/*
* 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.ArrayList;
import java.util.Collection;
import java.util.LinkedHashSet;
import org.teiid.core.util.EquivalenceUtil;
import org.teiid.core.util.HashCodeUtil;
import org.teiid.query.sql.LanguageObject;
import org.teiid.query.sql.LanguageVisitor;
import org.teiid.query.sql.symbol.Expression;
/**
* A criteria which is true is the expression's value is a member in a list
* of values. This criteria can be represented as "<expression> IN (<expr>, ...)".
*/
public class SetCriteria extends AbstractSetCriteria {
/** The set of value expressions */
private Collection values;
private boolean allConstants;
/**
* Constructs a default instance of this class.
*/
public SetCriteria() {}
/**
* Constructs an instance of this class with the membership expression and value expressions
* @param expression The membership expression
* @param values The set of value {@link org.teiid.query.sql.symbol.Expression}s
*/
public SetCriteria( Expression expression, Collection values ) {
set(expression,values);
}
/**
* Returns the number of values in the set.
* @return Number of values in set
*/
public int getNumberOfValues() {
return (this.values != null) ? this.values.size() : 0;
}
/**
* Returns the set of values. Returns an empty collection if there are
* currently no values.
* @return The collection of Expression values
*/
public Collection getValues() {
return this.values;
}
/**
* Sets the values in the set.
* @param values The set of value Expressions
*/
public void setValues( Collection values ) {
this.values = values;
}
/**
* Sets the membership expression and the set of value expressions
* @param expression The membership expression
* @param values The set of value expressions
*/
public void set( Expression expression, Collection values ) {
setExpression(expression);
setValues(values);
}
public void acceptVisitor(LanguageVisitor visitor) {
visitor.visit(this);
}
/**
* Get hash code. WARNING: The hash code is based on data in the criteria.
* If data values are changed, the hash code will change - don't hash this
* object and change values.
* @return Hash code
*/
public int hashCode() {
int hc = 0;
hc = HashCodeUtil.hashCode(hc, getExpression());
// The expHashCode method walks the set of values, combining
// the hash code at every power of 2: 1,2,4,8,... This is
// much quicker than calculating hash codes for ALL values
hc = HashCodeUtil.expHashCode(hc, getValues());
return hc;
}
/**
* Override equals() method.
* @param obj Other object
* @return True if equal
*/
public boolean equals(Object obj) {
// Use super.equals() to check obvious stuff and variable
if(obj == this) {
return true;
}
if(! (obj instanceof SetCriteria)) {
return false;
}
SetCriteria sc = (SetCriteria)obj;
if (isNegated() ^ sc.isNegated()) {
return false;
}
return getValues().size() == sc.getValues().size() &&
getValues().containsAll(sc.getValues()) &&
EquivalenceUtil.areEqual(getExpression(), sc.getExpression());
}
/**
* Deep copy of object
* @return Deep copy of object
*/
public Object clone() {
Expression copy = null;
if(getExpression() != null) {
copy = (Expression) getExpression().clone();
}
Collection copyValues = null;
if (isAllConstants()) {
copyValues = new LinkedHashSet(values);
} else {
copyValues = LanguageObject.Util.deepClone(new ArrayList(values), Expression.class);
}
SetCriteria criteriaCopy = new SetCriteria(copy, copyValues);
criteriaCopy.setNegated(isNegated());
criteriaCopy.allConstants = allConstants;
return criteriaCopy;
}
public boolean isAllConstants() {
return allConstants;
}
public void setAllConstants(boolean allConstants) {
this.allConstants = allConstants;
}
} // END CLASS