如何正确设置变量以在布尔值中进行测试？

Question

在我的课堂上，我们分配了一个名为 Battleship 的 CodeHS 作业。我被困在第 7 部分的第 2 部分，即 Location 类。练习如下：

下一个要编写的类是 Location.java 文件。 Location 类存储一个网格位置的信息。

一个位置有两个定义属性

1) 这个位置有船吗？

2) 这个位置的状态是什么？

这个状态会是这个位置是未猜到的，我们是命中还是失败。

public static final int UNGUESSED = 0;
public static final int HIT = 1;
public static final int MISSED = 2;

这些是您需要为 Location 类实现的方法。

// Location constructor. 
public Location()

// Was this Location a hit?
public boolean checkHit()

// Was this location a miss?
public boolean checkMiss()

// Was this location unguessed?
public boolean isUnguessed()

// Mark this location a hit.
public void markHit()

// Mark this location a miss.
public void markMiss()

// Return whether or not this location has a ship.
public boolean hasShip()

// Set the value of whether this location has a ship.
public void setShip(boolean val)

// Set the status of this Location.
public void setStatus(int status)

// Get the status of this Location.
public int getStatus()

而我的工作如下：

public class Location
{
    private int location;
    private int hit;
    private int miss;
    private boolean val;
    private int status;
    //Implement the Location class here
    public static final int UNGUESSED = 0;
    public static final int HIT = 1;
    public static final int MISSED = 2;

    // Location constructor. 
    public Location(int location){
        this.location = location;
    }

// Was this Location a hit?
public boolean checkHit(){
    if(location == HIT)
    return true;
    return false;
}

// Was this location a miss?
public boolean checkMiss(){
    if(location == MISSED)
    return true;
    return false;
}

// Was this location unguessed?
public boolean isUnguessed(){
    if(location == UNGUESSED)
    return true;
    return false;
}

// Mark this location a hit.
public void markHit(int hit){
    this.hit = hit;
}

// Mark this location a miss.
public void markMiss(int miss){
    this.miss = miss;
}

// Return whether or not this location has a ship.
public boolean hasShip(){
    return val;
}

    // Set the value of whether this location has a ship.
   public void setShip(boolean val){
    if(status == HIT)
    val = true;
    else 
    val = false;
}

// Set the status of this Location.
public void setStatus(int status){
    this.status = status;
}

// Get the status of this Location.
public int getStatus(){
    if(status == HIT)
    return HIT;
    else if (status == MISSED)
    return MISSED;
    else if(status == UNGUESSED)
    return UNGUESSED;
}

}

虽然如果我在其他地方出现错误，我真的不会感到惊讶，但我的主要问题是 setShip 布尔方法。我应该如何将其设置为 true（该位置有一艘船）或 false（没有船）。我所拥有的是我最好的猜测，但只有在“射击”之后进行测试时才是正确的。而且我认为该练习希望在此之前对其进行测试。

Answer 1

你有一个私有的布尔值，你用 hasShip() 返回。

您的 setShip(val) 方法应该使用 val 设置类变量，而不是根据统计数据进行计算。

这只是一个简单的setter方法。

编辑：

就像

// Mark this location a hit.
public void markHit(int hit){
    this.hit = hit;
}

Answer 2

首先：不要更改从练习中获得的方法签名（例如，构造函数不应该有参数，markHit 和 markMiss 方法也是如此。

您不需要将int miss 和int hit 保存在两个不同的变量中，因为不能同时命中和错过一个位置，因此我们使用单个变量status。

我很确定你的问题 1 和 2 （或多或少）是同一件事，因为如果有命中，就会有一艘船，反之亦然，所以你只有一个属性 int status = 0，所以每个位置都是 UNCHECKED默认情况下，您可以从那里读取所有内容。

您所要做的就是更改markMiss和markHit方法上的状态变量并相应地调用setShip。

代码示例：

public void markMiss() {
    this.status = MISSED;
    setShip(false);
}

public void markHit() {
    this.status = HIT;
    setShip(true);
}

public boolean checkMiss() {
    return this.status == MISSED;
}

public boolean checkHit() {
    return this.status == HIT;
}

public boolean setShip(boolean val) {
    this.hasAShip = val;
}

public boolean hasShip() {
    return this.hasAShip;
}

Answer 3

感谢各位的帮助。使用提供的反馈，我将课程固定为以下内容，它现在可以工作了。

public class Location
{
    private int status;
    private boolean ship;
    //Implement the Location class here
    public static final int UNGUESSED = 0;
    public static final int HIT = 1;
    public static final int MISSED = 2;

    // Location constructor. 
    public Location(){
        status = UNGUESSED;
        ship = false;
    }

    // Was this Location a hit?
    public boolean checkHit(){
        if(status == HIT)
            return true;
        return false;
    }

    // Was this location a miss?
    public boolean checkMiss(){
        if(status == MISSED)
            return true;
        return false;
    }

    // Was this location unguessed?
    public boolean isUnguessed(){
        if(status == UNGUESSED)
            return true;
        return false;
    }

    // Mark this location a hit.
    public void markHit(){
        status = HIT;
    }

    // Mark this location a miss.
    public void markMiss(){
        status = MISSED;
    }

    // Return whether or not this location has a ship.
    public boolean hasShip(){
        return ship;
    }

    // Set the value of whether this location has a ship.
    public void setShip(boolean val){
        ship = val;
    }

    // Set the status of this Location.
    public void setStatus(int status){
        this.status = status;
    }

    // Get the status of this Location.
    public int getStatus(){
        return status;
    }
}