/*******************************************************************************
* Copyright (c) 2006, 2013 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* Oracle - initial API and implementation
*
******************************************************************************/
package org.eclipse.persistence.internal.jpa.jpql;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.security.AccessController;
import java.security.PrivilegedActionException;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.eclipse.persistence.descriptors.ClassDescriptor;
import org.eclipse.persistence.expressions.Expression;
import org.eclipse.persistence.internal.security.PrivilegedAccessHelper;
import org.eclipse.persistence.internal.security.PrivilegedClassForName;
import org.eclipse.persistence.internal.security.PrivilegedGetConstructorFor;
import org.eclipse.persistence.internal.security.PrivilegedInvokeConstructor;
import org.eclipse.persistence.internal.sessions.AbstractSession;
import org.eclipse.persistence.jpa.jpql.EclipseLinkLiteralVisitor;
import org.eclipse.persistence.jpa.jpql.ExpressionTools;
import org.eclipse.persistence.jpa.jpql.LiteralType;
import org.eclipse.persistence.jpa.jpql.LiteralVisitor;
import org.eclipse.persistence.jpa.jpql.parser.CollectionValuedPathExpression;
import org.eclipse.persistence.jpa.jpql.parser.InputParameter;
import org.eclipse.persistence.jpa.jpql.parser.JPQLExpression;
import org.eclipse.persistence.jpa.jpql.parser.JPQLGrammar;
import org.eclipse.persistence.jpa.jpql.parser.Join;
import org.eclipse.persistence.jpa.jpql.parser.SimpleSelectStatement;
import org.eclipse.persistence.jpa.jpql.parser.StateFieldPathExpression;
import org.eclipse.persistence.mappings.DatabaseMapping;
import org.eclipse.persistence.mappings.querykeys.QueryKey;
import org.eclipse.persistence.queries.DatabaseQuery;
import org.eclipse.persistence.queries.ReportQuery;
/**
* This context is used when creating and populating a {@link DatabaseQuery} when traversing the
* parsed representation of a JPQL query.
*
* @version 2.5
* @since 2.3
* @author Pascal Filion
* @author John Bracken
*/
@SuppressWarnings("nls")
final class JPQLQueryContext {
/**
* The current {@link JPQLQueryContext} is the context used for the current query or subquery.
* If the current context is not the global context, then its parent is non <code>null</code>.
*/
private JPQLQueryContext currentContext;
/**
* The parsed {@link Expression JPQL Expression} currently visited.
*/
private org.eclipse.persistence.jpa.jpql.parser.Expression currentQuery;
/**
* The resolver of the current query's declaration. For a <b>SELECT</b> query, it contains the
* information defined in the <b>FROM</b> clause. For <b>DELETE</b> and <b>UPDATE</b> queries,
* it contains a single range declaration variable.
*/
private DeclarationResolver declarationResolver;
/**
* The builder that can convert a {@link org.eclipse.persistence.jpa.jpql.parser.Expression JPQL
* Expression} into an {@link Expression EclipseLink Expression}.
*/
private ExpressionBuilderVisitor expressionBuilder;
/**
* The cached {@link Expression Expressions} mapped by a variable name.
*/
private Map<String, Expression> expressions;
/**
* The input parameter name mapped to its type. The input parameter name starts with the
* positional parameter ('?' or ':').
*/
Map<InputParameter, Expression> inputParameters;
/**
* The parsed representation of the JPQL query.
*/
private JPQLExpression jpqlExpression;
/**
* The JPQL grammar that defines how to parse a JPQL query.
*/
private JPQLGrammar jpqlGrammar;
/**
* The JPQL query to convert into an EclipseLink {@link Expression}.
*/
private CharSequence jpqlQuery;
/**
* This visitor is used to retrieve a variable name from various type of
* {@link org.eclipse.persistence.jpa.query.parser.Expression JPQL Expression}.
*/
private EclipseLinkLiteralVisitor literalVisitor;
/**
* This visitor is responsible to calculate the closest type of any input parameter.
*/
private ParameterTypeVisitor parameterTypeVisitor;
/**
* When this context is a sub-context used for a subquery, then this is the context for the
* parent query.
*/
private JPQLQueryContext parent;
/**
* The {@link DatabaseQuery} being populated by visiting the parsed tree representation of the
* JPQL query.
*/
private DatabaseQuery query;
/**
* The EclipseLink {@link AbstractSession} this context will use.
*/
private AbstractSession session;
/**
* This resolver is used to calculate the type of any {@link org.eclipse.persistence.jpa.jpql.
* parser.Expression JPQL Expression}.
*/
private TypeResolver typeResolver;
/**
* The types that have been cached for faster access.
*/
private Map<String, Class<?>> types;
/**
* The identification variables that were used in the current query.
*/
private Set<String> usedIdentificationVariables;
/**
* An empty array used when the type of an {@link org.eclipse.persistence.jpa.jpql.parser.
* Expression JPQL Expression} is not required.
*/
private static final Class<?>[] EMPTY_TYPE = new Class<?>[1];
/**
* Creates a new <code>JPQLQueryContext</code>.
*
* @param query The {@link DatabaseQuery} from which information will be queries
* @param jpqlGrammar The JPQL grammar that defines how the JPQL query was parsed
* @since 2.5
*/
JPQLQueryContext(DatabaseQuery query, JPQLGrammar jpqlGrammar) {
this(jpqlGrammar);
String jpqlQuery = query.getJPQLString();
cache(query.getSession(), query, parse(jpqlQuery), jpqlQuery);
}
/**
* Creates a new <code>JPQLQueryContext</code>.
*
* @param jpqlGrammar The JPQL grammar that defines how the JPQL query was parsed
*/
JPQLQueryContext(JPQLGrammar jpqlGrammar) {
super();
this.jpqlGrammar = jpqlGrammar;
this.currentContext = this;
}
/**
* Creates a new <code>JPQLQueryContext</code>.
*
* @param parent The parent of this context, which is never <code>null</code>
* @param currentQuery The parsed tree representation of the subquery
* @param query The {@link ReportQuery} that will be populated by visiting the parsed tree
* representation of the subquery
*/
private JPQLQueryContext(JPQLQueryContext parent,
org.eclipse.persistence.jpa.jpql.parser.Expression currentQuery,
ReportQuery query) {
this(parent.jpqlGrammar);
this.query = query;
this.parent = parent;
this.currentQuery = currentQuery;
}
/**
* Caches the given input parameter name with its calculated type.
*
* @param parameterName The name of the input parameter
* @param type The calculated type based on its surrounding, which is never <code>null</code>
*/
void addInputParameter(InputParameter inputParameter, Expression queryExpression) {
if (parent != null) {
parent.addInputParameter(inputParameter, queryExpression);
}
else {
if (inputParameters == null) {
inputParameters = new HashMap<InputParameter, Expression>();
}
inputParameters.put(inputParameter, queryExpression);
}
}
/**
* Caches the given query {@link Expression} for future use.
*
* @param variableName The identification variable name that is the key to store the given
* {@link Expression}
* @param expression The {@link Expression} that can be reused rather than being recreated
*/
void addQueryExpression(String variableName, Expression expression) {
currentContext.addQueryExpressionImp(variableName, expression);
}
/**
* Caches the given query {@link Expression} for future use.
*
* @param variableName The identification variable name that is the key to store the given
* {@link Expression}
* @param expression The {@link Expression} that can be reused rather than being recreated
*/
void addQueryExpressionImp(String variableName, Expression expression) {
if (expressions == null) {
expressions = new HashMap<String, Expression>();
}
expressions.put(variableName, expression);
}
/**
* Adds a virtual range variable declaration that will be used when a JPQL fragment is parsed.
*
* @param entityName The name of the entity to be accessible with the given variable name
* @param variableName The identification variable used to navigate to the entity
*/
void addRangeVariableDeclaration(String entityName, String variableName) {
// This method should only be used by HermesParser.buildSelectionCriteria()
declarationResolver = new DeclarationResolver(this, null);
declarationResolver.addRangeVariableDeclaration(
entityName,
variableName
);
}
/**
* Adds the given identification variable, which is done when it's used in a clause, except in
* the declaration portion of the query.
*
* @param variableName The identification variable that is used within a clause
*/
void addUsedIdentificationVariable(String variableName) {
currentContext.addUsedIdentificationVariableImp(variableName);
}
/**
* Adds the given identification variable, which is done when it's used in a clause, except in
* the declaration portion of the query.
*
* @param variableName The identification variable that is used within a clause
*/
void addUsedIdentificationVariableImp(String variableName) {
if (usedIdentificationVariables == null) {
usedIdentificationVariables = new HashSet<String>();
}
usedIdentificationVariables.add(variableName);
}
/**
* Retrieves the Java type for the given type name, which has to be the fully qualified type name.
*
* @param typeName The fully qualified type name
* @return The Java type if it could be retrieved; <code>null</code> otherwise
*/
@SuppressWarnings("unchecked")
private Class<?> attemptLoadType(String typeName) {
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()) {
try {
return (Class<?>) AccessController.doPrivileged(
new PrivilegedClassForName(typeName, true, getClassLoader())
);
}
catch (PrivilegedActionException exception) {
return null;
}
}
return PrivilegedAccessHelper.getClassForName(typeName, true, getClassLoader());
}
catch (ClassNotFoundException e) {
return null;
}
}
/**
* Converts the given {@link org.eclipse.persistence.jpa.jpql.parser.Expression JPQL Expression}
* into an {@link Expression}.
*
* @param expression The {@link org.eclipse.persistence.jpa.jpql.parser.Expression JPQL Expression}
* to visit and to convert into an {@link Expression}
* @return The {@link Expression} representing the given parsed expression
*/
Expression buildExpression(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
return expressionBuilder().buildExpression(expression, EMPTY_TYPE);
}
/**
* Converts the given {@link org.eclipse.persistence.jpa.jpql.parser.Expression JPQL Expression}
* into an {@link Expression}.
*
* @param expression The {@link org.eclipse.persistence.jpa.jpql.parser.Expression JPQL Expression}
* to visit and to convert into an {@link Expression}
* @param type The given array will be used to store the type of the given expression
* @return The {@link Expression} representing the given parsed expression
*/
Expression buildExpression(org.eclipse.persistence.jpa.jpql.parser.Expression expression,
Class<?>[] type) {
return expressionBuilder().buildExpression(expression, type);
}
/**
* Creates a new EclipseLink {@link Expression} by visiting the given JPQL {@link
* CollectionValuedPathExpression} that is used in the <code><b>GROUP BY</b></code> clause.
*
* @param expression The {@link CollectionValuedPathExpression} to convert into an EclipseLink
* {@link Expression}
* @return The EclipseLink {@link Expression} representation of that path expression
*/
Expression buildGroupByExpression(CollectionValuedPathExpression expression) {
return expressionBuilder().buildGroupByExpression(expression);
}
/**
* Creates a new EclipseLink {@link Expression} by visiting the given JPQL {@link
* StateFieldPathExpression}. This method temporarily changes the null allowed flag if the state
* field is a foreign reference mapping
*
* @param expression The {@link StateFieldPathExpression} to convert into an EclipseLink {@link
* Expression}
* @return The EclipseLink {@link Expression} representation of that path expression
*/
Expression buildModifiedPathExpression(StateFieldPathExpression expression) {
return expressionBuilder().buildModifiedPathExpression(expression);
}
/**
* Creates a new {@link ReportQuery} by visiting the given {@link SimpleSelectStatement}.
*
* @param expression The {@link SimpleSelectStatement} to convert into a {@link ReportQuery}
* @return A fully initialized {@link ReportQuery}
*/
ReportQuery buildSubquery(SimpleSelectStatement expression) {
return expressionBuilder().buildSubquery(expression);
}
/**
* Sets the given named query and string representation of the JPQL query.
*
* @param session The EclipseLink {@link AbstractSession} this context will use
* @param query The {@link DatabaseQuery} that may already exist and it will be populated with
* the information contained in the JPQL query or <code>null</code> if the query will need to be created
* @param jpqlExpression The parsed tree representation of the JPQL query
* @param jpqlQuery The JPQL query
*/
void cache(AbstractSession session,
DatabaseQuery query,
JPQLExpression jpqlExpression,
CharSequence jpqlQuery) {
this.query = query;
this.session = session;
this.jpqlQuery = jpqlQuery;
this.currentQuery = jpqlExpression;
this.jpqlExpression = jpqlExpression;
}
/**
* Returns the type of the given {@link DatabaseMapping}, which is the persistent field type.
*
* @param mapping The {@link DatabaseMapping} to retrieve its persistent field type
* @return The persistent field type
*/
Class<?> calculateMappingType(DatabaseMapping mapping) {
return typeResolver().calculateMappingType(mapping);
}
/**
* Returns the type of the given {@link QueryKey}, which is the persistent field type.
*
* @param queryKey The {@link QueryKey} to retrieve its persistent field type
* @return The persistent field type
*/
Class<?> calculateQueryKeyType(QueryKey queryKey) {
return typeResolver().calculateQueryKeyType(queryKey);
}
/**
* Disposes this context, which is the current context being used by a subquery. Once it is
* disposed, any information retrieved will be for the subquery's parent query.
*/
void disposeSubqueryContext() {
currentContext = currentContext.parent;
}
private ExpressionBuilderVisitor expressionBuilder() {
if (parent != null) {
return parent.expressionBuilder();
}
if (expressionBuilder == null) {
expressionBuilder = new ExpressionBuilderVisitor(this);
}
return expressionBuilder;
}
/**
* Retrieves the {@link Declaration} for which the given variable name is used to navigate to the
* "root" object. This goes up the hierarchy when looking for the {@link Declaration} if it's not
* defined in the current context.
*
* @param variableName The name of the identification variable that is used to navigate a "root" object
* @return The {@link Declaration} containing the information about the identification variable declaration
* @see #getDeclaration(String)
*/
Declaration findDeclaration(String variableName) {
return currentContext.findDeclarationImp(variableName);
}
Declaration findDeclarationImp(String variableName) {
Declaration declaration = getDeclarationResolverImp().getDeclaration(variableName);
if ((declaration == null) && (parent != null)) {
declaration = parent.findDeclarationImp(variableName);
}
return declaration;
}
/**
* Retrieves the cached {@link Expression} associated with the given variable name. The scope of
* the search is the entire query (going from the current query, if it's a subquery, up to the
* top-level query).
*
* @param variableName The variable name for which its associated {@link Expression} is requested
* @return The cached {@link Expression} associated with the given variable name or <code>null</code>
* if none was cached.
*/
Expression findQueryExpression(String variableName) {
return currentContext.findQueryExpressionImp(variableName);
}
Expression findQueryExpressionImp(String variableName) {
Expression expression = getQueryExpressionImp(variableName);
if ((expression == null) && (parent != null)) {
expression = parent.findQueryExpressionImp(variableName);
}
return expression;
}
/**
* Returns the parent context if the current context is not the root context.
*
* @return The parent context or <code>null</code> if the current context is the root
*/
JPQLQueryContext getActualParent() {
return parent;
}
/**
* Returns the root {@link Expression} for which all new {@link Expression expressions} a child.
*
* @return The root {@link Expression} of the query or subquery
*/
Expression getBaseExpression() {
// Retrieve the first declaration, which is the base declaration (For top-level query, it's
// always a range over an abstract schema name. For subqueries, it's either a range over an
// abstract schema name or a derived path expression)
return getDeclarationResolver().getFirstDeclaration().getQueryExpression();
}
/**
* Returns the {@link ClassLoader} used by EclipseLink to load the application's classes.
*
* @return The application's {@link ClassLoader}
*/
private ClassLoader getClassLoader() {
return getSession().getDatasourcePlatform().getConversionManager().getLoader();
}
/**
* Returns the {@link Constructor} for the given Java {@link Class}. The constructor to retrieve
* has the given parameter types.
*
* @param type The Java type for which its constructor should be retrieved
* @param parameterTypes The types of the constructor's parameters
* @return The {@link Constructor} or <code>null</code> if none exist or the privilege access
* was denied
*/
@SuppressWarnings("unchecked")
<T> Constructor<T> getConstructor(Class<?> type, Class<?>[] parameterTypes) {
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()) {
try {
return (Constructor<T>) AccessController.doPrivileged(
new PrivilegedGetConstructorFor(type, parameterTypes, true)
);
}
catch (PrivilegedActionException exception) {
return null;
}
}
return PrivilegedAccessHelper.getConstructorFor(type, parameterTypes, true);
}
catch (NoSuchMethodException e) {
return null;
}
}
/**
* Returns the current {@link JPQLQueryContext}, i.e. the context of the query being manipulated,
* which can either be the top-level query or a subquery.
*
* @return The active context
*/
JPQLQueryContext getCurrentContext() {
return currentContext;
}
/**
* Returns the current {@link Expression} being manipulated, which is either the top-level query
* or a subquery.
*
* @return Either the top-level query or a subquery
*/
org.eclipse.persistence.jpa.jpql.parser.Expression getCurrentQuery() {
return currentContext.currentQuery;
}
/**
* Returns the current {@link DatabaseQuery} being populated.
*
* @return The {@link DatabaseQuery} being populated, which can be the top-level query or a
* subquery depending on which query is been visited
*/
@SuppressWarnings("unchecked")
<T extends DatabaseQuery> T getDatabaseQuery() {
return (T) currentContext.query;
}
/**
* Retrieves the {@link Declaration} for which the given variable name is used to navigate to the
* "root" object. This does not go up the hierarchy when looking for the {@link Declaration}.
*
* @param variableName The name of the identification variable that is used to navigate a "root" object
* @return The {@link Declaration} containing the information about the identification variable declaration
* @see #findDeclaration(String)
*/
Declaration getDeclaration(String variableName) {
return getDeclarationResolver().getDeclaration(variableName);
}
/**
* Returns the {@link DeclarationResolver} of the current query's declaration. For a
* <b>SELECT</b> query, it contains the information defined in the <b>FROM</b> clause. For
* <b>DELETE</b> and <b>UPDATE</b> queries, it contains a single range declaration variable. If
* the current query is a subquery, then it contains the information defined in the
* <code>FROM</code> clause.
*
* @return The {@link DeclarationResolver} for the current query being visited
*/
DeclarationResolver getDeclarationResolver() {
return currentContext.getDeclarationResolverImp();
}
/**
* Returns the {@link DeclarationResolver} of the current query's declaration.
*
* @return The {@link DeclarationResolver} for the current query being visited
*/
DeclarationResolver getDeclarationResolverImp() {
if (declarationResolver == null) {
DeclarationResolver parentResolver = (parent == null) ? null : parent.getDeclarationResolverImp();
declarationResolver = new DeclarationResolver(this, parentResolver);
}
declarationResolver.populate(currentQuery);
return declarationResolver;
}
/**
* Returns the ordered list of {@link Declaration Declarations}.
*
* @return The {@link Declaration Declarations} of the current query that was parsed
*/
List<Declaration> getDeclarations() {
return getDeclarationResolver().getDeclarations();
}
/**
* Retrieves the descriptor associated with the given type.
*
* @param type The type associated with the descriptor
* @return The EclipseLink {@link ClassDescriptor descriptor} representing the managed type
*/
ClassDescriptor getDescriptor(Class<?> type) {
return getSession().getClassDescriptor(type);
}
/**
* Retrieves the descriptor associated with the given abstract schema name, which is the
* descriptor's alias.
*
* @param abstractSchemaName The managed type name associated with the managed type
* @return The EclipseLink {@link ClassDescriptor descriptor} representing the managed type
*/
ClassDescriptor getDescriptor(String abstractSchemaName) {
return getSession().getDescriptorForAlias(abstractSchemaName);
}
/**
* Returns the {@link Class} representing the possible given enum constant. If the given value
* does not represent an enum constant, then <code>null</code> is returned.
*
* @param enumTypeName The fully qualified enum type with the constant
* @return The external form for the given Enum type or <code>null</code> if none exists
*/
Class<?> getEnumType(String enumTypeName) {
// Get the position of the last dot so we can remove the constant
int lastDotIndex = enumTypeName.lastIndexOf(".");
if (lastDotIndex == -1) {
return null;
}
// Retrieve the fully qualified enum type name
String typeName = enumTypeName.substring(0, lastDotIndex);
// Attempt to load the enum type
Class<?> type = getType(typeName);
return ((type != null) && type.isEnum()) ? type : null;
}
/**
* Returns the first {@link Declaration} of the current context that was created after visiting
* the declaration clause.
*
* @return The first {@link Declaration} object
*/
Declaration getFirstDeclaration() {
return currentContext.getFirstDeclarationImp();
}
/**
* Returns the first {@link Declaration}, from this context, that was created after visiting the
* declaration clause.
*
* @return The first {@link Declaration} object
*/
Declaration getFirstDeclarationImp() {
return getDeclarationResolverImp().getFirstDeclaration();
}
/**
* Returns the {@link JPQLGrammar} that defines how the JPQL query was parsed.
*
* @return The {@link JPQLGrammar} that was used to parse the JPQL query
*/
JPQLGrammar getGrammar() {
return jpqlGrammar;
}
/**
* Returns the parsed representation of a <b>JOIN FETCH</b> that were defined in the same
* declaration than the given range identification variable name.
*
* @param variableName The name of the identification variable that should be used to define an
* abstract schema name
* @return The <b>JOIN FETCH</b> expressions used in the same declaration or an empty collection
* if none was defined
*/
Collection<Join> getJoinFetches(String variableName) {
return getDeclarationResolver().getJoinFetches(variableName);
}
/**
* Returns the parsed tree representation of the JPQL query.
*
* @return The parsed tree representation of the JPQL query
*/
JPQLExpression getJPQLExpression() {
return (parent != null) ? parent.getJPQLExpression() : jpqlExpression;
}
/**
* Returns the string representation of the JPQL query.
*
* @return The string representation of the JPQL query
*/
CharSequence getJPQLQuery() {
return (parent != null) ? parent.getJPQLQuery() : jpqlQuery;
}
/**
* Retrieves, if it can be determined, the type of the given {@link InputParameter}. The type
* will be guessed based on its location within expression.
* <p>
* Note: Both named and positional input parameter can be used.
*
* @param inputParameter The {@link InputParameter} to retrieve its type
* @return Either the closest type of the input parameter or <code>null</code> if the type could
* not be determined
*/
Class<?> getParameterType(InputParameter inputParameter) {
ParameterTypeVisitor resolver = parameterTypeVisitor();
try {
inputParameter.accept(resolver);
return resolver.getType();
}
finally {
resolver.dispose();
}
}
/**
* Returns the parent context if the current context is not the root context.
*
* @return The parent context or <code>null</code> if the current context is the root
*/
JPQLQueryContext getParent() {
return currentContext.parent;
}
/**
* Retrieves the cached {@link Expression} associated with the given variable name. The scope of
* the search is local to the current query or subquery.
*
* @param variableName The variable name for which its associated {@link Expression} is requested
* @return The cached {@link Expression} associated with the given variable name or <code>null</code>
* if none was cached.
*/
Expression getQueryExpression(String variableName) {
return currentContext.getQueryExpressionImp(variableName);
}
/**
* Retrieves the cached {@link Expression} associated with the given variable name.
*
* @param variableName The variable name for which its associated {@link Expression} is requested
* @return The cached {@link Expression} associated with the given variable name or <code>null</code>
* if none was cached.
*/
Expression getQueryExpressionImp(String variableName) {
return (expressions == null) ? null : expressions.get(variableName);
}
/**
* Returns the EclipseLink {@link AbstractSession} that this query will execute against, which
* gives access to the JPA artifacts.
*
* @return The current EclipseLink session
*/
AbstractSession getSession() {
return (parent != null) ? parent.getSession() : session;
}
/**
* Returns the Java class of the given {@link Expression}.
*
* @param expression The {@link Expression} for which its type will be calculated
* @return Either the Java class that was resolved or the <code>null</code> if it could not be resolved
*/
Class<?> getType(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
return typeResolver().resolve(expression);
}
/**
* Retrieves the external class for the given fully qualified class name.
*
* @param typeName The fully qualified class name of the class to retrieve
* @return The external form of the class to retrieve
*/
Class<?> getType(String typeName) {
return loadTypeImp(typeName);
}
private Map<String, Class<?>> getTypes() {
if (parent != null) {
return parent.getTypes();
}
if (types == null) {
types = new HashMap<String, Class<?>>();
}
return types;
}
/**
* Returns the identification variables that was used in the current query.
*
* @return The identification variables that were used throughout the current query at the
* exception of their declaration
*/
Set<String> getUsedIdentificationVariables() {
return currentContext.getUsedIdentificationVariablesImp();
}
/**
* Returns the identification variables that are registered in this context.
*
* @return The identification variables that were used throughout the current query at the
* exception of their declaration
*/
Set<String> getUsedIdentificationVariablesImp() {
if (usedIdentificationVariables == null) {
return Collections.emptySet();
}
return usedIdentificationVariables;
}
/**
* Determines whether the given identification variable is defining a join or a collection member
* declaration expressions.
*
* @param variableName The identification variable to check for what it maps
* @return <code>true</code> if the given identification variable maps a collection-valued field
* defined in a <code>JOIN</code> or <code>IN</code> expression; <code>false</code> if it's not
* defined or it's mapping an abstract schema name
*/
boolean isCollectionIdentificationVariable(String variableName) {
return getDeclarationResolver().isCollectionIdentificationVariable(variableName);
}
/**
* Determines whether the given identification variable is used, at the exception of where it was
* defined.
*
* @param variableName The identification variable to check if it was used in a clause
* @return <code>true</code> if the identification is used in a clause, at the exception of where
* it was defined; <code>false</code> otherwise
*/
boolean isIdentificationVariableUsed(String variableName) {
return currentContext.isIdentificationVariableUsedImp(variableName);
}
private boolean isIdentificationVariableUsedImp(String variableName) {
boolean result = (usedIdentificationVariables != null) && usedIdentificationVariables.contains(variableName);
if (!result && (parent != null)) {
result = parent.isIdentificationVariableUsedImp(variableName);
}
return result;
}
/**
* Determines whether the given variable name is an identification variable name used to define
* an abstract schema name.
*
* @param variableName The name of the variable to verify if it's defined in a range variable
* declaration in the current query or any parent query
* @return <code>true</code> if the variable name is mapping an abstract schema name; <code>false</code>
* if it's defined in a collection member declaration
*/
boolean isRangeIdentificationVariable(String variableName) {
return getDeclarationResolverImp().isRangeIdentificationVariable(variableName);
}
/**
* Determines if the given variable is a result variable.
*
* @param variableName The variable to check if it's a result variable
* @return <code>true</code> if the given variable is defined as a result variable;
* <code>false</code> otherwise
*/
boolean isResultVariable(String variableName) {
return getDeclarationResolverImp().isResultVariable(variableName);
}
/**
* Retrieves the "literal" from the given {@link Expression}. The literal to retrieve depends on
* the given {@link LiteralType type}. The literal is basically a string value like an
* identification variable name, an input parameter, a path expression, an abstract schema name,
* etc.
*
* @param expression The {@link Expression} to visit
* @param type The {@link LiteralType} helps to determine what to retrieve from the visited
* {@link Expression}
* @return A value from the given {@link Expression} or an empty string if the given {@link
* Expression} and the {@link LiteralType} do not match
*/
String literal(org.eclipse.persistence.jpa.jpql.parser.Expression expression, LiteralType type) {
LiteralVisitor visitor = literalVisitor();
try {
visitor.setType(type);
expression.accept(visitor);
// Make sure the identification variable is capitalized and unique since
// String.equals() is used rather than String.equalsIgnoreCase()
if (visitor.literal != ExpressionTools.EMPTY_STRING &&
(type == LiteralType.IDENTIFICATION_VARIABLE ||
type == LiteralType.RESULT_VARIABLE||
type == LiteralType.PATH_EXPRESSION_IDENTIFICATION_VARIABLE)) {
return visitor.literal.toUpperCase().intern();
}
return visitor.literal;
}
finally {
visitor.literal = ExpressionTools.EMPTY_STRING;
}
}
private LiteralVisitor literalVisitor() {
if (parent != null) {
return parent.literalVisitor();
}
if (literalVisitor == null) {
literalVisitor = new EclipseLinkLiteralVisitor();
}
return literalVisitor;
}
private Class<?> loadInnerType(String typeName) {
int index = typeName.lastIndexOf(".");
if (index == -1) {
return null;
}
StringBuilder sb = new StringBuilder();
sb.append(typeName.substring(0, index));
sb.append("$");
sb.append(typeName.substring(index + 1, typeName.length()));
typeName = sb.toString();
return loadTypeImp(typeName);
}
private Class<?> loadTypeImp(String typeName) {
Map<String, Class<?>> types = getTypes();
Class<?> type = types.get(typeName);
// The type was already cached, simply return it
if (type != null) {
return type;
}
// Attempt to load the Java type
Class<?> javaType = attemptLoadType(typeName);
// A Java type exists, return it
if (javaType != null) {
types.put(javaType.getName(), javaType);
return javaType;
}
// Now try with a possible inner enum type
return loadInnerType(typeName);
}
/**
* Creates a new instance from the given Java type.
*
* @param type The Java type for which a new instance will be created
* @param parameterType The type of the constructor's single parameter
* @param parameter The object to pass during instantiation
* @return A new instance or <code>null</code> if a problem was encountered during instantiation
*/
@SuppressWarnings("unchecked")
<T> T newInstance(Class<?> type, Class<?> parameterType, Object parameter) {
return (T) newInstance(type, new Class[] { parameterType }, new Object[] { parameter });
}
/**
* Creates a new instance from the given Java type.
*
* @param type The Java type for which a new instance will be created
* @param parameterTypes The types of the constructor's parameters
* @param parameters The objects to pass during instantiation
* @return A new instance of the given type or <code>null</code> if a problem was encountered
* during instantiation
*/
<T> T newInstance(Class<?> type, Class<?>[] parameterTypes, Object[] parameters) {
Constructor<T> constructor = getConstructor(type, parameterTypes);
if (constructor != null) {
return newInstance(constructor, parameters);
}
return null;
}
/**
* Creates a new instance by using the given constructor.
*
* @param constructor The constructor used to create the new instance
* @param parameters The objects to pass during instantiation
* @return A new instance or <code>null</code> if a problem was encountered during instantiation
*/
@SuppressWarnings("unchecked")
<T> T newInstance(Constructor<T> constructor, Object[] parameters) {
try {
if (PrivilegedAccessHelper.shouldUsePrivilegedAccess()) {
try {
return (T) AccessController.doPrivileged(
new PrivilegedInvokeConstructor(constructor, parameters)
);
}
catch (PrivilegedActionException exception) {
return null;
}
}
return (T) PrivilegedAccessHelper.invokeConstructor(constructor, parameters);
}
catch (InstantiationException e) {
return null;
}
catch (InvocationTargetException e) {
return null;
}
catch (IllegalAccessException e) {
return null;
}
}
/**
* Changes the state of this context to use the given subquery. Once the subquery is created and
* populated, {@link #disposeSubqueryContext()} has to be called.
*
* @param currentQuery The parsed tree representation of the subquery that will become the
* current {@link DatabaseQuery}
* @param query The {@link ReportQuery} for the subquery
* @see #disposeSubqueryContext()
*/
void newSubQueryContext(org.eclipse.persistence.jpa.jpql.parser.Expression currentQuery,
ReportQuery query) {
currentContext = new JPQLQueryContext(currentContext, currentQuery, query);
}
private ParameterTypeVisitor parameterTypeVisitor() {
if (parent != null) {
return parent.parameterTypeVisitor();
}
if (parameterTypeVisitor == null) {
parameterTypeVisitor = new ParameterTypeVisitor(this);
}
return parameterTypeVisitor;
}
private JPQLExpression parse(String jpqlQuery) {
return new JPQLExpression(jpqlQuery, jpqlGrammar);
}
/**
* Resolves the given {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression} and
* returns the corresponding descriptor. Usually this method is used when retrieving the
* descriptor for an identification variable or a path expression. In the case of a range
* variable declaration, the descriptor of the entity is returned. In the case of a path
* expression, the mapping reference descriptor will be returned.
*
* @param expression The {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression}
*/
ClassDescriptor resolveDescriptor(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
return typeResolver().resolveDescriptor(expression);
}
/**
* Resolves the given {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression} and
* returns the {@link DatabaseMapping}.
*
* @param expression The {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression} to
* resolve by traversing its path expression
* @return The {@link DatabaseMapping} that is representing the last path or <code>null</code> if
* the path expression could not be resolved
*/
DatabaseMapping resolveMapping(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
return typeResolver().resolveMapping(expression);
}
/**
* Resolves the given {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression} and
* either returns the {@link DatabaseMapping} or the {@link QueryKey} object.
*
* @param expression The {@link org.eclipse.persistence.jpa.jpql.parser.Expression Expression} to
* resolve by traversing its path expression
* @return Either the {@link DatabaseMapping} or the {@link QueryKey} that is representing the
* last path or <code>null</code> if the path expression could not be resolved
*/
Object resolveMappingObject(org.eclipse.persistence.jpa.jpql.parser.Expression expression) {
return typeResolver().resolveMappingObject(expression);
}
/**
* Sets the query to populate.
*
* @param query The {@link DatabaseQuery} that was created before populating it
*/
void setDatabasQuery(DatabaseQuery query) {
this.query = query;
}
TypeResolver typeResolver() {
if (parent != null) {
return parent.typeResolver();
}
if (typeResolver == null) {
typeResolver = new TypeResolver(this);
}
return typeResolver;
}
}