This advanced [JSup] feature enable a [JSup Channels|I/O Channel] to get its I/O hooks from a [JavaCode functions|JavaCode function] that will decide which tag (for instance based according to the tag class) will be bound to which device item and if in read/write only mode.

The [JavaCode functions|JavaCode function] must accept an unique parameter: <TT>ChannelInfo ch</TT>
And must return an <TT><code>Iterable<IOHookCodeCreatedInfo></code></TT> object.
Its signature should be:
<TT><code>Iterable<IOHookCodeCreatedInfo> </code>''functionName''<code>( ChannelInfo ch ) throws JException;</code></TT>

The [JavaCode functions|JavaCode function] can determine which tag to include be enumerating the tags that belong to a certain [JSup Tag classes|tag class]. The following example provides MQTT I/O hook for the tag of [JSup Tag classes|tag class] named <TT>/device/onoff</TT>:
<code>final Vector<IOHookCodeCreatedInfo> v = new Vector<>();
for( final TagRef tag : getTagClass( "/device/onoff" ).tags() ) {
  v.add( new IOHookCodeCreatedInfo.N.Adapter(
     tag, "/JSupTest/device/onoff/"+tag.getName(), true, false, null, null, false )
  );
}
</code>

An [JSup Channels|I/O Channel] can have both [IOHook|I/O hooks] statically entered in the [JSup Tag dialog|tag dialog] and JavaCode function provided ones.

The name of the [JavaCode functions|JavaCode function] that will provide [IOHook|I/O hooks] to a channel have to be specified in the ''Auto I/O hook JavaCode fun:'' in the [JSup Channels#Channel configuration|I/O channel dialog] dialog.