org.camunda.bpm.engine.runtime

Interface MessageCorrelationBuilder

All Known Implementing Classes:

MessageCorrelationBuilderImpl

public interface MessageCorrelationBuilder

A fluent builder for defining message correlation

Author:

Daniel Meyer

Method Summary

Methods

Modifier and Type	Method and Description
void	correlate() Executes the message correlation.
void	correlateAll() Executes the message correlation for multiple messages.
void	correlateExclusively() Behaves like correlate(), however uses pessimistic locking for correlating a waiting execution, meaning that two threads correlating a message to the same execution in parallel do not end up continuing the process in parallel until the next wait state is reached
MessageCorrelationBuilder	processInstanceBusinessKey(String businessKey) Correlate the message such that the process instance has a business with the given name and value.
MessageCorrelationBuilder	processInstanceId(String id) Correlate the message such that a process instance with the given id is selected.
MessageCorrelationBuilder	processInstanceVariableEquals(String variableName, Object variableValue) Correlate the message such that the process instance has a variable with the given name and value.
MessageCorrelationBuilder	setVariable(String variableName, Object variableValue) Pass a variable to the execution waiting on the message.
MessageCorrelationBuilder	setVariables(Map<String,Object> variables) Pass a map of variables to the execution waiting on the message.

Method Detail

processInstanceBusinessKey

MessageCorrelationBuilder processInstanceBusinessKey(String businessKey)

Correlate the message such that the process instance has a business with the given name and value.

Parameters:

businessKey - the businessKey to correlate on.

Returns:

the builder

processInstanceVariableEquals

MessageCorrelationBuilder processInstanceVariableEquals(String variableName,
                                                      Object variableValue)

Correlate the message such that the process instance has a variable with the given name and value.

Parameters:

variableName - the name of the process instance variable to correlate on.

variableValue - the value of the process instance variable to correlate on.

Returns:

the builder

processInstanceId

MessageCorrelationBuilder processInstanceId(String id)

Correlate the message such that a process instance with the given id is selected.

Parameters:

id - the id of the process instance to correlate on.

Returns:

the builder

setVariable

MessageCorrelationBuilder setVariable(String variableName,
                                    Object variableValue)

Pass a variable to the execution waiting on the message. Use this method for passing the message's payload.

Invoking this method multiple times allows passing multiple variables.

Parameters:

variableName - the name of the variable to set

variableValue - the value of the variable to set

Returns:

the builder

setVariables

MessageCorrelationBuilder setVariables(Map<String,Object> variables)

Pass a map of variables to the execution waiting on the message. Use this method for passing the message's payload

Parameters:

variables - the map of variables

Returns:

the builder

correlate

void correlate()

Executes the message correlation.

This will result in either:

• Exactly one waiting execution is notified to continue. The notification is performed synchronously.
• Exactly one Process Instance is started in case the message name matches a message start event of a process. The instantiation is performed synchronously.
• MismatchingMessageCorrelationException is thrown. This means that either too many executions match the correlation or that no execution matches the correlation.

Throws:

MismatchingMessageCorrelationException - if none or more than one execution or process definition is matched by the correlation

AuthorizationException - if one execution is matched and the user has no Permissions.UPDATE permission on Resources.PROCESS_INSTANCE or no Permissions.UPDATE_INSTANCE permission on Resources.PROCESS_DEFINITION. if one process definition is matched and the user has no Permissions.CREATE permission on Resources.PROCESS_INSTANCE and no Permissions.CREATE_INSTANCE permission on Resources.PROCESS_DEFINITION.

correlateExclusively

void correlateExclusively()

Behaves like correlate(), however uses pessimistic locking for correlating a waiting execution, meaning that two threads correlating a message to the same execution in parallel do not end up continuing the process in parallel until the next wait state is reached

CAUTION: Wherever there are pessimistic locks, there is a potential for deadlocks to occur. This can either happen when multiple messages are correlated in parallel, but also with other race conditions such as a message boundary event on a user task. The process engine is not able to detect such a potential. In consequence, the user of this API should investigate this potential in his/her use case and implement countermeasures if needed.

A less error-prone alternative to this method is to set appropriate async boundaries in the process model such that parallel message correlation is solved by optimistic locking.

correlateAll

void correlateAll()

Executes the message correlation for multiple messages.

This will result in any number of the following:

• Any number of waiting executions are notified to continue. The notification is performed synchronously.
• Zero or one Process Instance is started in case the message name matches a message start event of a process. The instantiation is performed synchronously.

Throws:

AuthorizationException - if at least one execution is matched and the user has no Permissions.UPDATE permission on Resources.PROCESS_INSTANCE or no Permissions.UPDATE_INSTANCE permission on Resources.PROCESS_DEFINITION. if one process definition is matched and the user has no Permissions.CREATE permission on Resources.PROCESS_INSTANCE and no Permissions.CREATE_INSTANCE permission on Resources.PROCESS_DEFINITION.