具有浮点类型的 Java getter答案

【问题标题】：Java getter with a float type具有浮点类型的 Java getter
【发布时间】：2022-06-11 01:03:00
【问题描述】：

有人可以解释为什么当我调用具有浮点类型的父类的 getter 时返回为 0？我很确定它与这种数据类型有关，谢谢。

父类

public class BuildingForRent {
    private int buildingDimensions;
    private float advanceAmount;
    
    public BuildingForRent(int buildingDimensions){
        this.buildingDimensions=buildingDimensions;
    }
    
    public float getAdvanceAmount(){
        return this.advanceAmount;
    }
    
    public void setAdvanceAmount(float advanceAmount){
        this.advanceAmount = advanceAmount;
    }
        
    public int getBuildingDimensions(){
        return this.buildingDimensions;
    }
    
    public  void calculateAdvanceAmount(){
        float advanceAmount = -1.0f;
        if(this.buildingDimensions>0){
            advanceAmount=this.buildingDimensions*10;
        }
        this.advanceAmount=advanceAmount;
  }

    @Override
    public String toString() {
        return "BuildingForRent (buildingDimensions=" + this.buildingDimensions
                + ")";
    }
   
}

儿童班

public class ShopForRent extends BuildingForRent{
    char shopType;
    
    public ShopForRent(int buildingDimensions,char shopType){
        super(buildingDimensions);
        this.shopType=shopType;
    }
    
    

    public int identifyShopRent(){
        int shopRent = 0;
        
        switch(this.shopType) {
        case 'A': 
                shopRent = 45000;
                break;
        case 'B':
                shopRent = 30000;
                break;
        case 'C':
                shopRent = 25000;
                break;
        default:
                shopRent = -1;
        
        }
        
        return shopRent;

    }
        
 
    @Override
    public void calculateAdvanceAmount(){
//      float basicAmount = this.getAdvanceAmount();//why this is 0 ??
        float basicAmount = this.getBuildingDimensions() * 10;
        if(this.identifyShopRent() == -1.0f || basicAmount == -1.0f) {
            this.setAdvanceAmount(-1.0f);
        }
        this.setAdvanceAmount(basicAmount + this.identifyShopRent());
    }

    @Override
    public String toString() {
        return "ShopForRent (BuildingForRent (buildingDimensions=" + this.getBuildingDimensions()
                + ")shopType=" + this.shopType + ")";
    }      
}

如您所见，我正在使用类对象调用父 getter，该 getter 正在使用 calculateAmount 函数设置，但是当我从子级调用它时，我无法返回正确的值。

【问题讨论】：

你期望它是什么？您调用setAdvanceAmount 的唯一位置是稍后在同一个函数中，那么您什么时候认为 advanceAmount 实例变量设置为非零值？

标签： java inheritance types