Apama  10.7.2.2
AP_NormalisedEventIterator_Functions Struct Reference

AP_NormalisedEventIterator_Functions. More...

#include <NormalisedEvent.h>

Public Attributes

AP_bool(* valid )(struct AP_NormalisedEventIterator *it)
 valid More...
 
AP_NormalisedEventKey(* key )(struct AP_NormalisedEventIterator *it)
 key More...
 
AP_NormalisedEventValue(* value )(struct AP_NormalisedEventIterator *it)
 value More...
 
AP_bool(* next )(struct AP_NormalisedEventIterator *it)
 next More...
 
AP_bool(* back )(struct AP_NormalisedEventIterator *it)
 back Move the iterator to the previous element of the underlying normalised event instance. More...
 

Detailed Description

AP_NormalisedEventIterator_Functions.

Table of client visible functions exported by a normalised event iterator (an object used for stepping through the contents of a normalised event in forward or reverse order). These functions declare the only operations that may be performed by users of the normalised event. decoding-specific functions).

Note that all of these functions take an initial AP_NormalisedEventIterator* argument; this is analogous to the (hidden) 'this' pointer passed to a C++ object when a member function is invoked on it.

Member Data Documentation

◆ back

AP_bool(* AP_NormalisedEventIterator_Functions::back) (struct AP_NormalisedEventIterator *it)

back Move the iterator to the previous element of the underlying normalised event instance.

The iterator must be in a valid state (such that the valid() function would return AP_TRUE) before this function is called.

Note that the order in which elements is returned is not necessarily the same as the order in which they were added. The order may change as elements are added to or removed from the underlying event.

Parameters
itThe event iterator instance.
Returns
AP_TRUE if the iterator still points to a valid event element after moving backwards, AP_FALSE otherwise.

◆ key

AP_NormalisedEventKey(* AP_NormalisedEventIterator_Functions::key) (struct AP_NormalisedEventIterator *it)

key

Return the key (name) associated with the current event element pointed to by the iterator. The returned value is owned by the underlying normalised event and should not be modified or freed by the caller.

Parameters
itThe event iterator instance.
Returns
The name of the current normalised event element

◆ next

AP_bool(* AP_NormalisedEventIterator_Functions::next) (struct AP_NormalisedEventIterator *it)

next

Move the iterator to the next element of the underlying normalised event instance. The iterator must be in a valid state (such that the valid() function would return AP_TRUE) before this function is called.

Note that the order in which elements is returned is not necessarily the same as the order in which they were added. The order may change as elements are added to or removed from the underlying event.

Parameters
itThe event iterator instance.
Returns
AP_TRUE if the iterator still points to a valid event element after moving forwards, AP_FALSE otherwise.

◆ valid

AP_bool(* AP_NormalisedEventIterator_Functions::valid) (struct AP_NormalisedEventIterator *it)

valid

Check whether the iterator points to a valid element of the normalised event. Typically used as part of the loop condition when iterating over the contents of an event.

Parameters
itThe event iterator instance.
Returns
AP_TRUE if the iterator points to a valid element, AP_FALSE otherwise.

◆ value

AP_NormalisedEventValue(* AP_NormalisedEventIterator_Functions::value) (struct AP_NormalisedEventIterator *it)

value

Return the value associated with the current event element pointed to by the iterator. The returned value is owned by the underlying normalised event and should not be modified or freed by the caller. The returned value may be an empty string "", or NULL to indicate a missing value.

Parameters
itThe event iterator instance.
Returns
The value of the current normalised event element

The documentation for this struct was generated from the following file: