uk.ac.ed.epcc.safe.accounting.policy

Class ExpressionPropertyPolicy

java.lang.Object

uk.ac.ed.epcc.safe.accounting.update.AbstractPropertyContainerUpdater

uk.ac.ed.epcc.safe.accounting.policy.BasePolicy

uk.ac.ed.epcc.safe.accounting.policy.ExpressionPropertyPolicy

All Implemented Interfaces:

PropertyContainerPolicy, PropertyContainerUpdater, uk.ac.ed.epcc.webapp.jdbc.table.TransitionSource<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>

public class ExpressionPropertyPolicy
extends BasePolicy
implements uk.ac.ed.epcc.webapp.jdbc.table.TransitionSource<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>

This policy allows derived property expressions to be defined for properties in scope. It also provides a mechanism for ConfigPropertyRegistry objects to be included in scope so that entirely new properties can be defined. This is intended to be a replacement for the DerivedPropertyPolicy so the property definitions are compatible with this and the syntax supported by PropExpressionMapbut it requires additional configuration parameters.

The ConfigPropertyRegistrys added to the PropertyFinder are specified by registry_list.table-name=name [, name]* This defaults to expression

Property definitions are under the control of java properties of the form properties.table-name.name=prop-expression

Author:

spb

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	ExpressionPropertyPolicy.AddDerivedTransition
class	ExpressionPropertyPolicy.AddPropertyTransition

Constructor Summary

Constructors

Constructor and Description
ExpressionPropertyPolicy()

Method Summary

Methods

Modifier and Type	Method and Description
PropExpressionMap	getDerivedProperties(PropExpressionMap previous) return a set of derived property definitions.
java.util.Map<uk.ac.ed.epcc.webapp.model.data.transition.TransitionKey<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>,uk.ac.ed.epcc.webapp.forms.transition.Transition<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>>	getTransitions()
PropertyFinder	initFinder(uk.ac.ed.epcc.webapp.AppContext ctx, PropertyFinder prev, java.lang.String table) Generate a PropertyFinder that will find any PropertyTag generated by this class.

Methods inherited from class uk.ac.ed.epcc.safe.accounting.policy.BasePolicy

parse

Methods inherited from class uk.ac.ed.epcc.safe.accounting.update.AbstractPropertyContainerUpdater

endParse, modifyDefaultTableSpecification, startParse, unique

Methods inherited from class java.lang.Object

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

Methods inherited from interface uk.ac.ed.epcc.safe.accounting.update.PropertyContainerUpdater

endParse, modifyDefaultTableSpecification, startParse

Constructor Detail

ExpressionPropertyPolicy

public ExpressionPropertyPolicy()

Method Detail

initFinder

public PropertyFinder initFinder(uk.ac.ed.epcc.webapp.AppContext ctx,
                        PropertyFinder prev,
                        java.lang.String table)

Description copied from interface: PropertyContainerUpdater

Generate a PropertyFinder that will find any PropertyTag generated by this class. This call should be treated as a secondary constructor and should be called before any other method from this interface.

All properties defined at run-time should have their PropertyTag objects constructed by the time the first call to this method returns. As some parsers properties will generate different things depending on the other properties already in scope this method is passed a PropertyFinder for any properties that may already be in scope. This will include any default parameters specified when the data was uploaded and any properties generated from the database meta-data. Though it is perfectly legal to return a PropertyFinder that returns a superset of the generated properties the only requirement is that the returned finder can find any property that this classes parse method may actually generate values for. So Normally the contents of the super-finder are not included in the result unless these values are actually generated by the parse. If values are generated then a MultiFinder can be populated with the PropertyRegistrys from the generated properties

Specified by:

initFinder in interface PropertyContainerUpdater

prev - PropertyFinder for the higher levels in the call chain.

table - String name of the destination table in case per-table customisation is needed

Returns:

PropertyFinder or null

getDerivedProperties

public PropExpressionMap getDerivedProperties(PropExpressionMap previous)

Description copied from interface: PropertyContainerUpdater

return a set of derived property definitions. Each derived property is defined in terms of a simple expression over other properties (that may themselves be derived properties).

Definitions are allowed for properties that are also generated directly in the parse phase. In this case the parse value should always be used by preference and the derived definition only provides a fall-back implementation if the parse value is unavailable. For example if not persisted in the database layer. This allows one parser/policy to specify a default implementation as a derived property definition which is then overridden by having the same property generated in a parse method of a different policy/parser

Specified by:

getDerivedProperties in interface PropertyContainerUpdater

Overrides:

getDerivedProperties in class AbstractPropertyContainerUpdater

Parameters:

previous - Previous definitions

Returns:

Map modified map

getTransitions

public java.util.Map<uk.ac.ed.epcc.webapp.model.data.transition.TransitionKey<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>,uk.ac.ed.epcc.webapp.forms.transition.Transition<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>> getTransitions()

Specified by:

getTransitions in interface uk.ac.ed.epcc.webapp.jdbc.table.TransitionSource<uk.ac.ed.epcc.webapp.jdbc.table.TableTransitionTarget>