ilog.views.gantt.project

Class IlvGanttDataSource

java.lang.Object

ilog.views.gantt.project.IlvGanttDataSource

Direct Known Subclasses:

IlvGanttJDBCDataSource, IlvGanttXMLDataSource

public abstract class IlvGanttDataSource
extends Object

This class defines a data source for the Gantt component.

A data source is an object that can read and (optionally) write Gantt data through its read(ilog.views.gantt.IlvGanttModel) and write(ilog.views.gantt.IlvGanttModel) methods.

Predefined implementations of this abstract class are:

• IlvGanttXMLDataSource, that reads and writes data from XML files,
• IlvGanttJDBCDataSource, that reads data from a database through the JDBC API.

Data sources can be serialized inside "configuration files" (see IlvGanttProjectConfiguration). Serializing a data source must not be confused with reading/writing data represented by the data source. Serializing a data source means writing its configuration parameters to an XML configuration file. For example, a database source will have parameters like the database URL, the SQL queries, and so forth. These parameters can be saved (serialized) to an XML file and reloaded (deserialized) later to recreate the data source. Serializing and deserializing data sources is done through the serialize(org.w3c.dom.Element, java.net.URL) and deserialize(org.w3c.dom.Element, java.net.URL) methods.

Since:

JViews 6.0

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	IlvGanttDataSource() Protected constructor to prevent instantiation.

Method Summary

Modifier and Type	Method and Description
boolean	areActivitiesConfigured() Returns whether this data source defines a configuration for activity data.
boolean	areConstraintsConfigured() Returns whether this data source defines a configuration for constraint data.
boolean	areReservationsConfigured() Returns whether this data source defines a configuration for reservation data.
boolean	areResourcesConfigured() Returns whether this data source defines a configuration for resource data.
static IlvGanttDataSource	deserialize(Element element, URL baseURL) Deserializes a data source from the specified DOM element.
protected abstract void	deserializeImpl(Element element) This method must be implemented by subclasses to read their parameters from an XML configuration file.
protected URL	getBaseURL() Returns the base URL to or from which this data source is being deserialized.
String	getDescription() Returns a description of this data source.
abstract void	read(IlvGanttModel ganttModel) Reads data from this data source into an IlvGanttModel
void	serialize(Element element, URL baseURL) Serializes this data source to the specified DOM element.
protected abstract void	serializeImpl(Element element) This method must be implemented by subclasses to save their parameters to the XML configuration file.
boolean	supportsWrite() Gets if this data source supports writing.
abstract void	write(IlvGanttModel ganttModel) Write data from an IlvGanttModel to this data source.

Methods inherited from class java.lang.Object

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

Constructor Detail

IlvGanttDataSource

protected IlvGanttDataSource()

Protected constructor to prevent instantiation.

Method Detail

read

public abstract void read(IlvGanttModel ganttModel)
                   throws Exception

Reads data from this data source into an IlvGanttModel

Parameters:

ganttModel - The Gantt model that will contain the data read from this data source.

Throws:

Exception - If an exception occurs while reading data.

write

public abstract void write(IlvGanttModel ganttModel)
                    throws Exception

Write data from an IlvGanttModel to this data source.

This method may have an empty implementation if the data source is read-only. Read-only data sources must return false from the supportsWrite() method.

Parameters:

ganttModel - The Gantt model that contains the data to be saved to the data source.

Throws:

Exception - If an exception occurs while writing data.

supportsWrite

public boolean supportsWrite()

Gets if this data source supports writing. Read-only data sources must return false.

The default implementation returns false. This method must be overridden by subclasses that support writing.

Returns:

true if this data source supports writing.

getDescription

public String getDescription()

Returns a description of this data source.

This default implementation returns the URL from which the data source was deserialized.

Returns:

the description of this data source.

areActivitiesConfigured

public boolean areActivitiesConfigured()

Returns whether this data source defines a configuration for activity data. This default implementation returns true. Subclasses can override this method if the data source has certain states in which activity data will not be read or written to the Gantt data model. For example, a JDBC data source might not have a query defined for activities or a flat-file data source might not have a file defined for activity import.

Returns:

true if this data source defines a configuration for activity data.

areResourcesConfigured

public boolean areResourcesConfigured()

Returns whether this data source defines a configuration for resource data. This default implementation returns true. Subclasses can override this method if the data source has certain states in which resource data will not be read or written to the Gantt data model. For example, a JDBC data source might not have a query defined for resources or a flat-file data source might not have a file defined for resource import.

Returns:

true if this data source defines a configuration for resource data.

areConstraintsConfigured

public boolean areConstraintsConfigured()

Returns whether this data source defines a configuration for constraint data. This default implementation returns true. Subclasses can override this method if the data source has certain states in which constraint data will not be read or written to the Gantt data model. For example, a JDBC data source might not have a query defined for constraints or a flat-file data source might not have a file defined for constraint import.

Returns:

true if this data source defines a configuration for constraint data.

areReservationsConfigured

public boolean areReservationsConfigured()

Returns whether this data source defines a configuration for reservation data. This default implementation returns true. Subclasses can override this method if the data source has certain states in which reservation data will not be read or written to the Gantt data model. For example, a JDBC data source might not have a query defined for reservations or a flat-file data source might not have a file defined for reservation import.

Returns:

true if this data source defines a configuration for reservation data.

serialize

public final void serialize(Element element,
                            URL baseURL)
                     throws Exception

Serializes this data source to the specified DOM element.

Serializing a data source means saving its parameters to an XML configuration file. Serializing a data source must not be confused with requesting the data source to write the Gantt data model.

This method sets the "class" attribute of the element to the class name of this data source, and then calls serializeImpl(org.w3c.dom.Element) to let subclasses save their own configuration parameters.

Parameters:

element - The DOM element to which the data source parameters are written.

baseURL - The URL to which the configuration is being saved. This URL can be used to save URL parameters of the data source as relative URLs.

Throws:

Exception - If an exception occurs while serializing the data source.

serializeImpl

protected abstract void serializeImpl(Element element)
                               throws Exception

This method must be implemented by subclasses to save their parameters to the XML configuration file.

Parameters:

element - The DOM element to which the data source parameters are written.

Throws:

Exception - If an exception occurs while serializing the data source.

deserialize

public static IlvGanttDataSource deserialize(Element element,
                                             URL baseURL)
                                      throws Exception

Deserializes a data source from the specified DOM element.

Deserializing a data source means reading its parameters from an XML configuration file. Deserializing a data source must not be confused with requesting the data source to read the Gantt data model.

This method reads the data source's class name, creates an instance of this class, and then calls deserializeImpl(org.w3c.dom.Element) to let subclasses read their own configuration parameters.

Parameters:

element - The DOM element from which the data source parameters are read.

baseURL - The URL from which the configuration is being read. URL parameters of this data source may be relative to this base URL.

Returns:

a IlvGanttDataSource.

Throws:

Exception - If an exception occurs while deserializing the data source.

deserializeImpl

protected abstract void deserializeImpl(Element element)
                                 throws Exception

This method must be implemented by subclasses to read their parameters from an XML configuration file.

Parameters:

element - The DOM element to which the data source parameters are written.

Throws:

Exception - If an exception occurs while deserializing the data source.

getBaseURL

protected URL getBaseURL()

Returns the base URL to or from which this data source is being deserialized. This URL can be used to save URL parameters of the data source as relative URLs.

Returns:

the base URL.