java - 如何制作具有动态值的@JSONProperty？

Question

我想要生成以下 JSON 输出。

**JSON Output:**
{
  "ingredients": {
    "main": ["flour", "water", "egg"],
    "optional": ["olives", "salami"]
  }
}

我尝试创建以下类，但执行以下操作时遇到一些困难:

1. 如何创建动态 JSONProperty，如“主要”和“可选”可以是动态值。
2. 如何返回字符串数组？

3. 我的做法正确吗？

     public class Pizza {
         private Ingredients[] fIngredients;
   
         @JsonProperty("ingredients")
         public Ingredients[] getIngredients() { return fIngredients; }
   
         public void setIngredients(Ingredients ingredients) { fIngredients = ingredients; }
       }
   
       public class Ingredients {
         private String[] fFoods;
   
         @JsonProperty("????") // how do i put a dynamic name here?
         public String[] getFoods() { return fFoods; }
   
         public void addFoods(List<String> foodsList) {
           String[] array = foodsList.toArray(foodsList.size());
               fFoods = ArrayUtils.addAll(fFoods, array);
         }
       }
   

Answer 1

为了拥有动态属性，您可以为属性使用Map类型。所以你可以有这样的代码:

public class Pizza {
    private Map<String, List<String>> ingredients = new HashMap();

    public Map<String, List<String>> getIngredients() {
        return ingredients;
    }

    public void addIngredient(String name, List<String> values) {
        ingredients.put(name, values);
    }

    public static void main(String[] args) {
        Pizza pizza = new Pizza();
        pizza.addIngredient("main", Arrays.asList("flour", "water", "egg"));
        pizza.addIngredient("optional", Arrays.asList("olives", "salami"));

        ObjectMapper mapper = new ObjectMapper();
        System.out.println(mapper.writeValueAsString(pizza));
    }
}