org.yawlfoundation.yawl.elements.data.external

Class AbstractExternalDBGateway

java.lang.Object

org.yawlfoundation.yawl.elements.data.external.AbstractExternalDBGateway

Direct Known Subclasses:

SimpleExternalDBGatewayImpl

public abstract class AbstractExternalDBGateway
extends java.lang.Object

Author: Michael Adams Creation Date: 8/07/2009

Field Summary

Fields

Modifier and Type	Field and Description
protected HibernateEngine	_dbEngine
protected org.apache.logging.log4j.Logger	_log

Constructor Summary

Constructors

Constructor and Description
AbstractExternalDBGateway()

Method Summary

Modifier and Type	Method and Description
protected void	configureSession(java.lang.String propertiesFileName, java.util.List<java.lang.Class> classes) Configures the engine to the database specified in a properties file
protected void	configureSession(java.lang.String dialect, java.lang.String driver, java.lang.String url, java.lang.String username, java.lang.String password, java.util.List<java.lang.Class> classes) Configures the engine to the database specified.
abstract java.lang.String	getDescription()
abstract Element	populateCaseData(YSpecificationID specID, java.lang.String caseID, java.util.List<YParameter> inputParams, java.util.List<YVariable> localVars, Element caseDataTemplate) Populates the case data template passed with values selected from a database.
abstract Element	populateTaskParameter(YTask task, YParameter param, Element caseData) Populates the task parameter passed with a value selected from a database.
java.lang.String	toXML()
abstract void	updateFromCaseData(YSpecificationID specID, java.lang.String caseID, java.util.List<YParameter> outputParams, Element updatingData) Update the database with the case's values.
abstract void	updateFromTaskCompletion(java.lang.String paramName, Element outputData, Element caseData) Update the database with the workitem's values.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

_log

protected org.apache.logging.log4j.Logger _log

_dbEngine

protected HibernateEngine _dbEngine

Constructor Detail

AbstractExternalDBGateway

public AbstractExternalDBGateway()

Method Detail

configureSession

protected void configureSession(java.lang.String dialect,
                                java.lang.String driver,
                                java.lang.String url,
                                java.lang.String username,
                                java.lang.String password,
                                java.util.List<java.lang.Class> classes)

Configures the engine to the database specified. Examples given are for postgres.

Parameters:

dialect - the database dialect (e.g. "org.hibernate.dialect.PostgreSQLDialect")

driver - the database driver (e.g. "org.postgresql.Driver")

url - the database url (e.g. "jdbc:postgresql:yawl")

username - the logon name for the database

password - the logon password

classes - a list of classes for Hibernate to use to converse with the underlying tables (can be null if no classes are involved)

configureSession

protected void configureSession(java.lang.String propertiesFileName,
                                java.util.List<java.lang.Class> classes)

Configures the engine to the database specified in a properties file

Parameters:

propertiesFileName - the full path & name of the properties file

toXML

public java.lang.String toXML()

getDescription

public abstract java.lang.String getDescription()

Returns:

a user-understandable description of the use of the particular extending class, which will be seen in a list in the editor and from which the user can choose the class.

populateTaskParameter

public abstract Element populateTaskParameter(YTask task,
                                              YParameter param,
                                              Element caseData)

Populates the task parameter passed with a value selected from a database. Called by the engine to populate a workitem when the workitem starts.

Parameters:

task - the task template for the starting workitem.

param - the name of the parameter that requires values.

caseData - the current set of case variables and values.

Returns:

an Element named after the param (use param.getName()), populated with the appropriate value.

updateFromTaskCompletion

public abstract void updateFromTaskCompletion(java.lang.String paramName,
                                              Element outputData,
                                              Element caseData)

Update the database with the workitem's values. Called by the engine when the workitem completes.

Parameters:

paramName - the name of the task of which this workitem is an instance.

outputData - the datalist from which the corresponding database values are to be updated.

caseData - the current set of case variables and values.

populateCaseData

public abstract Element populateCaseData(YSpecificationID specID,
                                         java.lang.String caseID,
                                         java.util.List<YParameter> inputParams,
                                         java.util.List<YVariable> localVars,
                                         Element caseDataTemplate)

Populates the case data template passed with values selected from a database. Called by the engine to populate the case-level variables when the case starts. Note that the the returned Element MUST be correctly populated with a value for each input parameter. Local variables are passed so that their initial values may (optionally) be changed, if required; to do so, change the value directly within each variable - local variable values are NOT to be included in the returned Element.

Parameters:

specID - the specification identifier of the case.

caseID - the case identifier.

inputParams - the input parameters that require values.

localVars - the local variables (optionally change their initial values).

caseDataTemplate - the data structure that requires values.

Returns:

an Element of the same structure as 'caseDataTemplate', with populated values.

updateFromCaseData

public abstract void updateFromCaseData(YSpecificationID specID,
                                        java.lang.String caseID,
                                        java.util.List<YParameter> outputParams,
                                        Element updatingData)

Update the database with the case's values. Called by the engine when the case completes.

Parameters:

specID - the specification identifier of the case.

caseID - the case identifier.

outputParams - the output parameters for the case.

updatingData - the datalist from which the corresponding database values are to be updated.