Handling process variables

When modeling a process, it may be necessary to check the value of a variable (RC variables are the most obvious example) or to access the values of a variable if it is not a simple string but a complex type with methods (e.g. the FileDetail variable type when activating an instance with the NewFile trigger).

Process variables are persistent entities that live within each process instance, identified by a name and a value.

Each time a process instance is started, the variables required to create the contract are activated and assigned their value. Any variables declared in each service task are activated during execution when that particular service task is encountered and executed without error.

The way to get the value of a simple variable is to enclose it in ${variableName}. If it is a complex variable like the one described in Process Variable Objects below, it will contain multiple values that can be accessed with its getter method: e.g. ${file.getRegistryId()}.

If the value of a variable is to be checked, in the case of an exclusive gateway, the condition must be between brackets: ${variableValue == 0} or [${file.getRegistryId() == 12}].

All variable names are in the same "bucket" as the entire flow instance. So, any service task writing a variable named "RC" will overwrite the previous one having the same name. To avoid undesired overwrites, use UNIQUE variable names in the same process model.

When testing a process variable value in a conditional execution, keep in mind all possible scenarios when implementing the condition. If you design a conditional flow with something like: ${variableValue.equals("go here")}, you are actually assuming that the variable exists and that it is not null. Any condition should consider first of all that a variable exists, then that it is not null, and then if it has or is not a specific value. A statement like this: ${execution.getVariable("variableValue") != null && variableValue != null && variableValue.equals("go here")} will verify that variableValue exists, that its value is not null, and that it has a value that matches the "go here" string.

Process Variable Objects

These are variables of type "Object" that can be found in a process instance. The user modeling a process won't be able to access a variable value just by its name, that is what happens with non-object variables:

${myCustomVariable}

but since those are objects, there are methods providing access to the object's internal desired value:

i.e. ${myCustomVariable.getVariableValue()}

FileDetail

FileDetail is a Java Object returned from the New File Event and available as a predefined variable --> file.

Parameter	Type	Function to retrieve the result	Description
registryId	Long	getRegistryId()	The Id Fileset inserted in the Databox (ex: ${file.getRegistryId()})
clusterName	String	getClusterName()	The Cluster name where the file has been received (ex: ${file.getClusterName()})
virtualPath	String	getVirtualPath()	The Databox (Virtual Path) where the file has been inserted. The format is vfsName:vfsPath (ex: ${file.getVirtualPath()}) Sample value: epoLAB-vfs-unsigned:/eMail_attachment
name	String	getName()	The Original File Name (ex: ${file.getName()})
virtualFolder	String	getVirtualFolder()	The Databox Folder where the file has been inserted. The format is vfsPath (ex: ${file.getVirtualPath()}) Sample value: /eMail_attachment
virtualFs	String	getVirtualFS()	The Databox FileSystem name where the file has been inserted. The format is vfsName (ex: ${file.getVirtualFS()}) Sample value: epoLAB-vfs-unsigned
extension	String	getExtension()	File extension
nameNoExtension	String	getNameNoExtension()	File name without extension
absoluteFileName	String	getAbsoluteFileName()	The absolute file name of the file (ex: ${file.getAbsoluteFileName()})
metadata	String	getMetadataValue(String key)	Get a file metadata value by key
metadata	List <String>	getMetadatakeys()	Get file metadata values (list of values) NOTE: available only when the ${file} variable is created by an Incoming Update Metadata Event.

ExternalFile

ExternalFile is a Java object returned by service tasks of the following types: Spls, DataboxSpls, RemoteSpls, and VirtualBox LS. Each service task returns a variable --> fileList that is a List. In the following examples, we assume that the current element of the list is referenced as --> currentFile.

Parameter	Type	Function to retrieve the result	Description
fileId	Long	getFileId()	The Id Fileset inserted in the Databox (ex: ${currentFile.getFileId()}). This is available only from DataboxSpls that lists files in a Databox, otherwise is NULL
size	Long	getSize()	The size file attribute provided by the subsystem that created this entry
dateModified	Date	getDatemodified()	The date of the last file modification
directory	Boolean	getDirectory()	If true the file is a Directory (ex: ${currentFile.getDirectory()})
filePath	String	getFilePath()	The full path of the file (ex: ${currentFile .getFilePath()})
fileName	String	getFileName()	File Name (ex: ${currentFile.getFileName()})
fileNameNoExtension	String	getFileNameNoExtension()	File Name only without extension (ex: ${currentFile.getFileNameNoExtension()})
size	Long	getSize()	The size of the file (ex: ${currentFile.getFileSize()})

Properties

Properties is a Java Object returned from Command Server service tasks: Spprop. The return variable is --> property and is a Map<String, String> read from a property file.

Parameter	Type	Function to retrieve the result	Description
value	String	getProperty(key)	Get the value of the property with Key=key (ex: ${property.getProperty("MyKey")})

GBIFlowInput

GBIFlowInput is a Java object that contains all parameters required to start a new GBI Process.

Parameter	Type	Function to retrieve the result	Description
flowId	String	getFlowId()	The GBI Flow Identifier
parameters	Map<String, String>	getParameters()	Map of all Input Parameters required by GBI Flow
correlationId	String	getCorrelationId()	System generated correlationId to be used as input in Camunda object that waits for GBI Flow termination

GBIFlowOutput

GBIFlowOutput is a Java object that contains all parameters returned from GBI Process.

Parameter	Function to retrieve the result	Type	Description
outcome	getOutcome()	String	The GBI Flow return code
parameters	getParameters()	Map<String, String>	Map of all Output Parameters returned by GBI Flow
correlationId	getCorrelationId()	String	System generated correlationId used for process correlation