content: /*
   * Section.java November 2010
   *
   * Copyright (C) 2010, Niall Gallagher <niallg@users.sf.net>
   *
   * 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.
   */
  
  package com.aliyun.odps.simpleframework.xml.core;
  
  /**
   * The <code>Section</code> interface is used to represent a section
   * of XML that is to be generated. A section is a tree structure in
   * that it can contain other sections. Each section contains the
   * elements and attributes associated with it. This is used so that
   * complex XML structures can be written for a single object.
   * <p>
   * For convenience all the element names, including other section
   * names, can be iterated over. Element and section names can be
   * differentiated using the source section.
   * 
   * @author Niall Gallagher
   * 
   * @see Structure
   */
  interface Section extends Iterable<String> {
     
     /**
      * This is used to return the name of the section. The name is 
      * must be a valid XML element name. It is used when a style
      * is applied to a path as the section name must be styled.
      * 
      * @return this returns the name of this section instance
      */
     String getName();
     
     /**
      * This is used to acquire the path prefix for the section. The
      * path prefix is used when the section is transformed in to an
      * XML structure. This ensures that the XML element created to
      * represent the section contains the optional prefix.
      * 
      * @return this returns the prefix for this section
      */
     String getPrefix();
  
     /**
      * This is used to acquire the text label for this section if 
      * one has been specified. A text label can only exist in a
      * section if there are no elements associated with the section
      * and the section is not composite, as in it does not contain
      * any further sections.
      * 
      * @return this returns the text label for this section
      */
     Label getText() throws Exception; 
  
     /**
      * Returns a <code>LabelMap</code> that contains the details for
      * all fields and methods marked with XML annotations. All of the
      * element annotations are considered and gathered by name in 
      * this map. Also, if there is an associated <code>Style</code> 
      * for serialization the element names are renamed with this.
      * 
      * @return returns the elements associated with this section
      */
     LabelMap getElements() throws Exception;
     
     /**
      * Returns a <code>LabelMap</code> that contains the details for
      * all fields and methods marked with XML annotations. All of the
      * attribute annotations are considered and gathered by name in 
      * this map. Also, if there is an associated <code>Style</code> 
      * for serialization the attribute names are renamed with this.
      * 
      * @return returns the attributes associated with this section
      */
     LabelMap getAttributes() throws Exception;
     
     /**
      * Returns the named element as a <code>Label</code> object.
      * For convenience this method is provided so that when iterating
      * over the names of the elements in the section a specific one
      * of interest can be acquired.
      * <p>
      * To ensure that elements of the same name are not referenced
      * more than once this will remove the element once acquired. 
      * This ensures that they are visited only once in serialization.      
      * 
      * @param name the name of the element that is to be acquired
      * 
      * @return this returns the label associated with the name
      */
     Label getElement(String name) throws Exception;
     
     /**
      * Returns the named section as a <code>Section</code> object.
      * For convenience this method is provided so that when iterating
      * over the names of the elements in the section a specific one
      * of interest can be acquired. 
      * <p>
      * To ensure that models of the same name are not referenced
      * more than once this will remove the model once acquired. 
      * This ensures that they are visited only once in serialization.
      * 
      * @param name the name of the element that is to be acquired
      * 
      * @return this returns the section associated with the name
      */
     Section getSection(String name) throws Exception;
     
     /**
      * This is used to acquire the full element path for this
      * section. The element path is simply the fully qualified
      * path for this expression with the provided name appended.
      * If this is an empty path, the provided name is returned.
      * 
      * @param name this is the name of the element to be used
      * 
      * @return a fully qualified path for the specified name
      */
     String getPath(String name) throws Exception;
     
     /**
      * This is used to acquire the full attribute path for this 
      * section. The attribute path is simply the fully qualified
      * path for this expression with the provided name appended.
      * If this is an empty path, the provided name is returned.
      * 
      * @param name this is the name of the attribute to be used
      * 
      * @return a fully qualified path for the specified name
      */
     String getAttribute(String name) throws Exception;
     
     /**
      * To differentiate between a section and an element this can be
      * used. When iterating over the elements within the section the
      * names of both elements and sections are provided. So in order
      * to determine how to interpret the structure this can be used.
      * 
      * @param name this is the name of the element to be determined
      * 
      * @return this returns true if the name represents a section
      */
     boolean isSection(String name) throws Exception;
  }
  