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This provides a set of diagramming notations that describe a business process. This notation is akin to UML activity diagram.

A way of letting your process rest in a known condition indefinitely.

A pause in the action that can only move forward when a known actor or agent in the system moves it forward.

An aggregation of states, activities, and other types of constructs that serializes them.

A concurrent execution of multiple threads of execution at the same time, originating from a common thread.

Each department may have its own task list to complete in order to achieve the goals of the overarching process.

A decision describes a node that is conditional, based on some logic that you inject.

To use PostgreSQL, you need to add a the driver library to the classpath.

<dependency> <groupId>org.jbpm.jbpm4</groupId> <artifactId>jbpm-jpdl</artifactId> <version>4.3</version> </dependency> Dependency for JBPM 4.

JBPM supports databases such as:-

To make use of jBPM from within a Spring application context.

To use jBPM as a stand-alone process server:-

It’s not too difficult to get jBPM working on JBoss EJB environment.

JBoss itself supports deploying processes to a directory and loading those, with some configuration.

jBPM is, fundamentally, a runtime that stores its state and jobs in a database. It uses:-

To have an annotated class be registered as a Hibernate entity, it needs to be registered with the:-

Because our jBPM configuration uses Hibernate, we have to configure the :-

The next bean—the dataSource—is configured entirely at your discretion. The properties are set using properties in the properties file :-

When we’re integrating with Spring, we modify the transaction-context element and the command-service element.

The hibernate-session element tells jBPM to reuse an existing Hibernate session:-

The spring-transaction-interceptor element is a special element to enable jBPM to defer to the TransactionManager defined in our application context.

jBPM will expose beans using the:-

jBPM, and indeed most workflow engines, passivate state for you, allowing a process to wait on external events :-

The method annotated with @PostConstruct will be run after the bean’s been configured to let the user inject custom initialization logic.

The business process file’s name needs to end in :-

At the top, we’ve injected some dependencies:

The class(CustomerServiceImpl) provides a few salient methods:- package com.apress.springrecipes.jbpm.jbpm4.customers; public interface CustomerService { void sendWelcomeEmail(Long customerId); void deauthorizeCustomer(Long customerId); void authorizeCustomer(Long customerId); Customer getCustomerById(Long customerId); Customer createCustomer(String email, String password, String firstName,  String lastName); void sendCustomerVerificationEmail(Long customerId); }

In the bean, setupProcessDefinitions is run when the bean is created.

Process definition will reference Spring beans using the JBoss expression language.

In jBPM, a business process is built using jPDL.

.In the customerService bean, a client will use createCustomer to create a customer record. <?xml version="1.0" encoding="UTF-8"?> <process name="RegisterCustomer" xmlns="http://jbpm.org/4.0/jpdl"> <start> <transition to="send-verification-email" /> </start> <java name="send-verification-email" expr="#{customerService}" method="sendCustomerVerificationEmail"> <arg> <object expr="#{customerId}" /> </arg> <transition to="confirm-receipt-of-verification-email" /> </java> <state name="confirm-receipt-of-verification-email"> <transition to="send-welcome-email" /> </state> <java name="send-welcome-email" expr="#{customerService}" method="sendWelcomeEmail"> <arg> <object expr="#{customerId}" /> </arg> </java> </process>

Inside the createCustomer method, we use jBPM to start the business process to track the Customer. This is done with the :- <?xml version="1.0" encoding="UTF-8"?> <process name="RegisterCustomer" xmlns="http://jbpm.org/4.0/jpdl"> <start> <transition to="send-verification-email" /> </start> <java name="send-verification-email" expr="#{customerService}" method="sendCustomerVerificationEmail"> <arg> <object expr="#{customerId}" /> </arg> <transition to="confirm-receipt-of-verification-email" /> </java> <state name="confirm-receipt-of-verification-email"> <transition to="send-welcome-email" /> </state> <java name="send-welcome-email" expr="#{customerService}" method="sendWelcomeEmail"> <arg> <object expr="#{customerId}" /> </arg> </java> </process>

Once in the java element named send-verification-email, jBPM will invoke the method:-

Inside authorizeCustomer, the service queries the server for the any processes waiting at the:-

The authorizeCustomer method also updates the Customer entity, marking it as authorized. From there, execution proceeds to the send-welcome-email java element.

OSGi—which was formerly known as the:-

OSGi provides a layer on top of the JVM’s default class loader.

On top of Spring Dynamic Modules, SpringSource built SpringSource dm Server, which is a server wired from top to bottom with OSGi and Spring.

OSGi is a framework.

User component models are:-

In OSGi, anything used by something else is a state.

“Service” doesn’t imply any:-

OSGi bundles are simply standard .jar files with customized MANIFESTs that OSGi consumes at runtime.

Tool which dynamically interrogates classes for their imports and generates OSGi–compliant entries.

The plug-in produces OSGi–compliant bundles that work in any container.

The Bundle-Activator directive describes to the OSGi environment, which class implements :-

When the bundle begins to load and start, it calls the start method of the:-

To start using Spring to smooth over some of the minutiae of resource acquisition and to help build more reliable systems in an OSGi environment.

Spring Dynamic Modules scans our deployed bundles and loads an ApplicationContext (actually, the specific type of the ApplicationContext is OsgiBundleXmlApplicationContext) into memory based on an event, or a trigger.

You’ll split your OSGi–specific Spring configuration and your plain-vanilla Spring configuration into:-