com.threerings.delta
Class ReflectiveDelta

java.lang.Object
  com.threerings.delta.Delta
      com.threerings.delta.ReflectiveDelta

All Implemented Interfaces:

Streamable

Direct Known Subclasses:

ActorDelta

public class ReflectiveDelta
extends Delta

A delta object that uses reflection to compare and modify the objects' fields. Note that unchanged object fields will be preserved by reference.

Nested Class Summary

protected static class	ReflectiveDelta.ClassMapping Contains cached information about a class.
protected static class	ReflectiveDelta.FieldHandler Handles a particular field.
protected static class	ReflectiveDelta.FinalFieldHandler Base class for final field handlers.

Nested classes/interfaces inherited from interface com.threerings.io.Streamable

Streamable.Closure

Field Summary

protected static Map<Class<?>,ReflectiveDelta.ClassMapping>	_classes Cached mappings for deltable classes.
protected Class<?>	_clazz The object class.
protected BareArrayMask	_mask The mask indicating which fields have changed.
protected Object[]	_values The values for each of the object's changed fields (either a new value or a Delta object).
protected static ReflectiveDelta.FieldHandler	FINAL_OBJECT_FIELD_HANDLER Handler for final object fields.
protected static Map<Class<?>,ReflectiveDelta.FieldHandler>	FINAL_PRIMITIVE_FIELD_HANDLERS Field handlers for final primitive fields mapped by class.
protected static ReflectiveDelta.FieldHandler	OBJECT_FIELD_HANDLER Handler for object fields.
protected static Map<Class<?>,ReflectiveDelta.FieldHandler>	PRIMITIVE_FIELD_HANDLERS Field handlers for primitive fields mapped by class.

Fields inherited from class com.threerings.delta.Delta

_classStreamer, _creators, _none, _wrapperStreamers

Constructor Summary

ReflectiveDelta()
No-arg constructor for deserialization.

ReflectiveDelta(Object original, Object revised)
Creates a new reflective delta that transforms the original object into the revised object (both of which must be instances of the same class).

Method Summary

Object	apply(Object original) Applies this delta to the specified object.
protected static void	collectFields(Class<?> clazz, List<Field> fields) Collects all appropriate fields of the specified class (and its superclasses) and places them in the provided results object.
protected static ReflectiveDelta.ClassMapping	getClassMapping(Class<?> clazz) Returns the class mapping for the specified class.
boolean	isEmpty() Checks whether the delta is empty.
Delta	merge(Delta other) Merges this delta with another.
protected void	populateMerged(ReflectiveDelta other, ReflectiveDelta merged) Populates the merged delta.
void	readObject(ObjectInputStream in) Custom read method.
String	toString()
void	writeObject(ObjectOutputStream out) Custom write method.

Methods inherited from class com.threerings.delta.Delta

checkDeltable, createDelta

Methods inherited from class java.lang.Object

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

Field Detail

_clazz

protected Class<?> _clazz

The object class.

_mask

protected BareArrayMask _mask

The mask indicating which fields have changed.

_values

protected Object[] _values

The values for each of the object's changed fields (either a new value or a Delta object).

_classes

protected static Map<Class<?>,ReflectiveDelta.ClassMapping> _classes

Cached mappings for deltable classes.

PRIMITIVE_FIELD_HANDLERS

protected static final Map<Class<?>,ReflectiveDelta.FieldHandler> PRIMITIVE_FIELD_HANDLERS

Field handlers for primitive fields mapped by class.

FINAL_PRIMITIVE_FIELD_HANDLERS

protected static final Map<Class<?>,ReflectiveDelta.FieldHandler> FINAL_PRIMITIVE_FIELD_HANDLERS

Field handlers for final primitive fields mapped by class.

OBJECT_FIELD_HANDLER

protected static final ReflectiveDelta.FieldHandler OBJECT_FIELD_HANDLER

Handler for object fields.

FINAL_OBJECT_FIELD_HANDLER

protected static final ReflectiveDelta.FieldHandler FINAL_OBJECT_FIELD_HANDLER

Handler for final object fields.

Constructor Detail

ReflectiveDelta

public ReflectiveDelta(Object original,
                       Object revised)

Creates a new reflective delta that transforms the original object into the revised object (both of which must be instances of the same class).

ReflectiveDelta

public ReflectiveDelta()

No-arg constructor for deserialization.

Method Detail

isEmpty

public boolean isEmpty()

Checks whether the delta is empty.

writeObject

public void writeObject(ObjectOutputStream out)
                 throws IOException

Custom write method.

Throws:

IOException

readObject

public void readObject(ObjectInputStream in)
                throws IOException,
                       ClassNotFoundException

Custom read method.

Throws:

IOException

ClassNotFoundException

apply

public Object apply(Object original)

Description copied from class: Delta

Applies this delta to the specified object.

Specified by:

apply in class Delta

Returns:

a new object incorporating the changes represented by this delta.

merge

public Delta merge(Delta other)

Description copied from class: Delta

Merges this delta with another.

Specified by:

merge in class Delta

Returns:

a new delta containing the changes included in both.

toString

public String toString()

Overrides:

toString in class Object

populateMerged

protected void populateMerged(ReflectiveDelta other,
                              ReflectiveDelta merged)

Populates the merged delta.

getClassMapping

protected static ReflectiveDelta.ClassMapping getClassMapping(Class<?> clazz)

Returns the class mapping for the specified class.

collectFields

protected static void collectFields(Class<?> clazz,
                                    List<Field> fields)

Collects all appropriate fields of the specified class (and its superclasses) and places them in the provided results object.