axiom/include/axiom_child_element_iterator.h

/*
 * 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.
 */
 
 #ifndef AXIOM_CHILD_ELEMENT_ITERATOR_H
 #define AXIOM_CHILD_ELEMENT_ITERATOR_H
 
 /**
 *@file axiom_child_element_iterator.h   
 *@brief this is the iterator for om elemnts 
 */
  
#include <axiom_node.h>
#include <axiom_text.h>
  

#ifdef __cplusplus
extern "C"
{
#endif

typedef struct axiom_child_element_iterator_ops axiom_child_element_iterator_ops_t;
typedef struct axiom_child_element_iterator axiom_child_element_iterator_t;

/**
 * @defgroup axiom_child_element_iterator child element iterator 
 * @ingroup axiom_om
 * @{
 */
 
   /**
    * \brief axiom_child_element_iterator ops
    * Encapsulator struct for ops of axiom_iterator
    */
     struct axiom_child_element_iterator_ops
    {
        axis2_status_t (AXIS2_CALL *free_fn)
                            (void *iterator,
                             const axis2_env_t *env);
                             
        /**
        * Removes from the underlying collection the last element returned by the
        * iterator (optional op).  This method can be called only once per
        * call to <tt>next</tt>.  The behavior of an iterator is unspecified if
        * the underlying collection is modified while the iteration is in
        * progress in any way other than by calling this method.
        */                                              
        axis2_status_t (AXIS2_CALL *
      remove)(axiom_child_element_iterator_t *iterator,
                const axis2_env_t *env);
                             
       /**
        * returns true if the iteration has more elements 
        * in otherwords it returns true if the next() would return an element
        * rather than null with an error code set to environments error
        */                             
        axis2_bool_t (AXIS2_CALL *
      has_next)(axiom_child_element_iterator_t *iterator,
                  const axis2_env_t *env);
    
       /**
        * Returns the next element in the iteration. Returns null if there 
      * is no more elements 
        */
        axiom_node_t* (AXIS2_CALL *
      next)(axiom_child_element_iterator_t *iterator,
              const axis2_env_t *env);
    };
    
    
struct axiom_child_element_iterator
{
    axiom_child_element_iterator_ops_t *ops;
};    

/** 
 * @param current child
 * @param env environment 
 * return axiom_child_element_iterator_t 
 */

AXIS2_EXTERN  axiom_child_element_iterator_t * AXIS2_CALL
axiom_child_element_iterator_create(const axis2_env_t *env, 
                                       axiom_node_t *current_child);
                                  
/************ Macros *********************************************/

#define AXIOM_CHILD_ELEMENT_ITERATOR_FREE(iterator, env) \
        (((axiom_child_element_iterator_t *) iterator)->ops->free_fn(iterator, env))

#define AXIOM_CHILD_ELEMENT_ITERATOR_REMOVE(iterator, env) \
        ((iterator)->ops->remove(iterator, env))
        
#define AXIOM_CHILD_ELEMENT_ITERATOR_HAS_NEXT(iterator, env) \
        ((iterator)->ops->has_next(iterator, env))
        
#define AXIOM_CHILD_ELEMENT_ITERATOR_NEXT(iterator, env) \
        ((iterator)->ops->next(iterator, env))        
        
/** @} */

#ifdef __cplusplus
}
#endif


#endif /* AXIOM_CHILD_ELEMENT_ITERATOR_H */