/*
 * reserved comment block
 * DO NOT REMOVE OR ALTER!
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
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package com.sun.org.apache.xerces.internal.impl.xs.models;

import com.sun.org.apache.xerces.internal.xni.QName;
import com.sun.org.apache.xerces.internal.impl.xs.SubstitutionGroupHandler;
import com.sun.org.apache.xerces.internal.impl.xs.XMLSchemaException;

import java.util.Vector;
import java.util.ArrayList;

/**
 * Note: State of the content model is stored in the validator
 *
 * @xerces.internal 
 *
 * @author Sandy Gao, IBM
 * @author Elena Litani, IBM
 * @version $Id: XSCMValidator.java,v 1.6 2009/07/28 15:18:12 spericas Exp $
 */
public interface XSCMValidator {


    public static final short FIRST_ERROR = -1;

    // on subsequent errors the validator should not report
    // an error
    //
    public static final short SUBSEQUENT_ERROR = -2;

    /**
     * This methods to be called on entering a first element whose type
     * has this content model. It will return the initial state of the content model
     *
     * @return Start state of the content model
     */
    public int[] startContentModel();


    /**
     * The method corresponds to one transaction in the content model.
     *
     * @param elementName
     * @param state  Current state
     * @return element decl or wildcard decl that
     *         corresponds to the element from the Schema grammar
     */
    public Object oneTransition (QName elementName, int[] state, SubstitutionGroupHandler subGroupHandler);


    /**
     * The method indicates the end of list of children
     *
     * @param state  Current state of the content model
     * @return true if the last state was a valid final state
     */
    public boolean endContentModel (int[] state);

    /**
     * check whether this content violates UPA constraint.
     *
     * @param subGroupHandler the substitution group handler
     * @return true if this content model contains other or list wildcard
     */
    public boolean checkUniqueParticleAttribution(SubstitutionGroupHandler subGroupHandler) throws XMLSchemaException;

    /**
     * Check which elements are valid to appear at this point. This method also
     * works if the state is in error, in which case it returns what should
     * have been seen.
     * 
     * @param state  the current state
     * @return       a Vector whose entries are instances of
     *               either XSWildcardDecl or XSElementDecl.
     */
    public Vector whatCanGoHere(int[] state);

    /**
     * Used by constant space algorithm for a{n,m} for n > 1 and
     * m <= unbounded. Called by a validator if validation of
     * countent model succeeds after subsuming a{n,m} to a*
     * (or a+) to check the n and m bounds.
     * Returns <code>null</code> if validation of bounds is
     * successful. Returns a list of strings with error info
     * if not. Even entries in list returned are error codes
     * (used to look up properties) and odd entries are parameters
     * to be passed when formatting error message. Each parameter
     * is associated with the error code that preceeds it in
     * the list.
     */
    public ArrayList checkMinMaxBounds();
    
} // XSCMValidator
