/*
* Copyright (c) 1998-2010 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.relaxng.pattern;
import com.caucho.relaxng.RelaxException;
import com.caucho.relaxng.program.ChoiceItem;
import com.caucho.relaxng.program.EmptyItem;
import com.caucho.relaxng.program.Item;
import com.caucho.util.CharBuffer;
import java.util.ArrayList;
/**
* Relax element pattern
*/
public class ChoicePattern extends Pattern {
private ArrayList<Pattern> _patterns = new ArrayList<Pattern>();
private boolean _hasEmpty;
private Item _item;
/**
* Creates a new choice pattern.
*/
public ChoicePattern()
{
}
/**
* Returns the number of children.
*/
public int getSize()
{
return _patterns.size();
}
/**
* Returns the n-th child.
*/
public Pattern getChild(int i)
{
return _patterns.get(i);
}
public boolean hasEmpty()
{
return _hasEmpty;
}
/**
* Returns true if it contains a data element.
*/
public boolean hasData()
{
for (int i = 0; i < _patterns.size(); i++) {
if (_patterns.get(i).hasData())
return true;
}
return false;
}
/**
* Returns true if it contains a data element.
*/
public boolean hasElement()
{
for (int i = 0; i < _patterns.size(); i++) {
if (_patterns.get(i).hasElement())
return true;
}
return false;
}
/**
* Adds an element.
*/
public void addChild(Pattern child)
throws RelaxException
{
child.setElementName(getElementName());
if (child instanceof ChoicePattern) {
ChoicePattern list = (ChoicePattern) child;
if (list._hasEmpty)
_hasEmpty = true;
for (int i = 0; i < list.getSize(); i++)
addChild(list.getChild(i));
return;
}
if (child instanceof EmptyPattern) {
_hasEmpty = true;
return;
}
if (! _patterns.contains(child))
_patterns.add(child);
}
/**
* Returns the Relax schema name.
*/
public String getTagName()
{
return "choice";
}
/**
* Creates the production item.
*/
public Item createItem(GrammarPattern grammar)
throws RelaxException
{
if (_item == null) {
ChoiceItem item = new ChoiceItem();
for (int i = 0; i < _patterns.size(); i++) {
item.addItem(_patterns.get(i).createItem(grammar));
}
if (_hasEmpty)
item.addItem(EmptyItem.create());
_item = item.getMin();
}
return _item;
}
/**
* Returns a string for the production.
*/
public String toProduction()
{
if (_hasEmpty && _patterns.size() == 1)
return "(" + _patterns.get(0).toProduction() + ")?";
CharBuffer cb = new CharBuffer();
if (_hasEmpty)
cb.append("(");
for (int i = 0; i < _patterns.size(); i++) {
if (i != 0)
cb.append(" | ");
cb.append(_patterns.get(i).toProduction());
}
if (_hasEmpty)
cb.append(")?");
return cb.toString();
}
public boolean equals(Object o)
{
if (this == o)
return true;
if (! (o instanceof ChoicePattern))
return false;
ChoicePattern choice = (ChoicePattern) o;
if (_hasEmpty != choice._hasEmpty)
return false;
if (_patterns.size() != choice._patterns.size())
return false;
return isSubset(choice) && choice.isSubset(this);
}
private boolean isSubset(ChoicePattern item)
{
if (_patterns.size() != item._patterns.size())
return false;
for (int i = 0; i < _patterns.size(); i++) {
Pattern subPattern = _patterns.get(i);
if (! item._patterns.contains(subPattern))
return false;
}
return true;
}
/**
* Debugging.
*/
public String toString()
{
return "ChoicePattern" + _patterns;
}
}