java - Java 中的队列 - 我的实现有什么问题，我可以使用什么？

Question

我正在尝试进行广度优先搜索来解决方 block 移动难题(将方 block 移动到空白空间直到解决的难题)。我的广度优先算法使用队列。不幸的是，它似乎只适用于 UP 和 DOWN 情况，而不适用于 LEFT 或 RIGHT 情况:

                if (up)
            {
                int[][] current = copy(v.state);
                current[x][y] = current[x - 1][y];
                current[x - 1][y] = 0;

                State w = new State(current);
                w.distance = v.distance + 1;
                w.path = v;
                System.out.println(q.insert(w));
            }

            if (down)
            {
                int[][] current = copy(v.state);
                current[x][y] = current[x + 1][y];
                current[x + 1][y] = 0;

                State w = new State(current);
                w.distance = v.distance + 1;
                w.path = v;
                System.out.println(q.insert(w));
            }

            if (left)
            {
                int[][] current = copy(v.state);
                current[x][y] = current[x][y - 1];
                current[x][y - 1] = 0;

                State w = new State(current);
                w.distance = v.distance + 1;
                w.path = v;
                System.out.println(q.insert(w));
            }

            if (right)
            {
                int[][] current = copy(v.state);
                current[x][y] = current[x][y + 1];
                current[x][y + 1] = 0;

                State w = new State(current);
                w.distance = v.distance + 1;
                w.path = v;
                System.out.println(q.insert(w));
            }

我认为这是我的队列的问题，其实现如下。我的队列有问题还是其他问题？ Java API 是否有我可以使用的队列类？

public class ArrayQueue {
State[] items;
int maxSize;
int front;
int rear;
int numItems;

public ArrayQueue(int max)
{
    items = new State[max];
    maxSize = max;
    front = 0;
    rear = -1;
    numItems = 0;
}

public boolean insert(State item)
{
    if (isFull()) return false;
    rear = (rear + 1) % items.length;
    items[rear] = item;
    return true;
}

public State remove()
{
    if (isEmpty()) return null;
    State removed = items[front];
    front = (front + 1) % items.length;
    return removed;
}

public boolean isFull()
{
    if ((front + 1) % maxSize == rear)
        return true;
    else
        return false;
}

public boolean isEmpty()
{
    if ((rear + 1) % maxSize == front)
            return true;
    else
        return false;
}
}

复制方法如下:

public static int[][] copy(int[][] input)       //This method is necessary because we are trying to clone a multi-dimensional array.
{                                               //Just using clone() will copy the outer arrays but they will be arrays of references to the original inner arrays.
int[][] output = new int[input.length][];
for (int i = 0; i < input.length; i++)
    output[i] = input[i].clone();
return output;
}

Answer 1

JDK 提供了Queue 接口(interface)和许多实现，可以在Queue documentation 的“所有已知实现类”部分中找到。 .

为了您的目的，LinkedList应该足够好了。