/*

 */

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You 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.

 */

package com.sun.org.apache.xerces.internal.impl.xs.models;

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

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

import java.util.ArrayList;

/**

 * XSEmptyCM is a derivative of the abstract content model base class that

 * handles a content model with no chilren (elements).

 *

 * This model validated on the way in.

 *

 * @xerces.internal

 *

 * @author Elena Litani, Lisa Martin

 * @author IBM

 */

public class XSEmptyCM  implements XSCMValidator {

    //

    // Constants

    //

    // start the content model: did not see any children

    private static final short STATE_START = 0;

    //

    // Data

    //

    //

    // XSCMValidator methods

    //

    /**

     * 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(){

        return (new int[] {STATE_START});

    }

    /**

     * The method corresponds to one transaction in the content model.

     *

     * @param elementName the qualified name of the element

     * @param currentState Current state

     * @param subGroupHandler the substitution group handler

     * @return element index corresponding to the element from the Schema grammar

     */

    public Object oneTransition (QName elementName, int[] currentState, SubstitutionGroupHandler subGroupHandler){

        // error state

        if (currentState[0] < 0) {

            currentState[0] = XSCMValidator.SUBSEQUENT_ERROR;

            return null;

        }

        currentState[0] = XSCMValidator.FIRST_ERROR;

        return null;

    }

    /**

     * The method indicates the end of list of children

     *

     * @param currentState Current state of the content model

     * @return true if the last state was a valid final state

     */

    public boolean endContentModel (int[] currentState){

        boolean isFinal =  false;

        int state = currentState[0];

        // restore content model state:

        // error

        if (state < 0) {

            return false;

        }

        return true;

    }

    /**

     * 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 {

        return false;

    }

    /**

     * 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 list whose entries are instances of

     *               either XSWildcardDecl or XSElementDecl.

     */

        return EMPTY;

    }

        return null;

    }

    public int [] occurenceInfo(int[] state) {

        return null;

    }

    public String getTermName(int termId) {

        return null;

    }

    public boolean isCompactedForUPA() {

        return false;

    }

} // class XSEmptyCM