org.apache.openjpa.kernel.jpql
Class JPQLExpressionBuilder

java.lang.Object
  org.apache.openjpa.kernel.exps.AbstractExpressionBuilder
      org.apache.openjpa.kernel.jpql.JPQLExpressionBuilder

All Implemented Interfaces:

org.apache.openjpa.kernel.jpql.JPQLTreeConstants

public class JPQLExpressionBuilder
extends AbstractExpressionBuilder
implements org.apache.openjpa.kernel.jpql.JPQLTreeConstants

Builder for JPQL expressions. This class takes the query parsed in JPQLExpressionBuilder.ParsedJPQL and converts it to an expression tree using an ExpressionFactory. Public for unit testing purposes.

Author:

Marc Prud'hommeaux, Patrick Linskey

Nested Class Summary

protected static class	JPQLExpressionBuilder.JPQLNode Base node that will be generated by the JPQLExpressionBuilder; base class of the SimpleNode that is used by JPQLExpressionBuilder.ParsedJPQL.
static class	JPQLExpressionBuilder.ParsedJPQL Public for unit testing purposes.

Field Summary

Fields inherited from class org.apache.openjpa.kernel.exps.AbstractExpressionBuilder

CONTAINS_TYPE_ELEMENT, CONTAINS_TYPE_KEY, CONTAINS_TYPE_VALUE, EX_FATAL, EX_UNSUPPORTED, EX_USER, factory, resolver, TYPE_CHAR_OBJ, TYPE_COLLECTION, TYPE_MAP, TYPE_NUMBER, TYPE_OBJECT, TYPE_STRING

Fields inherited from interface org.apache.openjpa.kernel.jpql.JPQLTreeConstants

JJTABS, JJTABSTRACTSCHEMANAME, JJTADD, JJTAGGREGATE, JJTALL, JJTAND, JJTANY, JJTASCENDING, JJTAVERAGE, JJTBETWEEN, JJTBOOLEANLITERAL, JJTCASE, JJTCLASSNAME, JJTCOALESCE, JJTCOLLECTIONPARAMETER, JJTCONCAT, JJTCONSTRUCTOR, JJTCONSTRUCTORPARAM, JJTCONSTRUCTORPARAMS, JJTCOUNT, JJTCURRENTDATE, JJTCURRENTTIME, JJTCURRENTTIMESTAMP, JJTDATELITERAL, JJTDECIMALLITERAL, JJTDELETE, JJTDESCENDING, JJTDISTINCT, JJTDISTINCTPATH, JJTDIVIDE, JJTENTRY, JJTEQUALS, JJTESCAPECHARACTER, JJTEXISTS, JJTFROM, JJTFROMITEM, JJTGENERALCASE, JJTGENERALIDENTIFIER, JJTGREATEROREQUAL, JJTGREATERTHAN, JJTGROUPBY, JJTGROUPBYEXTENSION, JJTHAVING, JJTIDENTIFICATIONVARIABLE, JJTIDENTIFIER, JJTIN, JJTINDEX, JJTINNERFETCHJOIN, JJTINNERJOIN, JJTINTEGERLITERAL, JJTISEMPTY, JJTISNULL, JJTKEY, JJTLENGTH, JJTLESSOREQUAL, JJTLESSTHAN, JJTLIKE, JJTLOCATE, JJTLOWER, JJTMAX, JJTMEMBEROF, JJTMIN, JJTMOD, JJTMULTIPLY, JJTNAMEDINPUTPARAMETER, JJTNEGATIVE, jjtNodeName, JJTNOT, JJTNOTEQUALS, JJTNULLIF, JJTOR, JJTORDERBY, JJTORDERBYEXTENSION, JJTORDERBYITEM, JJTOUTERFETCHJOIN, JJTOUTERJOIN, JJTPATH, JJTPATTERNVALUE, JJTPOSITIONALINPUTPARAMETER, JJTQUALIFIEDIDENTIFIER, JJTQUALIFIEDPATH, JJTSCALAREXPRESSION, JJTSELECT, JJTSELECTCLAUSE, JJTSELECTEXPRESSION, JJTSELECTEXPRESSIONS, JJTSELECTEXTENSION, JJTSIMPLECASE, JJTSIZE, JJTSQRT, JJTSTRINGLITERAL, JJTSTRINGLITERAL2, JJTSUBSELECT, JJTSUBSTRING, JJTSUBTRACT, JJTSUM, JJTTIMELITERAL, JJTTIMESTAMPLITERAL, JJTTOK, JJTTRIM, JJTTRIMBOTH, JJTTRIMCHARACTER, JJTTRIMLEADING, JJTTRIMTRAILING, JJTTYPE, JJTTYPELITERAL, JJTUPDATE, JJTUPDATEITEM, JJTUPDATEVALUE, JJTUPPER, JJTVALUE, JJTVOID, JJTWHEN, JJTWHENSCALAR, JJTWHERE

Constructor Summary

JPQLExpressionBuilder(ExpressionFactory factory, ExpressionStoreQuery query, Object parsedQuery)
Constructor.

Method Summary

protected void	addSchemaToContext(String id, ClassMetaData meta) Register the schema alias to the current JPQL query context.
protected void	addVariableToContext(String id, Value var) Register the variable associated with the schema alias (id) to the current JPQL query context.
static void	checkEmbeddable(Value val, String currentQuery)
static Value	convertSubstringArguments(ExpressionFactory factory, Value val1, Value val2, Value val3) Converts JPQL substring() function to OpenJPA ExpressionFactory substring() arguments.
protected String	currentQuery() Returns the current string being parsed; used for error messages.
protected Expression	evalFetchJoins(QueryExpressions exps)
protected void	evalSetClause(QueryExpressions exps)
protected ClassMetaData	getCandidateMetaData(JPQLExpressionBuilder.JPQLNode node)
protected ClassLoader	getClassLoader() Returns the class loader that should be used for resolving class names (in addition to the resolver in the query).
protected Class<?>	getDeclaredVariableType(String name) Returns the type of the named variable if it has been declared.
protected Value	getDefinedVariable(String id)
protected Localizer	getLocalizer() Used for obtaining the Localizer to use for translating error messages.
protected JPQLExpressionBuilder.ParsedJPQL	getParsedQuery()
protected JPQLExpressionBuilder.ParsedJPQL	getParsedQuery(String jpql)
(package private) QueryExpressions	getQueryExpressions()
protected Value	getVariable(String var) Returns the variable associated with the schema alias (id).
protected Value	getVariable(String id, boolean bind) Identification variables in JPQL are case insensitive, so lower-case all variables we are going to bind.
protected boolean	isDeclaredVariable(String name) Returns whether the specified variable name has been explicitly declared.
(package private) boolean	isPath(JPQLExpressionBuilder.JPQLNode node) Check to see if the specific node is a path (vs.
protected boolean	isSeenVariable(String var) Return whether the given id has been used as a variable.
protected ClassMetaData	resolveClassMetaData(JPQLExpressionBuilder.JPQLNode node)
void	setImplicitTypes(Value val1, Value val2, Class<?> expected) Set the implicit types of the given values based on the fact that they're used together, and based on the operator type.
static void	setImplicitTypes(Value val1, Value val2, Class<?> expected, Resolver resolver, OrderedMap<Object,Class<?>> parameterTypes, String currentQuery)

Methods inherited from class org.apache.openjpa.kernel.exps.AbstractExpressionBuilder

addAccessPath, assertUnboundVariablesValid, bind, convertTypes, convertTypesQuotedNumbers, createVariable, getAccessPath, getMetaData, getMetaData, isBound, isNumeric, parseException, setImplicitContainsTypes, setImplicitType, setImplicitTypes, traversePath, traversePath, traverseStaticField, traverseXPath

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.openjpa.kernel.jpql.JPQLTreeConstants

Constructor Detail

JPQLExpressionBuilder

public JPQLExpressionBuilder(ExpressionFactory factory,
                             ExpressionStoreQuery query,
                             Object parsedQuery)

Constructor.

Parameters:

factory - the expression factory to use

query - used to resolve variables, parameters, and class names used in the query

parsedQuery - the parsed query

Method Detail

getLocalizer

protected Localizer getLocalizer()

Description copied from class: AbstractExpressionBuilder

Used for obtaining the Localizer to use for translating error messages.

Specified by:

getLocalizer in class AbstractExpressionBuilder

getClassLoader

protected ClassLoader getClassLoader()

Description copied from class: AbstractExpressionBuilder

Returns the class loader that should be used for resolving class names (in addition to the resolver in the query).

Specified by:

getClassLoader in class AbstractExpressionBuilder

getParsedQuery

protected JPQLExpressionBuilder.ParsedJPQL getParsedQuery()

getParsedQuery

protected JPQLExpressionBuilder.ParsedJPQL getParsedQuery(String jpql)

resolveClassMetaData

protected ClassMetaData resolveClassMetaData(JPQLExpressionBuilder.JPQLNode node)

getCandidateMetaData

protected ClassMetaData getCandidateMetaData(JPQLExpressionBuilder.JPQLNode node)

currentQuery

protected String currentQuery()

Description copied from class: AbstractExpressionBuilder

Returns the current string being parsed; used for error messages.

Specified by:

currentQuery in class AbstractExpressionBuilder

getQueryExpressions

QueryExpressions getQueryExpressions()

evalFetchJoins

protected Expression evalFetchJoins(QueryExpressions exps)

evalSetClause

protected void evalSetClause(QueryExpressions exps)

isDeclaredVariable

protected boolean isDeclaredVariable(String name)

Description copied from class: AbstractExpressionBuilder

Returns whether the specified variable name has been explicitly declared. Note all query languages necessarily support declaring variables.

Specified by:

isDeclaredVariable in class AbstractExpressionBuilder

Parameters:

name - the variable to check

Returns:

true if the variabe has been explicitely declared

isPath

boolean isPath(JPQLExpressionBuilder.JPQLNode node)

Check to see if the specific node is a path (vs. a schema name)

getVariable

protected Value getVariable(String id,
                            boolean bind)

Identification variables in JPQL are case insensitive, so lower-case all variables we are going to bind.

Overrides:

getVariable in class AbstractExpressionBuilder

getDefinedVariable

protected Value getDefinedVariable(String id)

isSeenVariable

protected boolean isSeenVariable(String var)

Description copied from class: AbstractExpressionBuilder

Return whether the given id has been used as a variable.

Overrides:

isSeenVariable in class AbstractExpressionBuilder

checkEmbeddable

public static void checkEmbeddable(Value val,
                                   String currentQuery)

convertSubstringArguments

public static Value convertSubstringArguments(ExpressionFactory factory,
                                              Value val1,
                                              Value val2,
                                              Value val3)

Converts JPQL substring() function to OpenJPA ExpressionFactory substring() arguments. The semantics of the JPQL substring() function are that arg2 is the 1-based start index, and arg3 is the length of the string to be return. This is different than the semantics of the ExpressionFactory's substring(), which matches the Java language (0-based start index, arg2 is the end index): we perform the translation by adding one to the first argument, and then adding the first argument to the second argument to get the endIndex.

Parameters:

val1 - the original String

val2 - the 1-based start index as per JPQL substring() semantics

val3 - the length of the returned string as per JPQL semantics

setImplicitTypes

public void setImplicitTypes(Value val1,
                             Value val2,
                             Class<?> expected)

Description copied from class: AbstractExpressionBuilder

Set the implicit types of the given values based on the fact that they're used together, and based on the operator type.

Overrides:

setImplicitTypes in class AbstractExpressionBuilder

setImplicitTypes

public static void setImplicitTypes(Value val1,
                                    Value val2,
                                    Class<?> expected,
                                    Resolver resolver,
                                    OrderedMap<Object,Class<?>> parameterTypes,
                                    String currentQuery)

getDeclaredVariableType

protected Class<?> getDeclaredVariableType(String name)

Description copied from class: AbstractExpressionBuilder

Returns the type of the named variable if it has been declared.

Specified by:

getDeclaredVariableType in class AbstractExpressionBuilder

addSchemaToContext

protected void addSchemaToContext(String id,
                                  ClassMetaData meta)

Description copied from class: AbstractExpressionBuilder

Register the schema alias to the current JPQL query context.

Specified by:

addSchemaToContext in class AbstractExpressionBuilder

addVariableToContext

protected void addVariableToContext(String id,
                                    Value var)

Description copied from class: AbstractExpressionBuilder

Register the variable associated with the schema alias (id) to the current JPQL query context.

Specified by:

addVariableToContext in class AbstractExpressionBuilder

getVariable

protected Value getVariable(String var)

Description copied from class: AbstractExpressionBuilder

Returns the variable associated with the schema alias (id).

Specified by:

getVariable in class AbstractExpressionBuilder

Returns: