Question

我想反序列化以下JSON：

{
  "name":"Test",
  "owners":[
    {
      "username":"admin"
    }
  ]
}

关注对象

public class ShoppingList {

  private String name;
  private final Set<ShoppingListUser> owners;

  public String getName() {

    return name;
  }

  public void setName(String name) {

    this.name = name;
  }

  public Set<ShoppingListUser> getOwners() {

    return owners;
  }

  @JsonDeserialize(as = HashSet.class, contentAs = ShoppingListUser.class)
  public void setOwners(Set<ShoppingListUser> owners) {

    getOwners().clear();

    if (owners != null) {
        getOwners().addAll(owners);
    }
  }
}

我的控制器看起来像这样：

@RestController
@RequestMapping(value = "/api/shoppingLists", consumes = "application/json", produces = "application/json")
public class ShoppingListController {

@RequestMapping(method = RequestMethod.POST)
public ResponseEntity<Resource<ShoppingList>> addShoppingList(@RequestBody ShoppingList shoppingList)
    throws ShoppingListException {
  //DoStuff
}

所有者的类型为 ShoppingListUser ：

public class ShoppingListUser {

  private String username;

  private String password;

  //Getters and Setters
}

我的问题是当我使用给定的JSON向此控制器发送一个后请求时，响应将是：

{＆＃34; timestamp＆＃34;：1435965015546，＆＃34; status＆＃34;：400，＆＃34; error＆＃34;：＆＃34; Bad Request＆＃34;，＆＃34; exception＆＃34;：＆＃34; org.springframework.http.converter.HttpMessageNotReadableException＆＃34;，＆＃34; message＆＃34;：＆＃34;无法读取JSON：模板不能为空或空！（通过参考链：de.klem.shopping.list.ShoppingList [\＆＃34; owner \＆＃34;] - ＆gt; java.util.LinkedHashSet [0]）;嵌套异常是com.fasterxml.jackson.databind.JsonMappingException：模板不能为null或为空！（通过参考链：de.klem.shopping.list.ShoppingList [\＆＃34; owner \＆＃34;] - ＆gt; java.util.LinkedHashSet [0]）＆＃34;，＆＃34; path＆＃ 34;：＆＃34; / API / shoppingLists＆＃34;}

我不了解事件为何在此异常中发生LinkedHashSet。我没有告诉杰克逊使用HashSet.class来反序集吗？

有人看到我的错误吗？我不能:(

要获得完整的代码，请随时访问我的github repo：https://github.com/Yannic92/ShoppingList/blob/master/src/main/java/de/klem/shopping/list/ShoppingList.java

运行应用程序所需的只是Maven和Java。

git clone https://github.com/Yannic92/ShoppingList.git
cd ShoppingList
mvn clean spring-boot：run
将给定的JSON发布到localhost：8080 / api / shoppingLists

user：admin

密码：密码

Spring @RestController - 用一组对象反序列化对象作为字段（杰克逊）

0 个答案: