找不到类型[simple type，com.comcast.ivr.core.domain.AutoHandlingSlotKey]类型的（Map）密钥反序列化器 [英] Can not find a (Map) Key deserializer for type [simple type, class com.comcast.ivr.core.domain.AutoHandlingSlotKey]

问题描述

我有一个具有地图的域对象：

I have a domain object that has a Map:

private Map<AutoHandlingSlotKey, LinkedHashSet<AutoFunction>> autoHandling;

当我序列化对象时，我得到了这个：

When I serialize the object, I get this:

"autoHandling" : [ "java.util.HashMap", {
} ],

这个Map的键是一个自定义对象：

This Map's key is a custom Object:

public class AutoHandlingSlotKey implements Serializable {
    private FunctionalArea slot; // ENUM
    private String returnView;   // ENUM

所以，我不知道如何纠正这个问题，当我反序列化对象：

So, I am not sure how to correct this issue I keep getting when I deserialize the object:

org.codehaus.jackson.map.JsonMappingException: Can not find a (Map) Key deserializer for type [simple type, class com.comcast.ivr.core.domain.AutoHandlingSlotKey]

有人可以帮我理解如果 NOT 有权访问要修改的域对象，请更正此问题？

Can someone help me to understand how to correct this issue if I do NOT have access to the domain object to modify?

推荐答案

按默认情况下，Jackson尝试将Java Maps序列化为JSON对象（键/值对），因此Map键对象必须以某种方式序列化为String;并且必须有匹配（和注册）密钥解串器。默认配置仅支持一小组JDK类型（字符串，数字，枚举）。
因此mapper不知道如何获取String并从中创建AutoHandlingSlotKey。
（实际上我很惊讶序列化器没有因为同样的原因而失败）

By default, Jackson tries to serialize Java Maps as JSON Objects (key/value pairs), so Map key object must be somehow serialized as a String; and there must be matching (and registered) key deserializer. Default configuration only supports a small set of JDK types (String, numbers, enum). So mapper has no idea as to how to take a String and create AutoHandlingSlotKey out of it. (in fact I am surprised that serializer did not fail for same reason)

解决这个问题的两个明显方法是：

Two obvious ways to solve this are:

• 实施并注册密钥解串器


• 为地图实现并注册自定义反序列化器。

在你的情况下，做前者可能更容易。您可能还想实现自定义密钥序列化程序，以确保密钥是正确格式的序列化程序。

In your case it is probably easier to do former. You may also want to implement custom key serializer, to ensure keys are serializer in proper format.

注册序列化程序和反序列化程序的最简单方法是模块接口，在Jackson 1.7中添加（并扩展为1.8以支持关键序列化器/反序列化器）。

The easiest way to register serializers and deserializers is by Module interface that was added in Jackson 1.7 (and extended in 1.8 to support key serializers/deserializers).

这篇关于找不到类型[simple type，com.comcast.ivr.core.domain.AutoHandlingSlotKey]类型的（Map）密钥反序列化器的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！