agi.foundation.tracking

(agi.foundation.tracking-2024r3.jar)

Class DelegateEntityFilter<TEntity extends IEntityIdentifier>

java.lang.Object

agi.foundation.infrastructure.DefinitionalObject

agi.foundation.tracking.EntityFilter<TEntity>

agi.foundation.tracking.DelegateEntityFilter<TEntity>

Type Parameters:

TEntity - The type of entity.

All Implemented Interfaces:

ICloneWithContext, IEnumerateDependencies, IEquatableDefinition, IFreezable, IThreadAware

public class DelegateEntityFilter<TEntity extends IEntityIdentifier>
extends EntityFilter<TEntity>

An EntityFilter that filters entities based on the result of the specified callback.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	DelegateEntityFilter(DelegateEntityFilter<TEntity> existingInstance, CopyContext context) Initializes a new instance as a copy of an existing instance.
	DelegateEntityFilter(TransactionContext context) Creates a new instance with the specified context, IsMatchMethod (get / set) must be set and DelegateEntityFilter.applyChanges() called before the filter can be used.
	DelegateEntityFilter(TransactionContext context, IsMatchCallback<TEntity> isMatchMethod) Creates a new instance with the specified context and match function.

Method Summary

Modifier and Type	Method and Description
void	applyChanges() Applies the changes to this filter.
protected boolean	checkForSameDefinition(DelegateEntityFilter<TEntity> other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
protected boolean	checkForSameDefinition(EntityFilter<TEntity> other) Checks to determine if another instance has the same definition as this instance and returns true if it does.
Object	clone(CopyContext context) Clones this object using the specified context.
protected int	computeCurrentDefinitionHashCode() Computes a hash code based on the current properties of this object.
protected void	entityMatchingSetup(Transaction transaction) Allows the filter to perform any filter-specific setup at the start of entity matching.
IsMatchCallback<TEntity>	getIsMatchMethod() Gets the delegate which will be called to evaluate DelegateEntityFilter.isMatch(agi.foundation.Transaction, TEntity).
boolean	isMatch(Transaction transaction, TEntity entity) Indicates if the entity matches this filter by returning the result of calling IsMatchMethod (get / set) with the provided transaction and entity.
void	setIsMatchMethod(IsMatchCallback<TEntity> value) Sets the delegate which will be called to evaluate DelegateEntityFilter.isMatch(agi.foundation.Transaction, TEntity).

Methods inherited from class agi.foundation.tracking.EntityFilter

beginEntityMatching, checkForSameDefinition, endEntityMatching, entityMatchingCleanup, getIsThreadSafe, getMatchingEntities, match

Methods inherited from class agi.foundation.infrastructure.DefinitionalObject

areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, areSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, collectionItemsAreSameDefinition, dictionaryItemsAreSameDefinition, enumerateDependencies, freeze, freezeAggregatedObjects, getCollectionHashCode, getCollectionHashCode, getCollectionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDefinitionHashCode, getDictionaryHashCode, getIsFrozen, isSameDefinition, throwIfFrozen

Methods inherited from class java.lang.Object

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

Constructor Detail

DelegateEntityFilter

public DelegateEntityFilter(@Nonnull
                            TransactionContext context)

Creates a new instance with the specified context, IsMatchMethod (get / set) must be set and DelegateEntityFilter.applyChanges() called before the filter can be used.

Parameters:

context - The transaction context to be used.

DelegateEntityFilter

public DelegateEntityFilter(@Nonnull
                            TransactionContext context,
                            IsMatchCallback<TEntity> isMatchMethod)

Creates a new instance with the specified context and match function. The filter is ready to be used immediately.

Parameters:

context - The transaction context to be used.

isMatchMethod - The method to call for the DelegateEntityFilter.isMatch(agi.foundation.Transaction, TEntity) method.

DelegateEntityFilter

protected DelegateEntityFilter(@Nonnull
                               DelegateEntityFilter<TEntity> existingInstance,
                               @Nonnull
                               CopyContext context)

Initializes a new instance as a copy of an existing instance.

See ICloneWithContext.clone(CopyContext) for more information about how to implement this constructor in a derived class.

Parameters:

existingInstance - The existing instance to copy.

context - A CopyContext that controls the depth of the copy.

Throws:

ArgumentNullException - Thrown when existingInstance or context is null.

Method Detail

clone

public Object clone(CopyContext context)

Clones this object using the specified context.

This method should be implemented to call a copy constructor on the class of the object being cloned. The copy constructor should take the CopyContext as a parameter in addition to the existing instance to copy. The copy constructor should first call CopyContext.addObjectMapping(T, T) to identify the newly constructed instance as a copy of the existing instance. It should then copy all fields, using CopyContext.updateReference(T) to copy any reference fields.

A typical implementation of ICloneWithContext:

public static class MyClass implements ICloneWithContext {
    public MyClass(MyClass existingInstance, CopyContext context) {
        context.addObjectMapping(existingInstance, this);
        someReference = context.updateReference(existingInstance.someReference);
    }

    @Override
    public final Object clone(CopyContext context) {
        return new MyClass(this, context);
    }

    private Object someReference;
}

In general, all fields that are reference types should be copied with a call to CopyContext.updateReference(T). There are a couple of exceptions:

1. Fields that are aggregate parts of the object should always be copied. A referenced object is an aggregate if properties or methods on the object being copied can modify the externally-visible value of the referenced object.
2. If the semantics of the referenced object require that it have a single parent, owner, context, etc., and the object being copied is that parent, owner, or context, then the referenced object should always be copied.

If one of these exceptions applies, the CopyContext should be given an opportunity to update the reference before the reference is copied explicitly. Use CopyContext.updateReference(T) to update the reference. If CopyContext.updateReference(T) returns the original object, indicating that the context does not have a replacement registered, then copy the object manually by invoking a Clone method, a copy constructor, or by manually constructing a new instance and copying the values.

alwaysCopy = context.updateReference(existingInstance.alwaysCopy);
if (existingInstance.alwaysCopy != null && alwaysCopy == existingInstance.alwaysCopy) {
    alwaysCopy = (AlwaysCopy) existingInstance.alwaysCopy.clone(context);
}

If you are implementing an evaluator (a class that implements IEvaluator), the IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) method shares some responsibilities with the copy context constructor. Code duplication can be avoided by doing the following:

1. For references to other evaluators ONLY, simply assign the reference in the constructor instead of calling CopyContext.updateReference(T). You should still call CopyContext.updateReference(T) on any references to non-evaluators.
2. Call IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as the last line in the constructor and pass it the same CopyContext passed to the constructor.
3. Implement IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) as normal. See the reference documentation for IEvaluator.updateEvaluatorReferences(agi.foundation.infrastructure.CopyContext) for more information on implementing that method.

public MyClass(MyClass existingInstance, CopyContext context) {
    super(existingInstance, context);
    someReference = context.updateReference(existingInstance.someReference);
    evaluatorReference = existingInstance.evaluatorReference;
    updateEvaluatorReferences(context);
}

@Override
public void updateEvaluatorReferences(CopyContext context) {
    evaluatorReference = context.updateReference(evaluatorReference);
}

@Override
public Object clone(CopyContext context) {
    return new MyClass(this, context);
}

private Object someReference;
private IEvaluator evaluatorReference;

Specified by:

clone in interface ICloneWithContext

Specified by:

clone in class DefinitionalObject

Parameters:

context - The context to use to perform the copy.

Returns:

A new instance which is a copy of this object.

checkForSameDefinition

protected final boolean checkForSameDefinition(EntityFilter<TEntity> other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Specified by:

checkForSameDefinition in class EntityFilter<TEntity extends IEntityIdentifier>

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

checkForSameDefinition

protected boolean checkForSameDefinition(DelegateEntityFilter<TEntity> other)

Checks to determine if another instance has the same definition as this instance and returns true if it does. Derived classes MUST override this method and check all new fields introduced by the derived class for definitional equivalence. It is NOT necessary to check base class fields because the base class will already have done that. When overriding this method, you should NOT call the base implementation because it will return false for all derived-class instances. Derived classes should check the type of other to preserve the symmetric nature of IEquatableDefinition.isSameDefinition(java.lang.Object).

Parameters:

other - The other instance to compare to this one.

Returns:

true if the two objects are defined equivalently; otherwise false.

computeCurrentDefinitionHashCode

protected int computeCurrentDefinitionHashCode()

Computes a hash code based on the current properties of this object. Derived classes MUST override this method and compute a hash code that combines: a unique hash code seed, the base implementation result, and the hash codes of all new fields introduced by the derived class which are used in the DelegateEntityFilter.checkForSameDefinition(agi.foundation.tracking.EntityFilter<TEntity>) method.

Overrides:

computeCurrentDefinitionHashCode in class EntityFilter<TEntity extends IEntityIdentifier>

Returns:

The computed hash code.

getIsMatchMethod

public final IsMatchCallback<TEntity> getIsMatchMethod()

Gets the delegate which will be called to evaluate DelegateEntityFilter.isMatch(agi.foundation.Transaction, TEntity). DelegateEntityFilter.applyChanges() must be called after setting this property in order for the change to take effect.

setIsMatchMethod

public final void setIsMatchMethod(IsMatchCallback<TEntity> value)

Sets the delegate which will be called to evaluate DelegateEntityFilter.isMatch(agi.foundation.Transaction, TEntity). DelegateEntityFilter.applyChanges() must be called after setting this property in order for the change to take effect.

applyChanges

public final void applyChanges()

Applies the changes to this filter. This method must be called after setting the IsMatchMethod (get / set) property in order for the change to take effect. Changes will take effect the next time after calling this method that entities are redistributed within the filter chain with a call to EntityFilterChain.redistributeEntities().

isMatch

public boolean isMatch(Transaction transaction,
                       TEntity entity)

Indicates if the entity matches this filter by returning the result of calling IsMatchMethod (get / set) with the provided transaction and entity.

Specified by:

isMatch in class EntityFilter<TEntity extends IEntityIdentifier>

Parameters:

transaction - The transaction used for getting values from the entity.

entity - The entity to be filtered.

Returns:

true if the entity meets the filter criteria; otherwise false.

entityMatchingSetup

protected void entityMatchingSetup(Transaction transaction)

Allows the filter to perform any filter-specific setup at the start of entity matching. This method is called by EntityFilter.beginEntityMatching(agi.foundation.Transaction).

Overrides:

entityMatchingSetup in class EntityFilter<TEntity extends IEntityIdentifier>

Parameters:

transaction - The transaction to be used to match entities.