/*
* 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 org.teiid.query.QueryPlugin;
import org.teiid.query.sql.lang.PredicateCriteria.Negatable;
import org.teiid.query.sql.symbol.Expression;
/**
* <p>The common functionality of a {@link CompareCriteria} and a
* {@link SubqueryCompareCriteria}. The comparison operators are defined
* here.</p>
*/
public abstract class AbstractCompareCriteria extends PredicateCriteria implements Negatable {
/** Constant indicating the two operands are equal. */
public static final int EQ = 1;
/** Constant indicating the two operands are not equal. */
public static final int NE = 2;
/** Constant indicating the first operand is less than the second. */
public static final int LT = 3;
/** Constant indicating the first operand is greater than the second. */
public static final int GT = 4;
/** Constant indicating the first operand is less than or equal to the second. */
public static final int LE = 5;
/** Constant indicating the first operand is greater than or equal to the second. */
public static final int GE = 6;
/** The left-hand expression. */
private Expression leftExpression;
/**
* The operator used in the clause.
* @see #EQ
* @see #NE
* @see #LT
* @see #GT
* @see #LE
* @see #GE
*/
private int operator = EQ;
/**
* Returns the operator.
* @return The operator
*/
public int getOperator() {
return this.operator;
}
/**
* Sets the operator.
* @param operator
*/
public void setOperator( int operator ) {
if (operator < EQ || operator > GE) {
throw new IllegalArgumentException(QueryPlugin.Util.getString("ERR.015.010.0001", operator)); //$NON-NLS-1$
}
this.operator = operator;
}
/**
* Gets the operator constant given the string version
* @param op Operator, string form
* @return Operator, constant form
*/
public static int getOperator(String op){
if(op.equals("=" )) return EQ; //$NON-NLS-1$
else if(op.equals("<>")) return NE; //$NON-NLS-1$
else if(op.equals("<>")) return NE; //$NON-NLS-1$
else if(op.equals("<" )) return LT; //$NON-NLS-1$
else if(op.equals(">" )) return GT; //$NON-NLS-1$
else if(op.equals("<=")) return LE; //$NON-NLS-1$
else if(op.equals(">=")) return GE; //$NON-NLS-1$
else return -1;
}
/**
* Set left expression.
* @param expression Left expression
*/
public void setLeftExpression(Expression expression) {
this.leftExpression = expression;
}
/**
* Get left expression.
* @return Left expression
*/
public Expression getLeftExpression() {
return this.leftExpression;
}
/**
* Returns the operator as a string.
* @return String version of operator
*/
public String getOperatorAsString() {
switch ( this.operator ) {
case EQ: return "="; //$NON-NLS-1$
case NE: return "<>"; //$NON-NLS-1$
case LT: return "<"; //$NON-NLS-1$
case GT: return ">"; //$NON-NLS-1$
case LE: return "<="; //$NON-NLS-1$
case GE: return ">="; //$NON-NLS-1$
default: return "??"; //$NON-NLS-1$
}
}
@Override
public void negate() {
this.setOperator(getInverseOperator(this.getOperator()));
}
public static int getInverseOperator(int op) {
switch ( op ) {
case EQ: return NE;
case NE: return EQ;
case LT: return GE;
case GT: return LE;
case LE: return GT;
case GE: return LT;
default: return -1;
}
}
} // END CLASS