public class ExpressionRegistry
extends java.lang.Object
JPQLGrammar
given to JPQLExpression
will give access to this registry.
Provisional API: This interface is part of an interim API that is still under development and expected to change significantly before reaching stability. It is available at this early stage to solicit feedback from pioneering adopters on the understanding that any code that uses this API will almost certainly be broken (repeatedly) as the API evolves.
JPQLGrammar
,
ExpressionFactory
,
JPQLQueryBNF
Constructor and Description |
---|
ExpressionRegistry()
Creates the only instance of
ExpressionRegistry . |
Modifier and Type | Method and Description |
---|---|
void |
addChildBNF(java.lang.String queryBNFId,
java.lang.String childQueryBNFId)
Adds to the given query BNF a child BNF.
|
void |
addChildFactory(java.lang.String queryBNFId,
java.lang.String childExpressionFactoryId)
Adds to the given unique identifier of an
ExpressionFactory to the given query BNF. |
void |
addIdentifier(java.lang.String expressionFactoryId,
java.lang.String identifier)
Adds the given JPQL identifier to this factory.
|
void |
addIdentifiers(java.lang.String expressionFactoryId,
java.lang.String... identifiers)
Adds the given JPQL identifiers to this factory.
|
ExpressionFactory |
expressionFactoryForIdentifier(java.lang.String identifier)
Retrieves the
ExpressionFactory that is responsible for creating the Expression
object that represents the given JPQL identifier. |
ExpressionFactory |
getExpressionFactory(java.lang.String expressionFactoryId)
Retrieves the registered
ExpressionFactory that was registered for the given unique identifier. |
IdentifierRole |
getIdentifierRole(java.lang.String identifier)
Retrieves the
IdentifierRole of the given JPQL identifier. |
java.util.Set<java.lang.String> |
getIdentifiers()
Returns the JPQL identifiers that are supported by the
JPQL grammar . |
java.lang.Iterable<java.lang.String> |
getIdentifiers(java.lang.String queryBNFId)
Retrieves the JPQL identifiers that are supported by the BNF rule with the given unique
identifier.
|
JPAVersion |
getIdentifierVersion(java.lang.String identifier)
Retrieves the JPA version in which the identifier was first introduced.
|
JPQLQueryBNF |
getQueryBNF(java.lang.String queryBNFId)
Retrieves the BNF object that was registered for the given unique identifier.
|
protected void |
initialize()
Instantiates the only instance of various API used by the parser.
|
boolean |
isIdentifier(java.lang.String text)
Determines if the given word is a JPQL identifier.
|
void |
registerBNF(JPQLQueryBNF queryBNF)
Registers the given
JPQLQueryBNF . |
void |
registerFactory(ExpressionFactory expressionFactory)
Registers the given
ExpressionFactory by storing it for all its identifiers. |
void |
registerIdentifierRole(java.lang.String identifier,
IdentifierRole role)
Registers the
IdentifierRole for the given JPQL identifier. |
void |
registerIdentifierVersion(java.lang.String identifier,
JPAVersion version)
Registers the
JPAVersion for which the given JPQL identifier was defined. |
void |
setFallbackBNFId(java.lang.String queryBNFId,
java.lang.String fallbackBNFId)
When parsing the query and no
JPQLQueryBNFs can help to parse the query,
then it will fall back on the given one. |
void |
setFallbackExpressionFactoryId(java.lang.String queryBNFId,
java.lang.String fallbackExpressionFactoryId)
Sets the unique identifier of the
ExpressionFactory to use when the fall back BNF
ID is not null . |
void |
setHandleCollection(java.lang.String queryBNFId,
boolean handleCollection)
Determines whether the
Expression handles a collection of sub-expressions that
are separated by commas. |
void |
setHandleNestedArray(java.lang.String queryBNFId,
boolean handleNestedArray)
Sets whether the BNF with the given ID supports nested array or not.
|
void |
setHandleSubExpression(java.lang.String queryBNFId,
boolean handleSubExpression)
Sets whether the query BNF with the given ID handles parsing a sub-expression, i.e. parsing an
expression encapsulated by parenthesis.
|
void |
unregisterBNF(JPQLQueryBNF queryBNF)
Unregisters the given
JPQLQueryBNF . |
public ExpressionRegistry()
ExpressionRegistry
.public void addChildBNF(java.lang.String queryBNFId, java.lang.String childQueryBNFId)
queryBNFId
- The unique identifier of the parent BNF to add a child BNFchildQueryBNFId
- The unique identifier of the child to add to the parent BNFjava.lang.NullPointerException
- The JPQLQueryBNF
identified by the given ID does not existpublic void addChildFactory(java.lang.String queryBNFId, java.lang.String childExpressionFactoryId)
ExpressionFactory
to the given query BNF.queryBNFId
- The unique identifier of the parent BNFchildExpressionFactoryId
- The unique identifier of the ExpressionFactory
to add
to the given query BNFjava.lang.NullPointerException
- The JPQLQueryBNF
identified by the given ID does not existpublic void addIdentifier(java.lang.String expressionFactoryId, java.lang.String identifier)
expressionFactoryId
- The unique identifier of the ExpressionFactory
to add more
JPQL identifiersidentifier
- The JPQL identifier this factory will parsepublic void addIdentifiers(java.lang.String expressionFactoryId, java.lang.String... identifiers)
expressionFactoryId
- The unique identifier of the ExpressionFactory
to add more
JPQL identifiersidentifiers
- The JPQL identifiers this factory will parsepublic ExpressionFactory expressionFactoryForIdentifier(java.lang.String identifier)
ExpressionFactory
that is responsible for creating the Expression
object that represents the given JPQL identifier.identifier
- The JPQL identifier for which its factory is searchedExpressionFactory
that creates the Expression
or
null
if none was foundpublic ExpressionFactory getExpressionFactory(java.lang.String expressionFactoryId)
ExpressionFactory
that was registered for the given unique identifier.expressionFactoryId
- The unique identifier of the ExpressionFactory
to retrieveExpressionFactory
mapped with the given unique identifierpublic IdentifierRole getIdentifierRole(java.lang.String identifier)
IdentifierRole
of the given JPQL identifier. A role helps to describe
the purpose of the identifier in a JPQL query.identifier
- The JPQL identifier for which its role is returnedIdentifierRole
of the given JPQL identifierpublic java.util.Set<java.lang.String> getIdentifiers()
JPQL grammar
.public java.lang.Iterable<java.lang.String> getIdentifiers(java.lang.String queryBNFId)
ExpressionFactory
registered with the BNF rule and its child BNF rules.public JPAVersion getIdentifierVersion(java.lang.String identifier)
public JPQLQueryBNF getQueryBNF(java.lang.String queryBNFId)
queryBNFId
- The unique identifier of the JPQLQueryBNF
to retrieveJPQLQueryBNF
representing a section of the grammarprotected void initialize()
public boolean isIdentifier(java.lang.String text)
text
- The string value to test if it's a JPQL identifier based on what is registered
with this ExpressionRegistry
true
if the word is an identifier, false
otherwisepublic void registerBNF(JPQLQueryBNF queryBNF)
JPQLQueryBNF
. The BNF will be registered using its unique
identifier.queryBNF
- The JPQLQueryBNF
to storejava.lang.NullPointerException
- The JPQLQueryBNF
cannot be null
public void registerFactory(ExpressionFactory expressionFactory)
ExpressionFactory
by storing it for all its identifiers.expressionFactory
- The ExpressionFactory
to storejava.lang.NullPointerException
- The ExpressionFactory
cannot be null
public void registerIdentifierRole(java.lang.String identifier, IdentifierRole role)
IdentifierRole
for the given JPQL identifier.identifier
- The JPQL identifier to register its role within a JPQL queryrole
- The role of the given JPQL identifierjava.lang.NullPointerException
- The JPQL identifier and the cannot be
null
public void registerIdentifierVersion(java.lang.String identifier, JPAVersion version)
JPAVersion
for which the given JPQL identifier was defined.identifier
- The JPQL identifier to register in which version it was added to the grammarversion
- The version when the JPQL identifier was added to the grammarjava.lang.NullPointerException
- The JPQL identifier and the JPAVersion
cannot be
null
public void setFallbackBNFId(java.lang.String queryBNFId, java.lang.String fallbackBNFId)
JPQLQueryBNFs
can help to parse the query,
then it will fall back on the given one.queryBNFId
- The unique identifier of the BNF to modify its fallback BNF unique identifierfallbackBNFId
- The unique identifier of the JPQLQueryBNF
to use in the last resortjava.lang.NullPointerException
- The JPQLQueryBNF
identified by the given ID does not existpublic void setFallbackExpressionFactoryId(java.lang.String queryBNFId, java.lang.String fallbackExpressionFactoryId)
ExpressionFactory
to use when the fall back BNF
ID is not null
. This will be used to parse a portion of the query when the
registered expression factories
cannot parse it.
Note: This method is only called if JPQLQueryBNF.
getFallbackBNFId()
does not return null
.
queryBNFId
- The unique identifier of the BNF to modify its fallback expression factory
unique identifierjava.lang.NullPointerException
- The JPQLQueryBNF
identified by the given ID does not existpublic void setHandleCollection(java.lang.String queryBNFId, boolean handleCollection)
Expression
handles a collection of sub-expressions that
are separated by commas.queryBNF
- The unique identifier of the JPQLQueryBNF
handleCollection
- true
if the sub-expression to parse might have several
sub-expressions separated by commas; false
otherwisepublic void setHandleNestedArray(java.lang.String queryBNFId, boolean handleNestedArray)
queryBNFId
- The unique identifier of the JPQLQueryBNF
handleNestedArray
- true
if the expression represented by this BNF can be
a nested array; false
otherwisepublic void setHandleSubExpression(java.lang.String queryBNFId, boolean handleSubExpression)
ExpressionFactory
. The default behavior is to not handle it.
A good example for using this option is when an Expression
cannot use any ExpressionFactory
for creating a child object, parsing will use the fallback ExpressionFactory
, if one was specified. So when this is set to true
, the
fallback ExpressionFactory
will be immediately invoked.
Let's say we want to parse "SELECT e FROM (SELECT a FROM Address a) e", FromClause
cannot use a factory for parsing the entity name (that's what usually the FROM
clause has) so it uses the fallback factory to create IdentificationVariableDeclaration
.
Then IdentificationVariableDeclaration
also cannot use any factory to create its
child object so it uses the fallback factory to create RangeVariableDeclaration
.
By changing the status of for handling the sub-expression for the BNFs for those objects, then
a subquery can be created by RangeVariableDeclaration
.
FromClause
|- IdentificationVariableDeclaration
|- RangeVariableDeclaration
|- SubExpression(subquery)
In order to get this working, the following would have to be done into the grammar:
public class MyJPQLGrammar extends AbstractJPQLGrammar {
@Override
protected void initializeBNFs() {
setHandleSubExpression(InternalFromClauseBNF.ID, true);
setHandleSubExpression(InternalSimpleFromClauseBNF.ID, true);
setHandleSubExpression(IdentificationVariableDeclarationBNF.ID, true);
setHandleSubExpression(RangeVariableDeclarationBNF.ID, true);
}
}
queryBNFId
- The unique identifier of the JPQLQueryBNF
handleSubExpression
- true
to let the creation of a sub-expression be
created by the fallback ExpressionFactory
registered with this BNF; false
otherwise (which is the default value)public void unregisterBNF(JPQLQueryBNF queryBNF)
JPQLQueryBNF
.queryBNF
- The JPQLQueryBNF
to unregisterjava.lang.NullPointerException
- The JPQLQueryBNF
cannot be null