Package edu.wpi.first.util

Class CircularBuffer<T>

java.lang.Object
edu.wpi.first.util.CircularBuffer<T>
Type Parameters:
T - Buffer element type.
public class CircularBuffer<T>
extends Object
This is a simple circular buffer so we don't need to "bucket brigade" copy old values.

  • Constructor Summary

    Constructors 
    Constructor Description
    CircularBuffer​(int size)
    Create a CircularBuffer with the provided size.

  • Method Summary

    Modifier and Type Method Description
    void addFirst​(T value)
    Push new value onto front of the buffer.
    void addLast​(T value)
    Push new value onto back of the buffer.
    void clear()
    Sets internal buffer contents to zero.
    T get​(int index)
    Get the element at the provided index relative to the start of the buffer.
    T getFirst()
    Get value at front of buffer.
    T getLast()
    Get value at back of buffer.
    T removeFirst()
    Pop value at front of buffer.
    T removeLast()
    Pop value at back of buffer.
    void resize​(int size)
    Resizes internal buffer to given size.
    int size()
    Returns number of elements in buffer.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • CircularBuffer

      public CircularBuffer​(int size)
      Create a CircularBuffer with the provided size.
      Parameters:
      size - Maximum number of buffer elements.

  • Method Details

    • size

      public int size()
      Returns number of elements in buffer.
      Returns:
      number of elements in buffer

    • getFirst

      public T getFirst()
      Get value at front of buffer.
      Returns:
      value at front of buffer

    • getLast

      public T getLast()
      Get value at back of buffer.
      Returns:
      value at back of buffer
      Throws:
      IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())

    • addFirst

      public void addFirst​(T value)
      Push new value onto front of the buffer. The value at the back is overwritten if the buffer is full.
      Parameters:
      value - The value to push.

    • addLast

      public void addLast​(T value)
      Push new value onto back of the buffer. The value at the front is overwritten if the buffer is full.
      Parameters:
      value - The value to push.

    • removeFirst

      public T removeFirst()
      Pop value at front of buffer.
      Returns:
      value at front of buffer
      Throws:
      IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())

    • removeLast

      public T removeLast()
      Pop value at back of buffer.
      Returns:
      value at back of buffer
      Throws:
      IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size())

    • resize

      public void resize​(int size)
      Resizes internal buffer to given size.

      A new buffer is allocated because arrays are not resizable.

      Parameters:
      size - New buffer size.

    • clear

      public void clear()
      Sets internal buffer contents to zero.

    • get

      public T get​(int index)
      Get the element at the provided index relative to the start of the buffer.
      Parameters:
      index - Index into the buffer.
      Returns:
      Element at index starting from front of buffer.