src/main/java/cofh/api/item/IToolHammer.java

package cofh.api.item;

import net.minecraft.entity.Entity;
import net.minecraft.entity.EntityLivingBase;
import net.minecraft.item.ItemStack;
import net.minecraft.util.math.BlockPos;

/**
 * Implement this interface on subclasses of Item to have that item work as a tool for CoFH mods.
 */
public interface IToolHammer {

	/**
	 * Called to ensure that the tool can be used on a block.
	 *
	 * @param item
	 *            The ItemStack for the tool. Not required to match equipped item (e.g., multi-tools that contain other tools).
	 * @param user
	 *            The entity using the tool.
	 * @param pos
	 *            Coordinates of the block.
	 * @return True if this tool can be used.
	 */
	boolean isUsable(ItemStack item, EntityLivingBase user, BlockPos pos);

	/**
	 * Called to ensure that the tool can be used on an entity.
	 *
	 * @param item
	 *            The ItemStack for the tool. Not required to match equipped item (e.g., multi-tools that contain other tools).
	 * @param user
	 *            The entity using the tool.
	 * @param entity
	 *            The entity the tool is being used on.
	 * @return True if this tool can be used.
	 */
	boolean isUsable(ItemStack item, EntityLivingBase user, Entity entity);

	/**
	 * Callback for when the tool has been used reactively.
	 *
	 * @param item
	 *            The ItemStack for the tool. Not required to match equipped item (e.g., multi-tools that contain other tools).
	 * @param user
	 *            The entity using the tool.
	 * @param pos
	 *            Coordinates of the block.
	 */
	void toolUsed(ItemStack item, EntityLivingBase user, BlockPos pos);

	/**
	 * Callback for when the tool has been used reactively.
	 *
	 * @param item
	 *            The ItemStack for the tool. Not required to match equipped item (e.g., multi-tools that contain other tools).
	 * @param user
	 *            The entity using the tool.
	 * @param entity
	 *            The entity the tool is being used on.
	 */
	void toolUsed(ItemStack item, EntityLivingBase user, Entity entity);

}