Sorry for the late reply
Here's the Code:
Recipe using it:
CraftingManager.getInstance().getRecipeList().add(new ShapelessDamageRecipe (new ItemStack(MultiWood),
new Object[] {new ItemStack(Item.pickaxeWood, 1 , -1), new ItemStack(Item.shovelWood, 1 , -1), new ItemStack(Item.axeWood, 1 , -1), new ItemStack(Item.swordWood, 1 , -1),}));