com.sun.msv.grammar.ExpressionCloner Maven / Gradle / Ivy
/*
* Copyright (c) 2001-2013 Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.sun.msv.grammar;
/**
* clones an expression.
*
*
* By visiting an expression, returns a cloned expression.
*
*
* This class is useless by itself since expressions are shared and unified.
* It should be used as a base class for various AGM-related tasks to modify
* AGM.
*
*
* Note that this class doesn't provide default implementations for
* onAttribute, onElement, and onRef methods.
* Typically, the derived class needs to do something to prevent infinite recursion.
*
* @author Kohsuke KAWAGUCHI
*/
public abstract class ExpressionCloner implements ExpressionVisitorExpression {
protected final ExpressionPool pool;
protected ExpressionCloner( ExpressionPool pool ) { this.pool = pool; }
public Expression onChoice( ChoiceExp exp ) {
Expression np1 = exp.exp1.visit(this);
Expression np2 = exp.exp2.visit(this);
if(exp.exp1==np1 && exp.exp2==np2) return exp;
else return pool.createChoice(np1,np2);
}
public Expression onOneOrMore( OneOrMoreExp exp ) {
Expression np = exp.exp.visit(this);
if(exp.exp==np) return exp;
else return pool.createOneOrMore(np);
}
public Expression onMixed( MixedExp exp ) {
Expression body = exp.exp.visit(this);
if(exp.exp==body) return exp;
else return pool.createMixed( body );
}
public Expression onList( ListExp exp ) {
Expression body = exp.exp.visit(this);
if(exp.exp==body) return exp;
else return pool.createList( body );
}
public Expression onSequence( SequenceExp exp ) {
Expression np1 = exp.exp1.visit(this);
Expression np2 = exp.exp2.visit(this);
if(exp.exp1==np1 && exp.exp2==np2) return exp;
else return pool.createSequence(np1,np2);
}
public Expression onConcur( ConcurExp exp ) {
return pool.createConcur(
exp.exp1.visit(this), exp.exp2.visit(this));
}
public Expression onInterleave( InterleaveExp exp ) {
return pool.createInterleave(
exp.exp1.visit(this), exp.exp2.visit(this));
}
public Expression onEpsilon() { return Expression.epsilon; }
public Expression onNullSet() { return Expression.nullSet; }
public Expression onAnyString() { return Expression.anyString; }
public Expression onData( DataExp exp ) { return exp; }
public Expression onValue( ValueExp exp ) { return exp; }
}