org.glassfish.pfl.dynamic.copyobject.impl

Class ClassCopierBase

java.lang.Object

org.glassfish.pfl.dynamic.copyobject.impl.ClassCopierBase

All Implemented Interfaces:

ClassCopier

Direct Known Subclasses:

ClassCopierOrdinaryImpl

public abstract class ClassCopierBase
extends Object
implements ClassCopier

A convenient base class for making ClassCopier types. This takes care of checking oldToNew and updating oldToNew when an actual copy is made. All subclasses must override createCopy, which allocates a new result. In some simple cases, this is all that is needed. In the more complex cases, doCopy must also be overridden to make the actual copy.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ClassCopierBase(String name) Pass a name here that can be used for toString, hashCode, and equals.
protected	ClassCopierBase(String name, boolean isReflective)

Method Summary

Methods

Modifier and Type	Method and Description
Object	copy(Map<Object,Object> oldToNew, Object source) Make the actual copy of source, using oldToNew to preserve aliasing.
protected abstract Object	createCopy(Object source) Create a copy of source.
protected Object	doCopy(Map<Object,Object> oldToNew, Object source, Object result) Do the copying of data from source to result.
boolean	equals(Object obj)
int	hashCode()
boolean	isReflectiveClassCopier() We need to know whether this class copier operates via reflection or not, as the reflective class copier must be able to tell when a super class is copied by an incompatible copier.
String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ClassCopierBase

protected ClassCopierBase(String name)

Pass a name here that can be used for toString, hashCode, and equals. All different ClassCopier classes derived from this base should have unique names.

ClassCopierBase

protected ClassCopierBase(String name,
               boolean isReflective)

Method Detail

toString

public final String toString()

Overrides:

toString in class Object

hashCode

public final int hashCode()

Overrides:

hashCode in class Object

equals

public final boolean equals(Object obj)

Overrides:

equals in class Object

copy

public final Object copy(Map<Object,Object> oldToNew,
          Object source)
                  throws ReflectiveCopyException

Make the actual copy of source, using oldToNew to preserve aliasing. This first checks to see whether source has been previously copied. If so, the value obtained from oldToNew is returned. Otherwise,

1. createCopy( source ) is called to create a new copy of source.
2. The new copy is placed in oldToNew with source as its key.
3. doCopy is called to complete the copy.

This split into two phases isolates all subclasses from the need to update oldToNew. It accommodates simple cases (arrays of primitives for example) that only need to define createCopy, as well as more complex case (general objects) that must first create the copy, update oldToNew, and then do the copy, as otherwise self-references would cause infinite recursion.

Specified by:

copy in interface ClassCopier

Throws:

ReflectiveCopyException

isReflectiveClassCopier

public boolean isReflectiveClassCopier()

Description copied from interface: ClassCopier

We need to know whether this class copier operates via reflection or not, as the reflective class copier must be able to tell when a super class is copied by an incompatible copier.

Specified by:

isReflectiveClassCopier in interface ClassCopier

createCopy

protected abstract Object createCopy(Object source)
                              throws ReflectiveCopyException

Create a copy of source. The copy may or may not be fully initialized. This method must always be overridden in a subclass.

Throws:

ReflectiveCopyException

doCopy

protected Object doCopy(Map<Object,Object> oldToNew,
            Object source,
            Object result)
                 throws ReflectiveCopyException

Do the copying of data from source to result. This just returns the result by default, but it may be overrideden in a subclass. When this method completes, result must be fully initialized.

Throws:

ReflectiveCopyException