/*******************************************************************************
* Copyright (c) 2006, 2015 Oracle and/or its affiliates. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public 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.jpa.jpql.tools.resolver;
import java.sql.Date;
import java.sql.Time;
import java.sql.Timestamp;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.eclipse.persistence.jpa.jpql.Assert;
import org.eclipse.persistence.jpa.jpql.ExpressionTools;
import org.eclipse.persistence.jpa.jpql.LiteralType;
import org.eclipse.persistence.jpa.jpql.parser.AbsExpression;
import org.eclipse.persistence.jpa.jpql.parser.AbstractExpressionVisitor;
import org.eclipse.persistence.jpa.jpql.parser.AbstractPathExpression;
import org.eclipse.persistence.jpa.jpql.parser.AbstractSchemaName;
import org.eclipse.persistence.jpa.jpql.parser.AdditionExpression;
import org.eclipse.persistence.jpa.jpql.parser.AllOrAnyExpression;
import org.eclipse.persistence.jpa.jpql.parser.AndExpression;
import org.eclipse.persistence.jpa.jpql.parser.ArithmeticExpression;
import org.eclipse.persistence.jpa.jpql.parser.ArithmeticFactor;
import org.eclipse.persistence.jpa.jpql.parser.AvgFunction;
import org.eclipse.persistence.jpa.jpql.parser.BadExpression;
import org.eclipse.persistence.jpa.jpql.parser.BetweenExpression;
import org.eclipse.persistence.jpa.jpql.parser.CaseExpression;
import org.eclipse.persistence.jpa.jpql.parser.CoalesceExpression;
import org.eclipse.persistence.jpa.jpql.parser.CollectionExpression;
import org.eclipse.persistence.jpa.jpql.parser.CollectionMemberDeclaration;
import org.eclipse.persistence.jpa.jpql.parser.CollectionMemberExpression;
import org.eclipse.persistence.jpa.jpql.parser.CollectionValuedPathExpression;
import org.eclipse.persistence.jpa.jpql.parser.ComparisonExpression;
import org.eclipse.persistence.jpa.jpql.parser.ConcatExpression;
import org.eclipse.persistence.jpa.jpql.parser.ConstructorExpression;
import org.eclipse.persistence.jpa.jpql.parser.CountFunction;
import org.eclipse.persistence.jpa.jpql.parser.DateTime;
import org.eclipse.persistence.jpa.jpql.parser.DeleteClause;
import org.eclipse.persistence.jpa.jpql.parser.DeleteStatement;
import org.eclipse.persistence.jpa.jpql.parser.DivisionExpression;
import org.eclipse.persistence.jpa.jpql.parser.EmptyCollectionComparisonExpression;
import org.eclipse.persistence.jpa.jpql.parser.EntityTypeLiteral;
import org.eclipse.persistence.jpa.jpql.parser.EntryExpression;
import org.eclipse.persistence.jpa.jpql.parser.ExistsExpression;
import org.eclipse.persistence.jpa.jpql.parser.Expression;
import org.eclipse.persistence.jpa.jpql.parser.ExpressionVisitor;
import org.eclipse.persistence.jpa.jpql.parser.FromClause;
import org.eclipse.persistence.jpa.jpql.parser.FunctionExpression;
import org.eclipse.persistence.jpa.jpql.parser.GroupByClause;
import org.eclipse.persistence.jpa.jpql.parser.HavingClause;
import org.eclipse.persistence.jpa.jpql.parser.IdentificationVariable;
import org.eclipse.persistence.jpa.jpql.parser.IdentificationVariableDeclaration;
import org.eclipse.persistence.jpa.jpql.parser.InExpression;
import org.eclipse.persistence.jpa.jpql.parser.IndexExpression;
import org.eclipse.persistence.jpa.jpql.parser.InputParameter;
import org.eclipse.persistence.jpa.jpql.parser.JPQLExpression;
import org.eclipse.persistence.jpa.jpql.parser.Join;
import org.eclipse.persistence.jpa.jpql.parser.KeyExpression;
import org.eclipse.persistence.jpa.jpql.parser.KeywordExpression;
import org.eclipse.persistence.jpa.jpql.parser.LengthExpression;
import org.eclipse.persistence.jpa.jpql.parser.LikeExpression;
import org.eclipse.persistence.jpa.jpql.parser.LocateExpression;
import org.eclipse.persistence.jpa.jpql.parser.LowerExpression;
import org.eclipse.persistence.jpa.jpql.parser.MaxFunction;
import org.eclipse.persistence.jpa.jpql.parser.MinFunction;
import org.eclipse.persistence.jpa.jpql.parser.ModExpression;
import org.eclipse.persistence.jpa.jpql.parser.MultiplicationExpression;
import org.eclipse.persistence.jpa.jpql.parser.NotExpression;
import org.eclipse.persistence.jpa.jpql.parser.NullComparisonExpression;
import org.eclipse.persistence.jpa.jpql.parser.NullExpression;
import org.eclipse.persistence.jpa.jpql.parser.NullIfExpression;
import org.eclipse.persistence.jpa.jpql.parser.NumericLiteral;
import org.eclipse.persistence.jpa.jpql.parser.ObjectExpression;
import org.eclipse.persistence.jpa.jpql.parser.OnClause;
import org.eclipse.persistence.jpa.jpql.parser.OrExpression;
import org.eclipse.persistence.jpa.jpql.parser.OrderByClause;
import org.eclipse.persistence.jpa.jpql.parser.OrderByItem;
import org.eclipse.persistence.jpa.jpql.parser.RangeVariableDeclaration;
import org.eclipse.persistence.jpa.jpql.parser.ResultVariable;
import org.eclipse.persistence.jpa.jpql.parser.SelectClause;
import org.eclipse.persistence.jpa.jpql.parser.SelectStatement;
import org.eclipse.persistence.jpa.jpql.parser.SimpleFromClause;
import org.eclipse.persistence.jpa.jpql.parser.SimpleSelectClause;
import org.eclipse.persistence.jpa.jpql.parser.SimpleSelectStatement;
import org.eclipse.persistence.jpa.jpql.parser.SizeExpression;
import org.eclipse.persistence.jpa.jpql.parser.SqrtExpression;
import org.eclipse.persistence.jpa.jpql.parser.StateFieldPathExpression;
import org.eclipse.persistence.jpa.jpql.parser.StringLiteral;
import org.eclipse.persistence.jpa.jpql.parser.SubExpression;
import org.eclipse.persistence.jpa.jpql.parser.SubstringExpression;
import org.eclipse.persistence.jpa.jpql.parser.SubtractionExpression;
import org.eclipse.persistence.jpa.jpql.parser.SumFunction;
import org.eclipse.persistence.jpa.jpql.parser.TreatExpression;
import org.eclipse.persistence.jpa.jpql.parser.TrimExpression;
import org.eclipse.persistence.jpa.jpql.parser.TypeExpression;
import org.eclipse.persistence.jpa.jpql.parser.UnknownExpression;
import org.eclipse.persistence.jpa.jpql.parser.UpdateClause;
import org.eclipse.persistence.jpa.jpql.parser.UpdateItem;
import org.eclipse.persistence.jpa.jpql.parser.UpdateStatement;
import org.eclipse.persistence.jpa.jpql.parser.UpperExpression;
import org.eclipse.persistence.jpa.jpql.parser.ValueExpression;
import org.eclipse.persistence.jpa.jpql.parser.WhenClause;
import org.eclipse.persistence.jpa.jpql.parser.WhereClause;
import org.eclipse.persistence.jpa.jpql.tools.JPQLQueryContext;
import org.eclipse.persistence.jpa.jpql.tools.spi.IType;
/**
* This visitor creates a {@link Resolver} that gives information about the visited {@link Expression}.
* The actual {@link Resolver} will calculate the proper {@link IType} as well.
* <p>
* The type of an {@link Expression} follows the following rules:
* <ul>
* <li>The type of the query result specified by the <b>SELECT</b> clause of a query is an entity
* abstract schema type, a state field type, the result of a scalar expression, the result of an
* aggregate function, the result of a construction operation, or some sequence of these.</li>
*
* <li>The result type of the <b>SELECT</b> clause is defined by the result types of the select
* expressions contained in it. When multiple select expressions are used in the <b>SELECT</b>
* clause, the elements in this result correspond in order to the order of their specification in
* the <b>SELECT</b> clause and in type to the result types of each of the select expressions.</li>
*
* <li>The result type of an <code>identification_variable</code> is the type of the entity object
* or embeddable object to which the identification variable corresponds. The type of an
* <code>identification_variable</code> that refers to an entity abstract schema type is the type of
* the entity to which that identification variable corresponds or a subtype as determined by the
* object/relational mapping.</li>
*
* <li>The result type of a <code>single_valued_path_expression</code> that is a
* <code>state_field_path_expression</code> is the same type as the corresponding state field of the
* entity or embeddable class. If the state field of the entity is a primitive type, the result type
* is the corresponding object type.</li>
*
* <li>The result type of a <code>single_valued_path_expression</code> that is a
* <code>single_valued_object_path_expression</code> is the type of the entity object or embeddable
* object to which the path expression corresponds. A
* <code>single_valued_object_path_expression</code> that results in an entity object will result in
* an entity of the type of the relationship field or the subtype of the relationship field of the
* entity object as determined by the object/relational mapping.</li>
*
* <li>The result type of a <code>single_valued_path_expression</code> that is an
* identification_variable to which the <code>KEY</code> or <code>VALUE</code> function has been
* applied is determined by the type of the map key or value respectively, as defined by the above
* rules.</li>
*
* <li>The result type of a <code>single_valued_path_expression</code> that is an
* identification_variable to which the <code>ENTRY</code> function has been applied is
* {@link java.util.Map.Entry Map.Entry}, where the key and value types of the map entry are
* determined by the above rules as applied to the map key and map value respectively.</li>
*
* <li>The result type of a <code>scalar_expression</code> is the type of the scalar value to which
* the expression evaluates.</li>
*
* <li>The result type of an <code>entity_type_expression</code> scalar expression is the Java class
* to which the resulting abstract schema type corresponds.</li>
*
* <li>The result type of a <code>constructor_expression</code> is the type of the class for which
* the constructor is defined. The types of the arguments to the constructor are defined by the
* above rules.</li>
* </ul>
* <p>
* 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.
*
* @version 2.5.1
* @since 2.3
* @author Pascal Filion
*/
@SuppressWarnings("nls")
public abstract class ResolverBuilder implements ExpressionVisitor {
/**
* This visitor is responsible to retrieve the {@link CollectionExpression} if it is visited.
*/
private CollectionExpressionVisitor collectionExpressionVisitor;
/**
* The context used to query information about the JPQL query.
*/
private final JPQLQueryContext queryContext;
/**
* The {@link Resolver} for the {@link Expression} that was visited.
*/
protected Resolver resolver;
/**
* Creates a new <code>ResolverBuilder</code>.
*
* @param queryContext The context used to query information about the JPQL query
* @exception NullPointerException The {@link JPQLQueryContext} cannot be <code>null</code>
*/
public ResolverBuilder(JPQLQueryContext queryContext) {
super();
Assert.isNotNull(queryContext, "The JPQLQueryContext cannot be null");
this.queryContext = queryContext;
}
/**
* Creates a new {link Resolver} that simply wraps the already determined type by using its
* fully qualified class name.
*
* @param typeName The fully qualified class name of the Java type to wrap with a {@link Resolver}
* @return A new {@link Resolver}
*/
protected Resolver buildClassNameResolver(String typeName) {
return new ClassNameResolver(getDeclarationResolver(), typeName);
}
/**
* Creates a new {link Resolver} that simply wraps the already determined type.
*
* @param type The Java type to wrap with a {@link Resolver}
* @return A new {@link Resolver}
*/
protected Resolver buildClassResolver(Class<?> type) {
return new ClassResolver(getDeclarationResolver(), type);
}
/**
* Creates a visitor that collects the {@link CollectionExpression} if it's been visited.
*
* @return A new {@link CollectionExpressionVisitor}
*/
protected CollectionExpressionVisitor buildCollectionExpressionVisitor() {
return new CollectionExpressionVisitor();
}
/**
* Creates a new {@link Resolver} for the given collection-valued path expression.
*
* @param variableName The last segment of the collection-valued path expression
* @return A new {@link Resolver} that can get the information for a collection-valued path
*/
protected Resolver buildCollectionValuedFieldResolver(String variableName) {
Resolver resolver = this.resolver.getChild(variableName);
if (resolver == null) {
resolver = new CollectionValuedFieldResolver(this.resolver, variableName);
}
return resolver;
}
/**
* Creates a new {@link Resolver} that will resolve the given enum literal.
*
* @param expression The {@link Expression} that represents the enum literal
* @param type The {@link IType} representing the {@link Enum} type
* @param enumLiteral The fully qualified enum constant
* @return The {@link Resolver} for an enum literal
*/
protected Resolver buildEnumResolver(AbstractPathExpression expression,
IType type,
String enumLiteral) {
DeclarationResolver parent = getDeclarationResolver(expression);
return new EnumLiteralResolver(parent, type, enumLiteral);
}
/**
* Creates a new {@link Resolver} that is used when nothing can be resolved.
*
* @return A "<code>null</code>" version of a {@link Resolver}
*/
protected Resolver buildNullResolver() {
return new NullResolver(getDeclarationResolver());
}
/**
* Creates a new {@link Resolver} for the given state field path expression.
*
* @param variableName The last segment of the state field path expression
* @return A new {@link Resolver} that can get the information for a state field path
*/
protected Resolver buildStateFieldResolver(String variableName) {
Resolver resolver = this.resolver.getChild(variableName);
if (resolver == null) {
resolver = new StateFieldResolver(this.resolver, variableName);
}
return resolver;
}
/**
* Disposes the internal data of this resolver.
*/
public void dispose() {
resolver = null;
}
/**
* Casts the given {@link Expression} to a {@link CollectionExpression} if it is actually an
* object of that type.
*
* @param expression The {@link Expression} to cast
* @return The given {@link Expression} if it is a {@link CollectionExpression} or <code>null</code>
* if it is any other object
*/
protected CollectionExpression getCollectionExpression(Expression expression) {
CollectionExpressionVisitor visitor = getCollectionExpressionVisitor();
try {
expression.accept(visitor);
return visitor.expression;
}
finally {
visitor.expression = null;
}
}
/**
* Returns the visitor that collects the {@link CollectionExpression} if it's been visited.
*
* @return The {@link CollectionExpressionVisitor}
* @see #buildCollectionExpressionVisitor()
*/
protected CollectionExpressionVisitor getCollectionExpressionVisitor() {
if (collectionExpressionVisitor == null) {
collectionExpressionVisitor = buildCollectionExpressionVisitor();
}
return collectionExpressionVisitor;
}
/**
* 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
*/
protected DeclarationResolver getDeclarationResolver() {
return queryContext.getDeclarationResolver();
}
/**
* 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 variable declaration. If
* the current query is a subquery, then it contains the information defined in the subquery
* <code>FROM</code> clause.
*
* @param expression The {@link Expression} that will be used to retrieve its query expression,
* i.e. either {@link JPQLExpression} or {@link SimpleSelectStatement}
* @return The {@link DeclarationResolver} for the current query being visited
*/
protected DeclarationResolver getDeclarationResolver(Expression expression) {
return queryContext.getDeclarationResolver(expression);
}
/**
* Returns the {@link JPQLQueryContext} that contains information related to the JPQL query.
*
* @return The {@link JPQLQueryContext}, which is never <code>null</code>
*/
protected JPQLQueryContext getQueryContext() {
return queryContext;
}
/**
* Returns the current {@link Resolver} used to resolve an {@link Expression}.
*
* @return The current {@link Resolver}, which should never be <code>null</code>
*/
public Resolver getResolver() {
return resolver;
}
/**
* {@inheritDoc}
*/
public void visit(AbsExpression expression) {
// Visit the child expression in order to create the resolver
expression.getExpression().accept(this);
// Wrap the Resolver used to determine the type of the state field
// path expression so we can return the actual type
resolver = new AbsFunctionResolver(resolver);
}
/**
* {@inheritDoc}
*/
public void visit(AbstractSchemaName expression) {
String abstractSchemaName = expression.getText();
if (ExpressionTools.stringIsNotEmpty(abstractSchemaName)) {
DeclarationResolver parent = getDeclarationResolver(expression);
if (queryContext.isSubquery()) {
resolver = new SubqueryEntityResolver(parent, queryContext.getCurrentContext(), expression);
}
else {
resolver = new EntityResolver(parent, abstractSchemaName);
}
}
else {
resolver = buildNullResolver();
}
}
/**
* {@inheritDoc}
*/
public void visit(AdditionExpression expression) {
visitArithmeticExpression(expression);
}
/**
* {@inheritDoc}
*/
public void visit(AllOrAnyExpression expression) {
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(AndExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(ArithmeticFactor expression) {
// First traverse the expression
expression.getExpression().accept(this);
// Make sure the type is a numeric type
DeclarationResolver parent = getDeclarationResolver(expression);
resolver = new NumericResolver(parent, resolver);
}
/**
* {@inheritDoc}
*/
public void visit(AvgFunction expression) {
resolver = buildClassResolver(Double.class);
}
/**
* {@inheritDoc}
*/
public void visit(BadExpression expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(BetweenExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(CaseExpression expression) {
visitCollectionEquivalentExpression(
expression.getWhenClauses(),
expression.getElseExpression()
);
}
/**
* {@inheritDoc}
*/
public void visit(CoalesceExpression expression) {
visitCollectionEquivalentExpression(expression.getExpression(), null);
}
/**
* {@inheritDoc}
*/
public void visit(CollectionExpression expression) {
expression.acceptChildren(this);
}
/**
* {@inheritDoc}
*/
public void visit(CollectionMemberDeclaration expression) {
expression.getCollectionValuedPathExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(CollectionMemberExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(CollectionValuedPathExpression expression) {
// If the path ends with '.', then the path is incomplete
// so we can't resolve the type
if (!expression.endsWithDot()) {
// Check first to see if it's an enum type
String path = expression.toActualText();
IType type = queryContext.getTypeRepository().getEnumType(path);
if (type != null) {
resolver = buildEnumResolver(expression, type, path);
}
else {
expression.getIdentificationVariable().accept(this);
for (int index = expression.hasVirtualIdentificationVariable() ? 0 : 1, count = expression.pathSize(); index < count; index++) {
path = expression.getPath(index);
if (index + 1 < count) {
resolver = buildStateFieldResolver(path);
}
else {
resolver = buildCollectionValuedFieldResolver(path);
}
}
}
}
else {
resolver = buildNullResolver();
}
}
/**
* {@inheritDoc}
*/
public void visit(ComparisonExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(ConcatExpression expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(ConstructorExpression expression) {
String className = expression.getClassName();
if (ExpressionTools.stringIsNotEmpty(className)) {
resolver = buildClassNameResolver(className);
}
else {
resolver = buildNullResolver();
}
}
/**
* {@inheritDoc}
*/
public void visit(CountFunction expression) {
resolver = buildClassResolver(Long.class);
}
/**
* {@inheritDoc}
*/
public void visit(DateTime expression) {
if (expression.isCurrentDate()) {
resolver = buildClassResolver(Date.class);
}
else if (expression.isCurrentTime()) {
resolver = buildClassResolver(Time.class);
}
else if (expression.isCurrentTimestamp()) {
resolver = buildClassResolver(Timestamp.class);
}
else {
String text = expression.getText();
if (text.startsWith("{d")) {
resolver = buildClassResolver(Date.class);
}
else if (text.startsWith("{ts")) {
resolver = buildClassResolver(Timestamp.class);
}
else if (text.startsWith("{t")) {
resolver = buildClassResolver(Time.class);
}
else {
resolver = buildNullResolver();
}
}
}
/**
* {@inheritDoc}
*/
public void visit(DeleteClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(DeleteStatement expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(DivisionExpression expression) {
visitArithmeticExpression(expression);
}
/**
* {@inheritDoc}
*/
public void visit(EmptyCollectionComparisonExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(EntityTypeLiteral expression) {
String entityTypeName = expression.getEntityTypeName();
if (ExpressionTools.stringIsNotEmpty(entityTypeName)) {
DeclarationResolver parent = getDeclarationResolver(expression);
resolver = new EntityResolver(parent, entityTypeName);
}
else {
resolver = buildNullResolver();
}
}
/**
* {@inheritDoc}
*/
public void visit(EntryExpression expression) {
resolver = buildClassResolver(Map.Entry.class);
}
/**
* {@inheritDoc}
*/
public void visit(ExistsExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(FromClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(FunctionExpression expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(GroupByClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(HavingClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(IdentificationVariable expression) {
DeclarationResolver parent = getDeclarationResolver(expression);
resolver = parent.getResolver(expression.getVariableName());
}
/**
* {@inheritDoc}
*/
public void visit(IdentificationVariableDeclaration expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(IndexExpression expression) {
resolver = buildClassResolver(Integer.class);
}
/**
* {@inheritDoc}
*/
public void visit(InExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(InputParameter expression) {
resolver = buildClassNameResolver(IType.UNRESOLVABLE_TYPE);
}
/**
* {@inheritDoc}
*/
public void visit(Join expression) {
expression.getJoinAssociationPath().accept(this);
resolver.setNullAllowed(expression.isLeftJoin());
}
/**
* {@inheritDoc}
*/
public void visit(JPQLExpression expression) {
expression.getQueryStatement().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(KeyExpression expression) {
// Visit the identification variable in order to create the resolver
expression.getExpression().accept(this);
// Wrap the Resolver used to determine the type of the identification
// variable so we can return the actual type
resolver = new KeyResolver(resolver);
}
/**
* {@inheritDoc}
*/
public void visit(KeywordExpression expression) {
String text = expression.getText();
if (text == KeywordExpression.FALSE ||
text == KeywordExpression.TRUE) {
resolver = buildClassResolver(Boolean.class);
}
else {
resolver = buildClassResolver(Object.class);
}
}
/**
* {@inheritDoc}
*/
public void visit(LengthExpression expression) {
resolver = buildClassResolver(Integer.class);
}
/**
* {@inheritDoc}
*/
public void visit(LikeExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(LocateExpression expression) {
resolver = buildClassResolver(Integer.class);
}
/**
* {@inheritDoc}
*/
public void visit(LowerExpression expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(MaxFunction expression) {
// Visit the state field path expression in order to create the resolver
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(MinFunction expression) {
// Visit the state field path expression in order to create the resolver
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(ModExpression expression) {
resolver = buildClassResolver(Integer.class);
}
/**
* {@inheritDoc}
*/
public void visit(MultiplicationExpression expression) {
visitArithmeticExpression(expression);
}
/**
* {@inheritDoc}
*/
public void visit(NotExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(NullComparisonExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(NullExpression expression) {
resolver = buildClassNameResolver(IType.UNRESOLVABLE_TYPE);
}
/**
* {@inheritDoc}
*/
public void visit(NullIfExpression expression) {
expression.getFirstExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(NumericLiteral expression) {
try {
String text = expression.getText();
// Long value
// Integer value
if (ExpressionTools.LONG_REGEXP .matcher(text).matches() ||
ExpressionTools.INTEGER_REGEXP.matcher(text).matches()) {
Long value = Long.parseLong(text);
if (value <= Integer.MAX_VALUE) {
resolver = buildClassResolver(Integer.class);
}
else {
resolver = buildClassResolver(Long.class);
}
}
// Float
else if (ExpressionTools.FLOAT_REGEXP.matcher(text).matches()) {
resolver = buildClassResolver(Float.class);
}
// Decimal
else if (ExpressionTools.DOUBLE_REGEXP.matcher(text).matches()) {
resolver = buildClassResolver(Double.class);
}
}
catch (Exception e) {
resolver = buildClassResolver(Object.class);
}
}
/**
* {@inheritDoc}
*/
public void visit(ObjectExpression expression) {
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(OnClause expression) {
expression.getConditionalExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(OrderByClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(OrderByItem expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(OrExpression expression) {
resolver = buildClassResolver(Boolean.class);
}
/**
* {@inheritDoc}
*/
public void visit(RangeVariableDeclaration expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(ResultVariable expression) {
expression.getSelectExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(SelectClause expression) {
Expression selectExpression = expression.getSelectExpression();
// visit(CollectionExpression) iterates through the children but for a
// SELECT clause, a CollectionExpression means the result type is Object[]
CollectionExpression collectionExpression = getCollectionExpression(selectExpression);
if (collectionExpression != null) {
resolver = buildClassResolver(Object[].class);
}
else {
selectExpression.accept(this);
}
}
/**
* {@inheritDoc}
*/
public void visit(SelectStatement expression) {
expression.getSelectClause().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(SimpleFromClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(SimpleSelectClause expression) {
expression.getSelectExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(SimpleSelectStatement expression) {
queryContext.newSubqueryContext(expression);
try {
expression.getSelectClause().accept(this);
}
finally {
queryContext.disposeSubqueryContext();
}
}
/**
* {@inheritDoc}
*/
public void visit(SizeExpression expression) {
resolver = buildClassResolver(Integer.class);
}
/**
* {@inheritDoc}
*/
public void visit(SqrtExpression expression) {
resolver = buildClassResolver(Double.class);
}
/**
* {@inheritDoc}
*/
public void visit(StateFieldPathExpression expression) {
// If the path ends with '.', then the path is incomplete
// so we can't resolve the type
if (!expression.endsWithDot()) {
// Check first to see if it's an enum type
String path = expression.toActualText();
IType type = queryContext.getTypeRepository().getEnumType(path);
if (type != null) {
resolver = buildEnumResolver(expression, type, path);
}
else {
expression.getIdentificationVariable().accept(this);
for (int index = expression.hasVirtualIdentificationVariable() ? 0 : 1, count = expression.pathSize(); index < count; index++) {
path = expression.getPath(index);
resolver = buildStateFieldResolver(expression.getPath(index));
}
}
}
else {
resolver = buildNullResolver();
}
}
/**
* {@inheritDoc}
*/
public void visit(StringLiteral expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(SubExpression expression) {
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(SubstringExpression expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(SubtractionExpression expression) {
visitArithmeticExpression(expression);
}
/**
* {@inheritDoc}
*/
public void visit(SumFunction expression) {
// Visit the state field path expression in order to create the resolver
expression.getExpression().accept(this);
// Wrap the Resolver used to determine the type of the state field
// path expression so we can return the actual type
resolver = new SumFunctionResolver(resolver);
}
/**
* {@inheritDoc}
*/
public void visit(TreatExpression expression) {
// Visit the identification variable in order to create the resolver
expression.getCollectionValuedPathExpression().accept(this);
// Retrieve the entity type name
String entityTypeName = getQueryContext().literal(
expression.getEntityType(),
LiteralType.ENTITY_TYPE
);
// Wrap the Resolver for down casting
resolver = new TreatResolver(resolver, entityTypeName);
}
/**
* {@inheritDoc}
*/
public void visit(TrimExpression expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(TypeExpression expression) {
expression.getExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(UnknownExpression expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(UpdateClause expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(UpdateItem expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(UpdateStatement expression) {
resolver = buildClassResolver(Object.class);
}
/**
* {@inheritDoc}
*/
public void visit(UpperExpression expression) {
resolver = buildClassResolver(String.class);
}
/**
* {@inheritDoc}
*/
public void visit(ValueExpression expression) {
// Visit the identification variable in order to create the resolver
expression.getExpression().accept(this);
// Wrap the Resolver used to determine the type of the identification
// variable so we can return the actual type
resolver = new ValueResolver(resolver);
}
/**
* {@inheritDoc}
*/
public void visit(WhenClause expression) {
expression.getThenExpression().accept(this);
}
/**
* {@inheritDoc}
*/
public void visit(WhereClause expression) {
expression.getConditionalExpression().accept(this);
}
/**
* Visits the given {@link ArithmeticExpression} and create the appropriate {@link Resolver}.
*
* @param expression The {@link ArithmeticExpression} to visit
*/
protected void visitArithmeticExpression(ArithmeticExpression expression) {
List<Resolver> resolvers = new ArrayList<Resolver>(2);
// Visit the first expression
expression.getLeftExpression().accept(this);
resolvers.add(resolver);
// Visit the second expression
expression.getRightExpression().accept(this);
resolvers.add(resolver);
// This will resolve the correct numeric type
DeclarationResolver parent = getDeclarationResolver(expression);
resolver = new NumericResolver(parent, resolvers);
}
/**
* Visits the given {@link Expression} and creates a {@link Resolver} that will check the type
* for each of its children. If the type is the same, then it's the {@link Expression}'s type;
* otherwise the type will be {@link Object}.
*
* @param expression The {@link Expression} to calculate the type of its children
* @param extraExpression This {@link Expression} will be resolved, if it's not <code>null</code>
* and its type will be added to the collection of types
*/
protected void visitCollectionEquivalentExpression(Expression expression,
Expression extraExpression) {
List<Resolver> resolvers = new ArrayList<Resolver>();
CollectionExpression collectionExpression = getCollectionExpression(expression);
// Gather the resolver for all children
if (collectionExpression != null) {
for (Expression child : collectionExpression.children()) {
child.accept(this);
resolvers.add(resolver);
}
}
// Otherwise visit the actual expression
else {
expression.accept(this);
resolvers.add(resolver);
}
// Add the resolver for the other expression
if (extraExpression != null) {
extraExpression.accept(this);
resolvers.add(resolver);
}
DeclarationResolver parent = getDeclarationResolver(expression);
resolver = new CollectionEquivalentResolver(parent, resolvers);
}
/**
* This visitor is used to check if the expression visited is a {@link CollectionExpression}.
*/
protected static final class CollectionExpressionVisitor extends AbstractExpressionVisitor {
/**
* The {@link CollectionExpression} that was visited, otherwise <code>null</code>.
*/
protected CollectionExpression expression;
/**
* Creates a new <code>CollectionExpressionVisitor</code>.
*/
public CollectionExpressionVisitor() {
super();
}
/**
* {@inheritDoc}
*/
@Override
public void visit(CollectionExpression expression) {
this.expression = expression;
}
}
}