com.goldencode.p2j.util

Class ObjectVar<T extends _BaseObject_>

java.lang.Object

com.goldencode.p2j.util.LazyUndoable

com.goldencode.p2j.util.BaseDataType

com.goldencode.p2j.util.object<T>

com.goldencode.p2j.util.ObjectVar<T>

All Implemented Interfaces:

Undoable, java.io.Externalizable, java.io.Serializable, java.lang.Comparable

public class ObjectVar<T extends _BaseObject_>
extends object<T>

Wrapper class for all OO 4GL variable definitions. This is needed for compatibility with unknown value, assignment, parameter passing, DELETE, SESSION:FIRST-OBJECT/LAST-OBJECT and UNDO.

This implementation takes care of counting the references of assigned legacy 4GL class instances.

Object variables are instantiated as ObjectVar (by the TypeFactory or ArrayAssigner); this is required to enable the reference counting ONLY for the instances which were defined as variables in the legacy code. Also, they are registered at the defining top-level block via ObjectOps.registerPending(java.lang.Object...) when they are defined via TypeFactory, so that when they get out of scope, their referenced object can update the counter.

This type can't be sub-classed, as Hibernate types are dependent on it.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class com.goldencode.p2j.util.BaseDataType

BaseDataType.Type, BaseDataType.WrapperHandler

Field Summary

Fields inherited from class com.goldencode.p2j.util.object

helper, ref

Constructor Summary

Constructors

Constructor and Description
ObjectVar() Default ctor.
ObjectVar(java.lang.Class<T> cls) Initialize this object reference, allowing only assignment to objects compatible with the specified type.
ObjectVar(ObjectVar var) Create a copy of the specified object variable.

Method Summary

Modifier and Type	Method and Description
void	assign(object value) Sets the state (data and unknown value) of this instance based on the state of the passed instance.
protected void	decrement() Decrement the reference counter for this instance.
protected void	increment() Increment the reference counter for this instance.
void	setUnknown() Sets the state of this instance's unknown value flag or state to true.

Methods inherited from class com.goldencode.p2j.util.object

_isValid, assign, assign, assign, compareTo, defaultFormatString, duplicate, fromResourceId, getType, hashCode, instantiateDefault, instantiateUnknown, isIncompatibleTypesOnConversion, isTracked, isUnknown, isValid, readExternal, ref, resourceId, set, toString, toString, toStringExport, toStringMessage, type, writeExternal

Methods inherited from class com.goldencode.p2j.util.BaseDataType

assign, assign, calcFormatLength, createProxy, createProxy, deepCopy, elementsOfType, equals, fallback, formatLength, fromTypeName, generateDefault, generateUnknown, getAssigner, getSize, getTypeName, incompatibleTypesOnConversion, initialize, initializeDefaultExtent, instantiateDefaultExtent, invalidInitializer, isAllKnown, isAllKnown, isAssignDirect, isProxy, isUnknownValue, maximum, minimum, notUnknownValue, sameType, val, variable

Methods inherited from class com.goldencode.p2j.util.LazyUndoable

changed, checkUndoable, checkUndoable, checkUndoable, getTransLevel, isGlobal, isUndoable, markUndoable, popBlock, rollback, setGlobal

Methods inherited from class java.lang.Object

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

Constructor Detail

ObjectVar

public ObjectVar()

Default ctor. Internally used during construction of default instances.

ObjectVar

public ObjectVar(java.lang.Class<T> cls)

Initialize this object reference, allowing only assignment to objects compatible with the specified type.

Parameters:

cls - The type of references this object can hold.

ObjectVar

public ObjectVar(ObjectVar var)

Create a copy of the specified object variable.

Reference counting will be performed.

Parameters:

var - The variable to copy.

Method Detail

assign

public void assign(object value)

Sets the state (data and unknown value) of this instance based on the state of the passed instance.

Reference management is performed for the old and new values.

Overrides:

assign in class object<T extends _BaseObject_>

Parameters:

value - The instance from which to copy state.

setUnknown

public void setUnknown()

Sets the state of this instance's unknown value flag or state to true.

Warning: the data stored in this instance will be invalid after calling this method.

Overrides:

setUnknown in class object<T extends _BaseObject_>

decrement

protected void decrement()

Decrement the reference counter for this instance.

Overrides:

decrement in class object<T extends _BaseObject_>

increment

protected void increment()

Increment the reference counter for this instance.

Overrides:

increment in class object<T extends _BaseObject_>