/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
package org.teiid.query.sql.lang;
import java.util.Collection;
import org.teiid.core.util.EquivalenceUtil;
import org.teiid.query.sql.LanguageVisitor;
import org.teiid.query.sql.symbol.GroupSymbol;
/**
* A FROM subpart that represents a single group. For example, the FROM clause:
* "FROM a, b" will have two UnaryFromClause objects, each holding a reference to
* a GroupSymbol (for a and b).
*/
public class UnaryFromClause extends FromClause {
private GroupSymbol group;
private Command expandedCommand;
/**
* Construct default object
*/
public UnaryFromClause() {
}
/**
* Construct object with specified group
* @param group Group being held
*/
public UnaryFromClause(GroupSymbol group) {
this.group = group;
}
/**
* Set the group held by the clause
* @param group Group to hold
*/
public void setGroup(GroupSymbol group) {
this.group = group;
}
/**
* Get group held by clause
* @return Group held by clause
*/
public GroupSymbol getGroup() {
return this.group;
}
/**
* Collect all GroupSymbols for this from clause.
* @param groups Groups to add to
*/
public void collectGroups(Collection groups) {
groups.add(this.group);
}
public void acceptVisitor(LanguageVisitor visitor) {
visitor.visit(this);
}
/**
* Check whether objects are equal
* @param obj Other object
* @return True if equal
*/
public boolean equals(Object obj) {
if (!super.equals(obj)) {
return false;
}
if(! (obj instanceof UnaryFromClause)) {
return false;
}
UnaryFromClause other = (UnaryFromClause)obj;
if( (this.getGroup().getDefinition() == null && other.getGroup().getDefinition() == null) ||
(this.getGroup().getDefinition() != null && other.getGroup().getDefinition() != null) ) {
return EquivalenceUtil.areEqual(getGroup(), other.getGroup()) &&
other.isOptional() == this.isOptional();
}
return false;
}
/**
* Get hash code of object
* @return Hash code
*/
public int hashCode() {
if(this.group == null) {
return 0;
}
return this.group.hashCode();
}
/**
* Get deep clone of object
* @return Deep copy of the object
*/
public Object clone() {
GroupSymbol copyGroup = null;
if(this.group != null) {
copyGroup = (GroupSymbol) this.group.clone();
}
UnaryFromClause clonedUnaryFromClause = new UnaryFromClause(copyGroup);
clonedUnaryFromClause.setOptional(this.isOptional());
clonedUnaryFromClause.setMakeDep(this.isMakeDep());
clonedUnaryFromClause.setMakeNotDep(this.isMakeNotDep());
if (this.expandedCommand != null) {
clonedUnaryFromClause.setExpandedCommand((Command)this.expandedCommand.clone());
}
return clonedUnaryFromClause;
}
/**
* @return Returns the expandedCommand.
*/
public Command getExpandedCommand() {
return this.expandedCommand;
}
/**
* @param expandedCommand The expandedCommand to set.
*/
public void setExpandedCommand(Command expandedCommand) {
this.expandedCommand = expandedCommand;
}
}