Class CoalesceExpressionStateObject
java.lang.Object
org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractStateObject
org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractEncapsulatedExpressionStateObject
org.eclipse.persistence.jpa.jpql.tools.model.query.CoalesceExpressionStateObject
- All Implemented Interfaces:
ListHolderStateObject<StateObject>
,StateObject
public class CoalesceExpressionStateObject
extends AbstractEncapsulatedExpressionStateObject
implements ListHolderStateObject<StateObject>
A
COALESCE
expression returns null
if all its arguments evaluate
to null
, and the value of the first non-null
argument otherwise.
The return type is the type returned by the arguments if they are all of the same type, otherwise it is undetermined.
BNF:
coalesce_expression::= COALESCE(scalar_expression {, scalar_expression}+)
- Since:
- 2.4
- Version:
- 2.4
- See Also:
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Field Summary
Modifier and TypeFieldDescriptionstatic final String
Notifies the content of the state object list has changed. -
Constructor Summary
ConstructorDescriptionCreates a newCoalesceExpressionStateObject
.CoalesceExpressionStateObject
(StateObject parent, String... items) Creates a newCoalesceExpressionStateObject
.CoalesceExpressionStateObject
(StateObject parent, List<StateObject> items) Creates a newCoalesceExpressionStateObject
.CoalesceExpressionStateObject
(StateObject parent, StateObject... items) Creates a newCoalesceExpressionStateObject
. -
Method Summary
Modifier and TypeMethodDescriptionvoid
accept
(StateObjectVisitor visitor) Visits thisStateObject
by the givenvisitor
.protected void
addChildren
(List<StateObject> children) Adds the children of thisStateObject
to the given list.<S extends StateObject>
SaddItem
(S item) Adds the givenStateObject
as a child of this one.void
addItems
(List<? extends StateObject> items) Adds the given list ofStateObjects
as children of this one.void
addListChangeListener
(String listName, IListChangeListener<StateObject> listener) Registers the givenIListChangeListener
for the specified list.protected boolean
areChildrenEquivalent
(CoalesceExpressionStateObject stateObject) Determines whether the children of thisStateObject
are equivalent to the children of the given one, i.e.boolean
canMoveDown
(StateObject item) Determines whether the givenStateObject
can be moved down by one position in the list owned by its parent.boolean
canMoveUp
(StateObject item) Determines whether the givenStateObject
can be moved up by one position in the list owned by its parent.Returns the actual parsed object if thisStateObject
representation of the JPQL query was created by parsing an existing JPQL query.Returns the JPQL identifier of the expression represented by thisAbstractSingleEncapsulatedExpressionStateObject
.getItem
(int index) Returns theStateObject
at the given positions from the listboolean
hasItems()
Determines whether thisStateObject
has any children.protected void
Initializes this state object.boolean
isEquivalent
(StateObject stateObject) Determines whether the givenStateObject
is equivalent to this one, i.e.items()
Returns anListIterable
over the children.int
Returns the number of children this list holder has.moveDown
(StateObject item) Moves the givenStateObject
down by one position in the list owned by its parent.moveUp
(StateObject item) Moves the givenStateObject
up by one position in the list owned by its parent.void
Parses the given JPQL fragment, which represents a single encapsulated expression, and creates theStateObject
.protected void
parseItemInternal
(String... items) Parses the given list of JPQL fragments, which represents each of the encapsulated expressions, and creates theStateObjects
.void
parseItems
(String... items) Parses the given JPQL fragments, which represent individual expression, and creates theStateObjects
.void
parseItems
(ListIterator<String> items) Parses the given JPQL fragments, which represent individual expression, and creates theStateObjects
.void
removeItem
(StateObject item) Removes the givenStateObject
from the list of children.void
removeItems
(Collection<StateObject> items) Removes the givenStateObject
from the list of children.void
removeListChangeListener
(String listName, IListChangeListener<StateObject> listener) Unregisters the givenIListChangeListener
that was registered for the specified list.void
setExpression
(CoalesceExpression expression) Keeps a reference of theparsed object
object, which should only be done when this object is instantiated during the conversion of a parsed JPQL query intoStateObjects
.protected void
Prints out a string representation of this encapsulated information, which should not be used to define atrue
string representation of a JPQL query but should be used for debugging purposes.Methods inherited from class org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractEncapsulatedExpressionStateObject
toTextInternal
Methods inherited from class org.eclipse.persistence.jpa.jpql.tools.model.query.AbstractStateObject
acceptUnknownVisitor, acceptUnknownVisitor, addProblems, addPropertyChangeListener, areEquivalent, buildProblem, buildProblem, buildStateObject, buildStateObjects, checkParent, children, decorate, equals, findIdentificationVariable, firePropertyChanged, getChangeSupport, getDeclaration, getDecorator, getGrammar, getManagedTypeProvider, getParent, getQueryBuilder, getRoot, getType, getType, getTypeHelper, getTypeRepository, hashCode, isDecorated, parent, parent, parent, removePropertyChangeListener, setExpression, setParent, toString, toString, toStringInternal, toStringItems, toText
Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
Methods inherited from interface org.eclipse.persistence.jpa.jpql.tools.model.query.StateObject
addPropertyChangeListener, children, decorate, findIdentificationVariable, getDeclaration, getDecorator, getGrammar, getManagedTypeProvider, getParent, getQueryBuilder, getRoot, isDecorated, removePropertyChangeListener, setParent, toString, toText
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Field Details
-
STATE_OBJECTS_LIST
Notifies the content of the state object list has changed.- See Also:
-
-
Constructor Details
-
CoalesceExpressionStateObject
Creates a newCoalesceExpressionStateObject
.- Parameters:
parent
- The parent of this state object, which cannot benull
- Throws:
NullPointerException
- The given parent cannot benull
-
CoalesceExpressionStateObject
Creates a newCoalesceExpressionStateObject
.- Parameters:
parent
- The parent of this state object, which cannot benull
items
- The list ofStateObjects
representing the encapsulated expressions- Throws:
NullPointerException
- The given parent cannot benull
-
CoalesceExpressionStateObject
Creates a newCoalesceExpressionStateObject
.- Parameters:
parent
- The parent of this state object, which cannot benull
items
- The list ofStateObjects
representing the encapsulated expressions- Throws:
NullPointerException
- The given parent cannot benull
-
CoalesceExpressionStateObject
Creates a newCoalesceExpressionStateObject
.- Parameters:
parent
- The parent of this state object, which cannot benull
items
- The list of expression to parse into theirStateObject
- Throws:
NullPointerException
- The given parent cannot benull
-
-
Method Details
-
accept
Description copied from interface:StateObject
Visits thisStateObject
by the givenvisitor
.- Specified by:
accept
in interfaceStateObject
- Parameters:
visitor
- Thevisitor
to visit this object
-
addChildren
Description copied from class:AbstractStateObject
Adds the children of thisStateObject
to the given list.- Overrides:
addChildren
in classAbstractStateObject
- Parameters:
children
- The list used to store the children
-
addItem
Description copied from interface:ListHolderStateObject
Adds the givenStateObject
as a child of this one.- Specified by:
addItem
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- The childStateObject
to become a child of this one return The given item
-
addItems
Description copied from interface:ListHolderStateObject
Adds the given list ofStateObjects
as children of this one.- Specified by:
addItems
in interfaceListHolderStateObject<StateObject>
- Parameters:
items
- TheStateObjects
to become children of this one
-
addListChangeListener
Description copied from interface:ListHolderStateObject
Registers the givenIListChangeListener
for the specified list. The listener will be notified only when items are added, removed, moved from the list.- Specified by:
addListChangeListener
in interfaceListHolderStateObject<StateObject>
- Parameters:
listName
- The name of the list for which the listener will be notified when the content of the list has changedlistener
- The listener to be notified upon changes
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areChildrenEquivalent
Determines whether the children of thisStateObject
are equivalent to the children of the given one, i.e. the information of theStateObjects
is the same.- Parameters:
stateObject
- TheStateObject
to compare its children to this one's children- Returns:
true
if both have equivalent children;false
otherwise
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canMoveDown
Description copied from interface:ListHolderStateObject
Determines whether the givenStateObject
can be moved down by one position in the list owned by its parent.- Specified by:
canMoveDown
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- TheStateObject
that could potentially be moved down- Returns:
true
if the object can be moved down by one unit;false
otherwise
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canMoveUp
Description copied from interface:ListHolderStateObject
Determines whether the givenStateObject
can be moved up by one position in the list owned by its parent.- Specified by:
canMoveUp
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- TheStateObject
that could potentially be moved up- Returns:
true
if the object can be moved up by one unit;false
otherwise
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getExpression
Description copied from interface:StateObject
Returns the actual parsed object if thisStateObject
representation of the JPQL query was created by parsing an existing JPQL query.- Specified by:
getExpression
in interfaceStateObject
- Overrides:
getExpression
in classAbstractEncapsulatedExpressionStateObject
- Returns:
- The parsed object when a JPQL query is parsed and converted into a
StateObject
ornull
when the JPQL query is manually created (i.e. not from a string)
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getIdentifier
Description copied from class:AbstractEncapsulatedExpressionStateObject
Returns the JPQL identifier of the expression represented by thisAbstractSingleEncapsulatedExpressionStateObject
.- Specified by:
getIdentifier
in classAbstractEncapsulatedExpressionStateObject
- Returns:
- The JPQL identifier that is shown before the left parenthesis
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getItem
Description copied from interface:ListHolderStateObject
Returns theStateObject
at the given positions from the list- Specified by:
getItem
in interfaceListHolderStateObject<StateObject>
- Parameters:
index
- The position of theStateObject
to retrieve- Returns:
- The
StateObject
at the given position
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hasItems
public boolean hasItems()Description copied from interface:ListHolderStateObject
Determines whether thisStateObject
has any children.- Specified by:
hasItems
in interfaceListHolderStateObject<StateObject>
- Returns:
true
if thisStateObject
has children;false
otherwise
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initialize
protected void initialize()Description copied from class:AbstractStateObject
Initializes this state object.- Overrides:
initialize
in classAbstractStateObject
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isEquivalent
Description copied from interface:StateObject
Determines whether the givenStateObject
is equivalent to this one, i.e. the information of bothStateObject
is the same.- Specified by:
isEquivalent
in interfaceStateObject
- Overrides:
isEquivalent
in classAbstractStateObject
- Parameters:
stateObject
- TheStateObject
to compare its content to this one- Returns:
true
if both object are equivalent;false
otherwise
-
items
Description copied from interface:ListHolderStateObject
Returns anListIterable
over the children.- Specified by:
items
in interfaceListHolderStateObject<StateObject>
- Returns:
- An
ListIterable
that is iterating over the children
-
itemsSize
public int itemsSize()Description copied from interface:ListHolderStateObject
Returns the number of children this list holder has.- Specified by:
itemsSize
in interfaceListHolderStateObject<StateObject>
- Returns:
- The count of
StateObjects
that are children of this one
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moveDown
Description copied from interface:ListHolderStateObject
Moves the givenStateObject
down by one position in the list owned by its parent.- Specified by:
moveDown
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- TheStateObject
to move down in the list- Returns:
- The given item
-
moveUp
Description copied from interface:ListHolderStateObject
Moves the givenStateObject
up by one position in the list owned by its parent.- Specified by:
moveUp
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- TheStateObject
to move up in the list- Returns:
- The given item
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parseItem
Parses the given JPQL fragment, which represents a single encapsulated expression, and creates theStateObject
.- Parameters:
jpqlFragment
- The portion of the query representing a single encapsulated expression
-
parseItemInternal
Parses the given list of JPQL fragments, which represents each of the encapsulated expressions, and creates theStateObjects
.- Parameters:
items
- The list of expression to parse into theirStateObject
-
parseItems
Parses the given JPQL fragments, which represent individual expression, and creates theStateObjects
.- Parameters:
items
- The portion of the query representing a single encapsulated expression
-
parseItems
Parses the given JPQL fragments, which represent individual expression, and creates theStateObjects
.- Parameters:
items
- The portion of the query representing a single encapsulated expression
-
removeItem
Description copied from interface:ListHolderStateObject
Removes the givenStateObject
from the list of children.- Specified by:
removeItem
in interfaceListHolderStateObject<StateObject>
- Parameters:
item
- The childStateObject
to not longer be a child
-
removeItems
Description copied from interface:ListHolderStateObject
Removes the givenStateObject
from the list of children.- Specified by:
removeItems
in interfaceListHolderStateObject<StateObject>
- Parameters:
items
- TheStateObjects
to remove from this one
-
removeListChangeListener
Description copied from interface:ListHolderStateObject
Unregisters the givenIListChangeListener
that was registered for the specified list. The listener will no longer be notified only when items are added, removed, moved from the list.- Specified by:
removeListChangeListener
in interfaceListHolderStateObject<StateObject>
- Parameters:
listName
- The name of the list for which the listener was registeredlistener
- The listener to unregister
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setExpression
Keeps a reference of theparsed object
object, which should only be done when this object is instantiated during the conversion of a parsed JPQL query intoStateObjects
.- Parameters:
expression
- Theparsed object
representing aCASE
expression
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toTextEncapsulatedExpression
Description copied from class:AbstractEncapsulatedExpressionStateObject
Prints out a string representation of this encapsulated information, which should not be used to define atrue
string representation of a JPQL query but should be used for debugging purposes.- Specified by:
toTextEncapsulatedExpression
in classAbstractEncapsulatedExpressionStateObject
- Parameters:
writer
- The writer used to print out the string representation of the encapsulated information- Throws:
IOException
- This should never happens, only required becauseAppendable
is used instead ofStringBuilder
for instance
-