com.sun.msv.grammar.util.NameClassComparator Maven / Gradle / Ivy
/*
* @(#)$Id: NameClassComparator.java,v 1.2 2004/01/26 18:55:33 kohsuke Exp $
*
* Copyright 2001 Sun Microsystems, Inc. All Rights Reserved.
*
* This software is the proprietary information of Sun Microsystems, Inc.
* Use is subject to license terms.
*
*/
package com.sun.msv.grammar.util;
import com.sun.msv.grammar.AnyNameClass;
import com.sun.msv.grammar.ChoiceNameClass;
import com.sun.msv.grammar.DifferenceNameClass;
import com.sun.msv.grammar.NameClass;
import com.sun.msv.grammar.NameClassVisitor;
import com.sun.msv.grammar.NamespaceNameClass;
import com.sun.msv.grammar.NotNameClass;
import com.sun.msv.grammar.SimpleNameClass;
/**
* Abstract implementation of a function
*
* NameClass x NameClass -> boolean
*
*
* Override the probe method to define the actual function.
*
*
*
* To compute, create an instance and call the check method. This class is not
* reentrant, so the caller is responsible not to reuse the same object by multiple
* threads.
*
* @author Kohsuke KAWAGUCHI
*/
public abstract class NameClassComparator implements NameClassVisitor {
/** Two name classes to be tested. */
protected NameClass nc1,nc2;
/**
* This exception will be thrown when a collision is found.
*/
protected final RuntimeException eureka = new RuntimeException();
/**
* Returns true if two name classes collide.
*/
public boolean check( NameClass _new, NameClass _old ) {
try {
nc1 = _new;
nc2 = _old;
_old.visit(this);
_new.visit(this);
return false;
} catch( RuntimeException e ) {
if(e==eureka) return true; // the collision was found.
throw e;
}
}
/**
* Throw eureka to return true from the probe method.
*/
protected abstract void probe( String uri, String local );
private /*static*/ final String MAGIC = "\u0000";
public Object onAnyName( AnyNameClass nc ) {
probe(MAGIC,MAGIC);
return null;
}
public Object onNsName( NamespaceNameClass nc ) {
probe(nc.namespaceURI,MAGIC);
return null;
}
public Object onSimple( SimpleNameClass nc ) {
probe(nc.namespaceURI,nc.localName);
return null;
}
public Object onNot( NotNameClass nc ) {
nc.child.visit(this);
return null;
}
public Object onDifference( DifferenceNameClass nc ) {
nc.nc1.visit(this);
nc.nc2.visit(this);
return null;
}
public Object onChoice( ChoiceNameClass nc ) {
nc.nc1.visit(this);
nc.nc2.visit(this);
return null;
}
}