Interface Counter<T extends Comparable<T>>

Type Parameters:
T - The type of value that is counted.
All Known Subinterfaces:
Counter.LongCounter
public interface Counter<T extends Comparable<T>>
A generic interface for objects that keep a count, using a value from a discrete domain.

  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Interface
    Description
    static interface 
    Counter.LongCounter
    A special Counter for Long values.

  • Method Summary

    Modifier and Type
    Method
    Description
    default void
    changeBy(long amount)
    Changes the counter by the specific amount of units.
    default T
    changeByAndGet(long amount)
    Changes the counter by the specific amount of units and returns the new value.
    T
    current()
    Get the current value of the counter.
    default void
    decrement()
    Decrements the counter by a single unit.
    default T
    decrementAndGet()
    Decrements the counter by a single unit and returns the new value.
    com.google.common.collect.DiscreteDomain<T>
    domain()
    Gets the domain discrete domain to which the counter value belongs.
    default T
    getAndChangeBy(long amount)
    Gets the current value of the counter, then changes the counter by the specific amount of units.
    default T
    getAndDecrement()
    Gets the current value of the counter, then decrements the counter by a single unit.
    default T
    getAndIncrement()
    Gets the current value of the counter, then increments the counter by a single unit.
    default void
    increment()
    Increments the counter by a single unit.
    default T
    incrementAndGet()
    Increments the counter by a single unit and returns the new value.
    void
    set(T value)
    Sets the counter to a specific value.

  • Method Details

    • changeBy

      default void changeBy(long amount)
      Changes the counter by the specific amount of units. A positive amount increments the counter, a negative amount decrements the counter.

      The default implementation of this method is to increment or decrement the counter by repeatedly incrementing or decrementing the counter by a single unit via the domain until the desired amount is reached. Implementations are encouraged to override this method with a more efficient implementation if possible.

      Parameters:
      amount - The amount to change the counter by.

    • changeByAndGet

      default T changeByAndGet(long amount)
      Changes the counter by the specific amount of units and returns the new value.
      Parameters:
      amount - The amount to change the counter by.
      Returns:
      The new value of the counter after it was changed.

    • current

      T current()
      Get the current value of the counter.
      Returns:
      The current value of the counter.

    • decrement

      default void decrement()
      Decrements the counter by a single unit.

    • decrementAndGet

      default T decrementAndGet()
      Decrements the counter by a single unit and returns the new value.
      Returns:
      The new value of the counter after decrementing.

    • domain

      com.google.common.collect.DiscreteDomain<T> domain()
      Gets the domain discrete domain to which the counter value belongs.
      Returns:
      The domain of the counter value.

    • getAndChangeBy

      default T getAndChangeBy(long amount)
      Gets the current value of the counter, then changes the counter by the specific amount of units.
      Parameters:
      amount - The amount to change the counter by.
      Returns:
      The previous value of the counter.

    • getAndDecrement

      default T getAndDecrement()
      Gets the current value of the counter, then decrements the counter by a single unit.
      Returns:
      The previous value of the counter.

    • getAndIncrement

      default T getAndIncrement()
      Gets the current value of the counter, then increments the counter by a single unit.
      Returns:
      The previous value of the counter.

    • increment

      default void increment()
      Increments the counter by a single unit.

    • incrementAndGet

      default T incrementAndGet()
      Increments the counter by a single unit and returns the new value.
      Returns:
      The new value of the counter after incrementing.

    • set

      void set(T value)
      Sets the counter to a specific value.
      Parameters:
      value - The value to set the counter to.