Package org.matsim.utils.objectattributes

Packages
package	attributable
package	attributeconverters

Classes
interface	AttributeConverter
class	FailingObjectAttributes
class	ObjectAttributes
class	ObjectAttributesConverter
class	ObjectAttributesUtils
class	ObjectAttributesXmlReader
class	ObjectAttributesXmlWriter
class	RunObjectAttributesExample
class	StringDoubleMap

Detailed Description

Supports keeping track of arbitrary attributes for identifiable objects.

An example usage can be seen in org.matsim.utils.objectattributes.RunObjectAttributesExample.

Design thoughts

I think of ObjectAttributes (OA) as a way to provide specific additional data to algorithms and modules. Typically, specialized algorithms/modules might require additional data than what is available by default in MATSim's data container (like population, network). For example, modules could need information about persons' income, a node's z-coordinate, or a link's curviness.

Important to consider is that the algorithm always has to specify what additional data it needs so it can access it. In the example above, an algorithm that needs a person's income needs to know the name of the attribute containing the income. Typically, it could do so by providing a setter setPersonIncomeAttributeName(String) or even exposing it as a config-parameter.

This implies that modules should always just access a few specific attributes, but they should never have the need to just access all attributes and then maybe figure out what they could do with the available attributes, probably even guessing some interpretation of the attributes based on their names. <strike>For this reason, there is no method available directly in org.matsim.utils.objectattributes.ObjectAttributes that returns all attributes for a specific object. Only getters for single, named attributes are providers. </strike>