public static PDAction createAction(COSDictionary action) 
{
        PDAction retval = null;
        if( action != null )
        {
            String type = action.getNameAsString( "S" );
            if( PDActionJavaScript.SUB_TYPE.equals( type ) )
            {
                retval = new PDActionJavaScript( action );
            }
            else if( PDActionGoTo.SUB_TYPE.equals( type ) )
            {
                retval = new PDActionGoTo( action );
            }
            else if( PDActionLaunch.SUB_TYPE.equals( type ) )
            {
                retval = new PDActionLaunch( action );
            }
            else if( PDActionRemoteGoTo.SUB_TYPE.equals( type ) )
            {
                retval = new PDActionRemoteGoTo( action );
            }
            else if( PDActionURI.SUB_TYPE.equals( type ) )
            {
                retval = new PDActionURI( action );
            }
        }
        return retval;
}

This will create the correct type of action based on the type specified in the dictionary.