ItemTickThingy

ItemTimer.java

public class ItemTimer extends Item
{
  //This is the identifier for the NBT tag that will store the time
  private static String TIMER_TAG = "Timer";
  //This is the delay we want to have between actions. It is in game ticks, 1 game tick is equal to 1/20 of asecond.
  private static int DELAY = 5;
  
  //Standard item init stuff
  public ItemTimer()
  {
    this.setUnlocalizedName("mod.timer");
    this.setTextureName("mod:timer")
  }
  
  @Override
  onUpdate(ItemStack stack, World world, Entity entity, int invSlot, boolean isInHand)
  {
    //if the timer has reached DELAY, perform the action and set the timer to 0...
    if(ItemTimer.getTimer(stack) == DELAY)
    {
      //Do stuff here
      ItemTimer.setTimer(stack, 0);
    }
    //...otherwise, increment it
    else
    {
      ItemTimer.incrementTimer(stack);
    }
  }
  
  //This method returns the current value of the timer
  private static int getTimer(ItemStack stack)
  {
    //if the stack doesn't have an NBT tag yet, give it one
    if (stack.stackTagCompound == null) stack.stackTagCompound = new NBTTagCompound();
    return stack.stackTagCompound.getInteger(TIMER_TAG);
  }
  
  //This method sets the current value of the timer
  private static void setTimer(ItemStack stack, int value)
  {
    //if the stack doesn't have an NBT tag yet, give it one
    if (stack.stackTagCompound == null) stack.stackTagCompound = new NBTTagCompound();
    stack.stackTagCompound.setInteger(TIMER_TAG, value);
  }
  
  //This method increments the current value of the timer by 1
  private static void incrementTimer(ItemStack stack)
  {
    ItemTimer.setTimer(stack, ItemTimer.getTimer(stack) + 1);
  }
}