当我通过 Postman 发布一个新的实体时，一切正常，我得到的答案是：

{
    "id": 3,
    "ingredients": [
        "Eggs",
        "Oil"
    ]
}

但是，当我试图获取数据库中现有的实体时，listcomponents返回为“null”：

[
    {
        "id": 3,
        "ingredients": null
    }
]

这是我的模型：

package com.petie.weeklyrecipesschedule.model;

import javax.persistence.*;
import java.util.List;

@Entity
public class Recipe {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private long id;
    private String name;
    @Embedded
    private List<String> ingredients;

    protected Recipe() {}

    public Recipe(String name, List<String> ingredients) {
        this.name = name;
        this.ingredients = ingredients;
    }

    //Getters and setters
    //toString()
}

我的存储库

package com.petie.weeklyrecipesschedule.repository;

import com.petie.weeklyrecipesschedule.model.Recipe;
import org.springframework.data.jpa.repository.JpaRepository;

public interface RecipeRepository extends JpaRepository<Recipe, Long> {
}

还有我的控制器

package com.petie.weeklyrecipesschedule.controller;

import com.petie.weeklyrecipesschedule.model.Recipe;
import com.petie.weeklyrecipesschedule.repository.RecipeRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

@RestController
@RequestMapping("/recipes")
public class RecipeController {

    @Autowired
    private RecipeRepository recipeRepository;

    public RecipeController(RecipeRepository recipeRepository) {
        this.recipeRepository = recipeRepository;
    }

    @GetMapping("/all")
    List<Recipe> getAll() {
        return recipeRepository.findAll();
    }

    @PostMapping("/post")
    Recipe newRecipe(@RequestBody Recipe recipe) {
        return recipeRepository.save(recipe);
    }
}

至于依赖关系，我使用的是springweb、springjpa和h2数据库。