/*
 * 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 org.apache.xerces.xs;

/**
 * This interface represents the Model Group schema component.
 */
public interface XSModelGroup extends XSTerm {
    // Content model compositors
    /**
     * This constant value signifies a sequence operator.
     */
    public static final short COMPOSITOR_SEQUENCE       = 1;
    /**
     * This constant value signifies a choice operator.
     */
    public static final short COMPOSITOR_CHOICE         = 2;
    /**
     * This content model represents a simplified version of the SGML 
     * &amp;-Connector and is limited to the top-level of any content model. 
     * No element in the all content model may appear more than once.
     */
    public static final short COMPOSITOR_ALL            = 3;

    /**
     * [compositor]: one of all, choice or sequence. The valid constant values 
     * are: 
     * <code>COMPOSITOR_SEQUENCE, COMPOSITOR_CHOICE, COMPOSITOR_ALL</code>. 
     */
    public short getCompositor();

    /**
     *  A list of [particles] if it exists, otherwise an empty 
     * <code>XSObjectList</code>. 
     */
    public XSObjectList getParticles();

    /**
     * An annotation if it exists, otherwise <code>null</code>. If not null
     * then the first [annotation] from the sequence of annotations.
     */
    public XSAnnotation getAnnotation();

    /**
     * A sequence of [annotations] or an empty <code>XSObjectList</code>.
     */
    public XSObjectList getAnnotations();    
}
