大小在哪里获得它的价值(Java)

Question

从哪个"int size"获得它的价值？我读了1000次代码,但我仍然不知道"size"初始化的地方,我是java的新手,但我不明白这一点,代码工作正常任何帮助都会很好.提前致谢

public class Study {
  public static void main(String[] args) {
    Queue queue = new Queue();
    for (int i = 0; i <= 20; i++)
      queue.enqueue(i);

    while (!queue.empty())
      System.out.print(queue.dequeue() + " ");
  }
}

class Queue {
  private int[] elements;
  private int size;

  public Queue() {
    elements = new int[8];
  }

  public void enqueue(int value) {
    if (size >= elements.length) {
      int[] temp = new int[elements.length * 2];
      System.arraycopy(elements, 0, temp, 0, elements.length);
      System.out.println(elements.length);
      elements = temp;
    }

    elements[size++] = value;
  }

  public int dequeue() {
    int v = elements[0];

    // Shift all elements in the array left
    for (int i = 0; i < size - 1; i++) {
      elements[i] = elements[i + 1];
    }

    size--;

    return v;
  }

  public boolean empty() {
    return size == 0;
  }

  public int getSize() {
    return size;
  }
}

Answer 1

默认值是0对int.

并size++和size--正在做的更改它的价值.

有关更多信息,请参阅:赋值,算术和一元运算符