JBoss jbpm is a flexible and scalable workflow management system. JBoss jbpm has a set of intuitive process modeling languages. This language can be used with tasks, waiting states for asynchronous communication (wait state), timers, and automated actions) and other graphical representation of business processes. By integrating these operations, JBoss jbpm has a powerful and Scalable Control Process mechanism. JBoss jbpm has a small degree of external dependency. You can use JBoss as if you were using a Java class library. It can also be deployed on a high-performance J2EE cluster application server. JBoss jbpm can be configured to run on any database and deployed on any application server.
Process Modeling Language jpdlJbpm Process Definition Language (jpdl) is a chart-oriented process modeling language used by jbpm. Is a specific domain language (DSL ). It is an extension of the XML processing Description Language (xpdl) language proposed by WfMC (Workflow Management Alliance) and adds some jbpm elements. It features several state nodes. 1. State wait status. In this status, the execution of the entire business program instance will be interrupted. The execution of the business program instance can continue until the external participants initiate the command to continue the execution. 2. node status. This state is opposite to the State. When the business program instance runs on this node, the execution will not stop. But will continue to execute. If the node exists, there are multiple departure directions. Then, the first exit direction will be executed. In the node status, external participants are not required. This part of the business process is automatically and instantly completed. 3. Deploy determines the status. Like node, deploy is in real-time state, rather than waiting state. The conditions can be set in the transition of demo-'s multiple departures. When the business program instance is in the deactivating state, all the exit and turn conditions are calculated in sequence. When the condition is true, the turn is immediately executed. If no condition is set for the redirection, the condition value for this redirection is true. Demo-e is the most powerful instant state. 4. Task node. Like the state, tasknode is in the waiting state. Tasknode is the most powerful waiting state. Jbpm provides a powerful support mechanism for tasknode. Therefore, we strongly recommend that you use tasknode to process the waiting state! Task nodes can have multiple task tasks. A task is a waiting state that is handled by external participants. The task must be completed by external participants. By default, After all task instances of a task node are completed, the execution of the business program instance can continue. However, you can also set to never continue, or immediately continue execution. Or execute the task after the first task is completed. You can also specify which one to switch to transition when the external participant ends the task instance to continue the process. In addition to task nodes, the start-state node can also contain tasks. However, it can only contain one task. The purpose of this task is to allow the business program instance initiator to create managed resources and other tasks. I have never seen a web development technology in the Web management application provided by jbpm. It provides a powerful function for managing business program instances, especially tasks. As long as the start-state defined by a business program contains the task definition, you can create an instance defined by this business program in the web program. The web program can also automatically create a form for the corresponding task instance variables and the corresponding exit button according to the definition of the business program. Although this web application is very powerful, it uses a non-mainstream technology that I am not familiar. Therefore, in your own applications, it is best to write your own front-end presentation layer instead of using its technology.
Jbpm Construction TechnologyJbpm is a business program management engine and a workflow engine. It supports jpdl. It also provides support for BPEL. I have not studied jbpm's support for BPEL. As a workflow engine, you must process the "Wait state ". Jbpm integrates the hibernate technology to process databases. It creates a series of database tables and persists the "waiting state" required by the workflow engine ". Therefore, jbpm supports all databases supported by hibernate. Jbpm can also persistently store Java objects in the database. It can save the Java class objects supported by hibernate to the database and persistently store the class objects that implement the serializable interface to the database! The specific implementation mechanism is unknown! In addition, jbpm uses the IOC container JBoss Seam. JBoss Seam is very similar to spring and can manage Java class objects. I have not studied JBoss Seam.
Current work and future researchAt present, I have a lot of knowledge about jpdl, but research on complex task management and authentication management is not enough. 1. You need to find out how to use struts to develop a set of pages for obtaining the user task list. 2. Identity management is required for task management. Jbpm provides a set of identity management mechanisms. However, we obviously cannot manage the application identity to the identity management module of jbpm for maintenance. We need to remove the jbpm identity management module and integrate the jbpm tasks with the identity database of our own applications. 3. jpdl is suitable for Java. It is suitable for WebServices. We need to study the support of jbpm for BPEL. 4. The JBoss Seam container is widely used in jbpm and must be understood.
