java - 为什么我尝试定义这三个构造函数时会出错？给出的例子

Question

好的，问题是，NetBeans 说第二个已经定义了。这三个是我在顶部的构造函数，列出了整个程序以防 set 或 get 方法是它的错误。所以要明确我在谈论

公共(public)狗(字符串初始名称) 公共(public)狗(字符串初始品种) public Dog(double initialWeight)

错误出现在 public Dog(String initialBreed) 上。我是否滥用了 Overload 方法？我还必须使用强制性的重载方法。

package dog;


import java.util.*;
public class Dog 
{

// instance variables
private String name;
private String breed;
private double weight;

 public Dog( )
{
name = "no name";
breed = "no breed";
weight = 0.0;
}

public Dog(String initialName)
{
name = initialName;
breed = "no breed";
weight = 0.0;
     }

public Dog(String initialBreed){
   name = "no name";
   breed = initialBreed;
   weight = 0.0;
 }
public Dog(double initialWeight){
    name = "no name";
    breed = "no breed";
    weight = initialWeight;
     }


  public void SetDog(String newName, String newBreed, double newWeight) 
  {
   name = newName;
   breed = newBreed;
   if (newWeight <= 0)
      System.out.println("Error: Negative weight.");
   else
       weight = newWeight;
    }
public void setName(String newName){
    name = newName;
}
public void setBreed(String newBreed){
    breed = newBreed;
}
public void setWeight(double newWeight){
    weight = newWeight;
}

public double getWeight(){
     return weight;
}
public String getName(){
     return name;
}
public String getBreed(){
    return breed;
}

Answer 1

问题是你的两个构造函数采用相同的参数:

public Dog(String initialName)

public Dog(String initialBreed){

它们都采用string。不能有两个名称和参数完全相同的方法。

根据我认为您正在尝试做的事情，您可能需要一个包含所有 3 个参数的构造函数:

public Dog(String initialName, String initialBreed, double initialWeight){