对象数组实例的深度复制，Java

Question

public class Recipe implements Cloneable{

String Name;

final int INGREDIENT_ARRAY_MAX = 10;

Ingredient Recipe[] = new Ingredient[INGREDIENT_ARRAY_MAX];

public Recipe(String name){

    Name = name;

}

public Object clone(){

    Recipe cloneRec = new Recipe(Name);

    return cloneRec;

}

编辑:@Rohit Jain

我的Recipe类和Ingreatent类（Recipe数组保存的对象）都有toString方法和recipes对Ingreats的调用，以便以一个漂亮的小格式将其全部打印出来。当我在我的“recipeone”对象（即意大利辣香肠披萨）上调用它时，我得到的是“意大利辣香肠披萨：1.0磅面团，8.0盎司酱汁，10.0盎司奶酪”。

然后我继续制作对象ressippi并将其设置为recipeOne的克隆，所以从这里开始一切都很好...然后我将ressippi的名字改为“菠萝披萨”，打印出来很好，但它没有打印recipeOne存储的3个成分对象，这是它应该做的！

Answer 1

向recipe类添加一个copy构造函数，它创建一个新的recipe实例，并从原始recipe复制所有字段。

Recipe.java

public class Recipe implements Cloneable {

    String name;

    final int INGREDIENT_ARRAY_MAX = 10;

    Ingredient[] ingredients = new Ingredient[INGREDIENT_ARRAY_MAX];

    public Recipe(String name) {
        this.name = name;
    }

    //Copy Constructor
    private Recipe(Recipe recipe){
        this.name = recipe.name;
        for(int x = 0; x < recipe.ingredients.length; x++){
            this.ingredients[x] = recipe.ingredients[x];
        }
    }

    public static Recipe newInstance(Recipe recipe){
        return new Recipe(recipe);
    }

    //Debug Method
    public static void printRecipe(Recipe recipe){
        System.out.println("Recipe: " + recipe.name);
        for(Ingredient i:recipe.ingredients){
          if(i != null && i.getName() != null){
              System.out.println("Ingredient: " + i.getName());           
          }
        }
    }

    //Test Method
    public static void main(String[] args) {
        Recipe recipe = new Recipe("Chicken Soup");
        recipe.ingredients[0] = new Ingredient("Chicken");
        recipe.ingredients[1] = new Ingredient("Broth");

        Recipe copy = new Recipe(recipe);
        copy.ingredients[2] = new Ingredient("Rice");
        copy.name = "Chicken Rice Soup";

        printRecipe(recipe);
        printRecipe(copy);
        System.out.println(recipe == copy);
        System.out.println(recipe.ingredients == copy.ingredients);
    }
}

成分.java

public class Ingredient {

    private String name;

    public Ingredient(String name){
        this.name = name;
    }

    public String getName() {
        return name;
    }


    public void setName(String name) {
        this.name = name;
    }
}