The Simple Item Lib is a Library wich allows to easily add eventlistener by a Consumer to the ItemStack ( Items are identified by 64char random string set in ItemMeta ) or you can set your own custom keys when using static Items
SimpleItemBuilder builder = new SimpleItemBuilder(Material.IRON_AXE);
builder.addItemFlag(ItemFlag.HIDE_ATTRIBUTES);
builder.setClickHandler(event -> {
event.getWhoClicked().sendMessage("You have clicked the Item");
});
SimpleItemStack itemStack = builder.build();