org.apache.openjpa.persistence.criteria
Class PathImpl<Z,X>

java.lang.Object
  org.apache.openjpa.persistence.criteria.SelectionImpl<X>
      org.apache.openjpa.persistence.criteria.ExpressionImpl<X>
          org.apache.openjpa.persistence.criteria.PathImpl<Z,X>

Type Parameters:

Z - the type of the parent path

X - the type of this path

All Implemented Interfaces:

Expression<X>, Path<X>, Selection<X>, TupleElement<X>, CriteriaExpression

Direct Known Subclasses:

FetchPathImpl, FromImpl, Joins.MapKey

 class PathImpl<Z,X>
extends ExpressionImpl<X>
implements Path<X>

Path is an expression representing a persistent attribute traversed from a parent path. The type of the path is the type of the persistent attribute. If the persistent attribute is bindable, then further path can be traversed from this path.

Author:

Pinaki Poddar, Fay Wang

Field Summary

protected Members.Member<? super Z,?>	_member
protected PathImpl<?,Z>	_parent

Constructor Summary

protected	PathImpl(Class<X> cls) Protected constructor use by root path which neither represent a member nor has a parent.
	PathImpl(PathImpl<?,Z> parent, Members.Member<? super Z,?> member, Class<X> cls) Create a path from the given parent representing the given member.

Method Summary

StringBuilder	asValue(AliasContext q) Get a string representation of this node as a value in the context of the given query.
StringBuilder	asVariable(AliasContext q) Get a string representation of this node as a variable in the context of the given query.
<K,V,M extends Map<K,V>> Expression<M>	get(MapAttribute<X,K,V> map) Gets a new path that represents the given map-valued attribute from this path.
<E,C extends Collection<E>> Expression<C>	get(PluralAttribute<X,C,E> coll) Gets a new path that represents the given multi-valued attribute from this path.
<Y> Path<Y>	get(SingularAttribute<? super X,Y> attr) Gets a new path that represents the given single-valued attribute from this path.
<Y> Path<Y>	get(String attName) Gets a new path that represents the attribute of the given name from this path.
PathImpl<?,?>	getCorrelatedJoin(PathImpl<?,?> path)
PathImpl<?,?>	getCorrelatedPath() Gets the path correlated to this path, if any.
PathImpl<?,?>	getCorrelatedRoot(SubqueryImpl<?> subquery)
protected FieldMetaData	getEmbeddedFieldMetaData(FieldMetaData fmd) Gets the field that may have been embedded inside the given field.
protected Members.Member<?,?>	getInnermostMember(PathImpl<?,?> parent, Members.Member<?,?> member)
PathImpl<?,?>	getInnermostParentPath() Gets the path that originates this traversal.
Members.Member<? extends Z,X>	getMember()
Bindable<X>	getModel() Gets the bindable object that corresponds to the path expression.
Path<Z>	getParentPath() Gets the parent of this path or null if this path is the root.
Type<?>	getType()
boolean	inSubquery(SubqueryImpl<?> subquery) Affirms if this receiver occurs in the roots of the given subquery.
boolean	isCorrelated() Affirms if this path is correlated to another path.
void	setCorrelatedPath(PathImpl<?,?> correlatedPath) Makes this path correlated to the given path.
Value	toValue(ExpressionFactory factory, CriteriaQueryImpl<?> q) Convert this path to a kernel path.
protected void	traversePath(PathImpl<?,?> parent, Path path, FieldMetaData fmd)
Expression<Class<? extends X>>	type() Get the type() expression corresponding to this path.

Methods inherited from class org.apache.openjpa.persistence.criteria.ExpressionImpl

as, in, in, in, in, isNotNull, isNull, toKernelExpression

Methods inherited from class org.apache.openjpa.persistence.criteria.SelectionImpl

acceptVisit, alias, asProjection, assertValidName, getAlias, getCompoundSelectionItems, getJavaType, isAliased, isAutoAliased, isCompoundSelection, setAutoAlias

Methods inherited from class java.lang.Object

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

Methods inherited from interface javax.persistence.criteria.Expression

as, in, in, in, in, isNotNull, isNull

Methods inherited from interface javax.persistence.criteria.Selection

alias, getCompoundSelectionItems, isCompoundSelection

Methods inherited from interface javax.persistence.TupleElement

getAlias, getJavaType

Field Detail

_parent

protected final PathImpl<?,Z> _parent

_member

protected final Members.Member<? super Z,?> _member

Constructor Detail

PathImpl

protected PathImpl(Class<X> cls)

Protected constructor use by root path which neither represent a member nor has a parent.

PathImpl

public PathImpl(PathImpl<?,Z> parent,
                Members.Member<? super Z,?> member,
                Class<X> cls)

Create a path from the given parent representing the given member.

Parameters:

parent - the path from which this path needs to be constructed. Must not be null.

member - the persistent property that represents this path.

cls - denotes the type expressed by this path.

Method Detail

getModel

public Bindable<X> getModel()

Gets the bindable object that corresponds to the path expression.

Specified by:

getModel in interface Path<X>

Throws:

IllegalArgumentException - if this path is not bindable

getParentPath

public final Path<Z> getParentPath()

Gets the parent of this path or null if this path is the root.

Specified by:

getParentPath in interface Path<X>

getInnermostParentPath

public PathImpl<?,?> getInnermostParentPath()

Gets the path that originates this traversal. Can be itself if this path is the root.

getEmbeddedFieldMetaData

protected FieldMetaData getEmbeddedFieldMetaData(FieldMetaData fmd)

Gets the field that may have been embedded inside the given field. For example, a given primary key field which is using an embedded class as a complex primary key.

Parameters:

fmd - a given field

Returns:

the embedded field or the given field itself

getInnermostMember

protected Members.Member<?,?> getInnermostMember(PathImpl<?,?> parent,
                                                 Members.Member<?,?> member)

setCorrelatedPath

public void setCorrelatedPath(PathImpl<?,?> correlatedPath)

Makes this path correlated to the given path.

getCorrelatedPath

public PathImpl<?,?> getCorrelatedPath()

Gets the path correlated to this path, if any.

isCorrelated

public boolean isCorrelated()

Affirms if this path is correlated to another path.

toValue

public Value toValue(ExpressionFactory factory,
                     CriteriaQueryImpl<?> q)

Convert this path to a kernel path.

Specified by:

toValue in class ExpressionImpl<X>

Parameters:

factory - creates the kernel expression

q - the query definition context of this expression

Returns:

an equivalent kernel value

getCorrelatedRoot

public PathImpl<?,?> getCorrelatedRoot(SubqueryImpl<?> subquery)

getCorrelatedJoin

public PathImpl<?,?> getCorrelatedJoin(PathImpl<?,?> path)

inSubquery

public boolean inSubquery(SubqueryImpl<?> subquery)

Affirms if this receiver occurs in the roots of the given subquery.

traversePath

protected void traversePath(PathImpl<?,?> parent,
                            Path path,
                            FieldMetaData fmd)

get

public <Y> Path<Y> get(SingularAttribute<? super X,Y> attr)

Gets a new path that represents the given single-valued attribute from this path.

Specified by:

get in interface Path<X>

get

public <E,C extends Collection<E>> Expression<C> get(PluralAttribute<X,C,E> coll)

Gets a new path that represents the given multi-valued attribute from this path.

Specified by:

get in interface Path<X>

get

public <K,V,M extends Map<K,V>> Expression<M> get(MapAttribute<X,K,V> map)

Gets a new path that represents the given map-valued attribute from this path.

Specified by:

get in interface Path<X>

get

public <Y> Path<Y> get(String attName)

Gets a new path that represents the attribute of the given name from this path.

Specified by:

get in interface Path<X>

Throws:

IllegalArgumentException - if this path represents a basic attribute that is can not be traversed further.

getType

public Type<?> getType()

getMember

public Members.Member<? extends Z,X> getMember()

type

public Expression<Class<? extends X>> type()

Get the type() expression corresponding to this path.

Specified by:

type in interface Path<X>

asValue

public StringBuilder asValue(AliasContext q)

Description copied from interface: CriteriaExpression

Get a string representation of this node as a value in the context of the given query.

Specified by:

asValue in interface CriteriaExpression

Overrides:

asValue in class SelectionImpl<X>

asVariable

public StringBuilder asVariable(AliasContext q)

Description copied from interface: CriteriaExpression

Get a string representation of this node as a variable in the context of the given query.

Specified by:

asVariable in interface CriteriaExpression

Overrides:

asVariable in class SelectionImpl<X>