/*******************************************************************************
* Copyright (c) 2011, 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.model.query;
import java.io.IOException;
import java.util.List;
import java.util.ListIterator;
import org.eclipse.persistence.jpa.jpql.parser.CollectionMemberDeclaration;
import org.eclipse.persistence.jpa.jpql.tools.spi.IManagedType;
import org.eclipse.persistence.jpa.jpql.tools.utility.iterable.SingleElementListIterable;
import org.eclipse.persistence.jpa.jpql.utility.iterable.ListIterable;
import static org.eclipse.persistence.jpa.jpql.parser.AbstractExpression.*;
import static org.eclipse.persistence.jpa.jpql.parser.Expression.*;
/**
* An identification variable declared by a <code>collection_member_declaration</code> ranges over
* values of a collection obtained by navigation using a path expression. Such a path expression
* represents a navigation involving the association-fields of an entity abstract schema type.
* Because a path expression can be based on another path expression, the navigation can use the
* association-fields of related entities. An identification variable of a collection member
* declaration is declared using a special operator, the reserved identifier <code><b>IN</b></code>.
* The argument to the <code><b>IN</b></code> operator is a collection-valued path expression. The
* path expression evaluates to a collection type specified as a result of navigation to a
* collection-valued association-field of an entity abstract schema type. The syntax for declaring a
* collection member identification variable is as follows:
*
* <div><b>BNF:</b> <code>collection_member_declaration ::= IN(collection_valued_path_expression) [AS] identification_variable</code><p></div>
* or
* <div><b>BNF:</b> <code>derived_collection_member_declaration ::= IN superquery_identification_variable.{single_valued_object_field.}*collection_valued_field</code><p></div>
*
* @see FromClauseStateObject
* @see CollectionMemberDeclaration
*
* @version 2.5
* @since 2.4
* @author Pascal Filion
*/
@SuppressWarnings({"nls", "unused"}) // unused used for the import statement: see bug 330740
public class CollectionMemberDeclarationStateObject extends AbstractStateObject
implements VariableDeclarationStateObject {
/**
* Flag used to determine if the <code><b>AS</b></code> identifier is used or not.
*/
private boolean as;
/**
* The model object representing the collection-valued association-field of an entity abstract
* schema type.
*/
private CollectionValuedPathExpressionStateObject collectionValuedPath;
/**
* Determines whether this collection member declaration is used as a deriving collection-valued
* path expression.
*/
private boolean derived;
/**
* The model object representing an identification variable evaluating to a collection-valued
* association-field of an entity abstract schema type.
*/
private IdentificationVariableStateObject identificationVariable;
/**
* Notifies the visibility of the <code><b>AS</b></code> identifier has changed.
*/
public static final String AS_PROPERTY = "as";
/**
* Creates a new <code>CollectionMemberDeclarationStateObject</code>.
*
* @param parent The parent of this state object, which cannot be <code>null</code>
* @exception NullPointerException The given parent cannot be <code>null</code>
*/
public CollectionMemberDeclarationStateObject(AbstractFromClauseStateObject parent) {
super(parent);
}
/**
* Creates a new <code>CollectionMemberDeclarationStateObject</code>.
*
* @param parent The parent of this state object, which cannot be <code>null</code>
* @param paths The segments that represent the collection-valued path
* @param as Determine whether the <code><b>AS</b></code> identifier is used or not
* @param identificationVariable The identification variable declaring the collection-valued path
* @exception NullPointerException The given parent cannot be <code>null</code>
*/
public CollectionMemberDeclarationStateObject(AbstractFromClauseStateObject parent,
ListIterator<String> paths,
boolean as,
String identificationVariable) {
super(parent);
this.as = as;
getCollectionValuedPath().setPaths(paths);
setIdentificationVariable(identificationVariable);
}
/**
* Creates a new <code>CollectionMemberDeclarationStateObject</code>.
*
* @param parent The parent of this state object, which cannot be <code>null</code>
* @param paths The segments that represent the collection-valued path
* @param identificationVariable The identification variable declaring the collection-valued path
* @exception NullPointerException The given parent cannot be <code>null</code>
*/
public CollectionMemberDeclarationStateObject(AbstractFromClauseStateObject parent,
ListIterator<String> paths,
String identificationVariable) {
this(parent, paths, false, identificationVariable);
}
/**
* Creates a new <code>CollectionMemberDeclarationStateObject</code>.
*
* @param parent The parent of this state object, which cannot be <code>null</code>
* @param collectionValuedPath The derived collection-valued path expression
* @exception NullPointerException The given parent cannot be <code>null</code>
*/
public CollectionMemberDeclarationStateObject(SimpleFromClauseStateObject parent,
String collectionValuedPath) {
super(parent);
this.derived = true;
setPath(collectionValuedPath);
}
/**
* {@inheritDoc}
*/
public void accept(StateObjectVisitor visitor) {
visitor.visit(this);
}
/**
* Makes sure the <code><b>AS</b></code> identifier is specified.
*
* @return This object
*/
public CollectionMemberDeclarationStateObject addAs() {
if (!as) {
setAs(true);
}
return this;
}
/**
* {@inheritDoc}
*/
@Override
protected void addChildren(List<StateObject> children) {
super.addChildren(children);
children.add(collectionValuedPath);
children.add(identificationVariable);
}
/**
* Returns the model object representing the collection-valued association-field
* of an entity abstract schema type.
*
* @return The collection-valued association-field of an entity abstract
* schema type
*/
public CollectionValuedPathExpressionStateObject getCollectionValuedPath() {
return collectionValuedPath;
}
/**
* {@inheritDoc}
*/
@Override
public CollectionMemberDeclaration getExpression() {
return (CollectionMemberDeclaration) super.getExpression();
}
/**
* Returns the model object representing an identification variable
* evaluating to a collection-valued association-field of an entity abstract
* schema type.
*
* @return The identification variable portion of this declaration
*/
public IdentificationVariableStateObject getIdentificationVariable() {
return identificationVariable;
}
/**
* {@inheritDoc}
*/
public IManagedType getManagedType(StateObject stateObject) {
if (identificationVariable.isEquivalent(stateObject)) {
return collectionValuedPath.getManagedType();
}
return null;
}
/**
* {@inheritDoc}
*/
@Override
public AbstractFromClauseStateObject getParent() {
return (AbstractFromClauseStateObject) super.getParent();
}
/**
* Determines whether the <code><b>AS</b></code> identifier is used or not.
*
* @return <code>true</code> if the <code><b>AS</b></code> identifier is part
* of the expression; <code>false</code> otherwise
*/
public boolean hasAs() {
return as;
}
/**
* Determines whether an identification variable was defined.
*
* @return <code>true</code> if an identification variable is defined; <code>false</code> otherwise
*/
public boolean hasIdentificationVariable() {
return identificationVariable.hasText();
}
/**
* {@inheritDoc}
*/
public ListIterable<IdentificationVariableStateObject> identificationVariables() {
return new SingleElementListIterable<IdentificationVariableStateObject>(identificationVariable);
}
/**
* {@inheritDoc}
*/
@Override
protected void initialize() {
super.initialize();
collectionValuedPath = new CollectionValuedPathExpressionStateObject(this);
identificationVariable = new IdentificationVariableStateObject(this);
}
/**
* Determines whether this collection member declaration is used as a derived collection-valued
* path expression.
*
* @return <code>true</code> if this collection member declaration is used as this form:
* "<code><b>IN</b> collection_valued_path_expression</code>" in a subquery; <code>false</code>
* if it's used as this form: <code><b>IN</b>(collection_valued_path_expression)
* [<b>AS</b>] identification_variable</code>" in a top-level or subquery queries
*/
public boolean isDerived() {
return derived;
}
/**
* {@inheritDoc}
*/
@Override
public boolean isEquivalent(StateObject stateObject) {
if (super.isEquivalent(stateObject)) {
CollectionMemberDeclarationStateObject declaration = (CollectionMemberDeclarationStateObject) stateObject;
return as == declaration.as &&
derived == declaration.derived &&
identificationVariable.isEquivalent(declaration.identificationVariable) &&
collectionValuedPath .isEquivalent(declaration.collectionValuedPath);
}
return false;
}
/**
* Makes sure the <code><b>AS</b></code> identifier is not specified.
*/
public void removeAs() {
if (as) {
setAs(false);
}
}
/**
* Sets whether the <code><b>AS</b></code> identifier is used or not.
*
* @param as <code>true</code> if the <code><b>AS</b></code> identifier is part of the expression;
* <code>false</code> otherwise
*/
public void setAs(boolean as) {
boolean oldAs = this.as;
this.as = as;
firePropertyChanged(AS_PROPERTY, oldAs, as);
}
/**
* Sets whether this collection member declaration is used as a derived collection-valued path
* expression.
*
* @param derived <code>true</code> if this collection member declaration is used as this form:
* "<code><b>IN</b> collection_valued_path_expression</code>" in a subquery; <code>false</code>
* if it's used as this form: <code><b>IN</b>(collection_valued_path_expression)
* [<b>AS</b>] identification_variable</code>" in a top-level or subquery queries
*/
public void setDerived(boolean derived) {
this.derived = derived;
}
/**
* Keeps a reference of the {@link CollectionMemberDeclaration parsed object} object, which
* should only be done when this object is instantiated during the conversion of a parsed JPQL
* query into {@link StateObject StateObjects}.
*
* @param expression The {@link CollectionMemberDeclaration parsed object} representing an <code><b>IN</b></code>
* expression
*/
public void setExpression(CollectionMemberDeclaration expression) {
super.setExpression(expression);
}
/**
* Sets the new identification variable that will range over the collection-valued path.
*
* @param identificationVariable The new identification variable
*/
public void setIdentificationVariable(String identificationVariable) {
this.identificationVariable.setText(identificationVariable);
}
/**
* Changes the path expression with the list of segments, the identification variable will also
* be updated with the first segment.
*
* @param path The new path expression
*/
public void setPath(String path) {
collectionValuedPath.setPath(path);
}
/**
* Changes the path expression with the list of segments, the identification variable will also
* be updated with the first segment.
*
* @param paths The new path expression
*/
public void setPaths(List<String> paths) {
collectionValuedPath.setPaths(paths);
}
/**
* Changes the path expression with the list of segments, the identification variable will also
* be updated with the first segment.
*
* @param paths The new path expression
*/
public void setPaths(ListIterator<String> paths) {
collectionValuedPath.setPaths(paths);
}
/**
* Changes the path expression with the list of segments, the identification variable will also
* be updated with the first segment.
*
* @param paths The new path expression
*/
public void setPaths(String... paths) {
collectionValuedPath.setPaths(paths);
}
/**
* Toggles the usage of the <code><b>AS</b></code> identifier.
*/
public void toggleAs() {
setAs(!as);
}
/**
* {@inheritDoc}
*/
@Override
protected void toTextInternal(Appendable writer) throws IOException {
writer.append(IN);
if (!derived) {
writer.append(LEFT_PARENTHESIS);
}
else {
writer.append(SPACE);
}
collectionValuedPath.toString(writer);
if (!derived) {
writer.append(RIGHT_PARENTHESIS);
}
if (!derived) {
writer.append(SPACE);
if (as) {
writer.append(AS);
writer.append(SPACE);
}
identificationVariable.toString(writer);
}
}
}