/**************************************************************************************
* Copyright (C) 2008 EsperTech, Inc. All rights reserved. *
* http://esper.codehaus.org *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
**************************************************************************************/
package com.espertech.esper.client.soda;
import java.io.StringWriter;
/**
* Regular expression evaluates a "regexp" regular expression.
*/
public class RegExpExpression extends ExpressionBase
{
private boolean not;
private static final long serialVersionUID = -3147750744100550487L;
/**
* Ctor - for use to create an expression tree, without child expression.
* @param isNot true for negated regex
*/
public RegExpExpression(boolean isNot)
{
this.not = isNot;
}
/**
* Ctor.
* @param left provides values to match against regexp string
* @param right provides the regexp string
* @param isNot true for negated regex
*/
public RegExpExpression(Expression left, Expression right, boolean isNot)
{
this(left, right, null, isNot);
}
/**
* Ctor.
* @param left provides values to match against regexp string
* @param right provides the regexp string
* @param escape provides the escape character
* @param isNot true for negated regex
*/
public RegExpExpression(Expression left, Expression right, Expression escape, boolean isNot)
{
this.getChildren().add(left);
this.getChildren().add(right);
if (escape != null)
{
this.getChildren().add(escape);
}
this.not = isNot;
}
/**
* Ctor - for use to create an expression tree, without child expression.
*/
public RegExpExpression()
{
not = false;
}
/**
* Ctor.
* @param left provides values to match against regexp string
* @param right provides the regexp string
*/
public RegExpExpression(Expression left, Expression right)
{
this(left, right, null);
}
/**
* Ctor.
* @param left provides values to match against regexp string
* @param right provides the regexp string
* @param escape provides the escape character
*/
public RegExpExpression(Expression left, Expression right, Expression escape)
{
this.getChildren().add(left);
this.getChildren().add(right);
if (escape != null)
{
this.getChildren().add(escape);
}
not = false;
}
public ExpressionPrecedenceEnum getPrecedence() {
return ExpressionPrecedenceEnum.RELATIONAL_BETWEEN_IN;
}
public void toPrecedenceFreeEPL(StringWriter writer) {
this.getChildren().get(0).toEPL(writer, getPrecedence());
if (not)
{
writer.write(" not");
}
writer.write(" regexp ");
this.getChildren().get(1).toEPL(writer, ExpressionPrecedenceEnum.MINIMUM);
if (this.getChildren().size() > 2)
{
writer.write(" escape ");
this.getChildren().get(2).toEPL(writer, ExpressionPrecedenceEnum.MINIMUM);
}
}
/**
* Returns true if negated.
* @return indicator whether negated
*/
public boolean isNot()
{
return not;
}
}