Activiti can be associated with business-related data. By using the Form Service, you can access the form data needed to initiate and complete tasks and render the form as needed.