blocks|key|1704414|text|如果你使用的是Spring+Boot，你可以在application.properties文件中设置以下属性。spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1704415|entityMap^0|1J|1I|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

If you are using Spring Boot, you can set the following property in application.properties file.
<code>spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false</code>

blocks|key|1703884|text|如果你的类不包含任何公共方法/属性，你也会遇到同样的问题。我通常对API请求和响应有专门的DTO，声明为公共，但在一种情况下忘记了将方法也设为公共的-这首先导致了“空”bean。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1703885|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

You can also get the same issue if your class doesn't contain any public methods/properties. I normally have dedicated DTOs for API requests and responses, declared public, but forgot in one case to make the methods public as well - which caused the "empty" bean in the first place.

blocks|key|1704539|text|如果你想在没有任何额外字段的情况下获得JSON对象-请在你的类中添加这个注解，它对我来说是完美的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1704540|@JsonIgnoreProperties({"hibernateLazyInitializer",+"handler"})|code-block|syntax|javascript|1704541|您也可以在application.properties文件中添加此行，但这将为您的JSON添加一个额外的字段。|1704542|spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false|1704543|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

If you wish to get JSON object without any extra fields - please add this annotation to your class, it worked perfect for me.

<pre><code>@JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
</code></pre>

You can also add in your application.properties file this row, but it will add an extra field to your JSON.

<pre><code>spring.jackson.serialization.FAIL_ON_EMPTY_BEANS=false
</code></pre>

blocks|key|1703956|text|还可以使用@JsonIgnoreProperties(ignoreUnknown=true)对类进行注释，以忽略类中未定义的字段|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1703957|entityMap^0|5|15|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

You can also probably annotate the class with <code>@JsonIgnoreProperties(ignoreUnknown=true)</code> to ignore the fields undefined in the class

blocks|key|1704769|text|在Jersey+Rest+Services中，只需使用JacksonFeatures注释...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1704770|@JacksonFeatures(serializationDisable+=+{SerializationFeature.FAIL_ON_EMPTY_BEANS})
public+Response+getSomething()+{
++++Object+entity+=+doSomething();
++++return+Response.ok(entity).build();
}|code-block|syntax|javascript|1704771|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In Jersey Rest Services just use the JacksonFeatures annotation ...

<pre><code>@JacksonFeatures(serializationDisable = {SerializationFeature.FAIL_ON_EMPTY_BEANS})
public Response getSomething() {
 Object entity = doSomething();
 return Response.ok(entity).build();
}
</code></pre>

blocks|key|1704021|text|在我的例子中，我遗漏了在导致这个错误的一个字段中编写@JsonProperty注释。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1704022|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

In my case, I missed to write @JsonProperty annotation in one of the fields which was causing this error.

blocks|key|1917566|text|如果您使用的是org.codehaus.jackson.map.ObjectMapper，那么请使用。使用以下几行|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1917567|mapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS,+false);|code-block|syntax|javascript|1917568|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If you use org.codehaus.jackson.map.ObjectMapper, then pls. use the following lines

<pre><code>mapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS, false);
</code></pre>

blocks|key|1917847|text|要解决此问题，请按如下方式配置JsonDataFormat类|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1917848|ObjectMapper+mapper+=+new+ObjectMapper();
mapper.disable(SerializationFeature.FAIL_ON_EMPTY_BEANS);|code-block|syntax|javascript|1917849|这几乎相当于，|1917850|mapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS,+false);|1917851|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

T o fix this issue configure your JsonDataFormat class like below

<pre><code>ObjectMapper mapper = new ObjectMapper();
mapper.disable(SerializationFeature.FAIL_ON_EMPTY_BEANS);
</code></pre>

which is almost equivalent to,

<pre><code>mapper.configure(SerializationConfig.Feature.FAIL_ON_EMPTY_BEANS, false);
</code></pre>

blocks|key|1704207|text|在这里为不同的问题添加解决方案，但出现相同错误的解决方案...在动态构造json+(作为api响应或其他任何东西)时要小心，以转义字符串成员中的文字双引号。您可能正在使用自己的格式错误的json。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1704208|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Adding a solution here for a different problem, but one that manifests with the same error... Take care when constructing json on the fly (as api responses or whatever) to escape literal double quotes in your string members. You may be consuming your own malformed json.

blocks|key|1705054|text|我不完全理解这个异常背后的原因，但是对于Spring+Boot项目来说，将以下内容添加到属性文件中是一种享受|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1705055|application.yml|1705056|spring:
++jackson:
+++serialization:
+++++FAIL_ON_EMPTY_BEANS:+false|code-block|syntax|javascript|1705057|application.properties|1705058|spring.jackson.serialization.FAIL_ON_EMPTY_BEANS+=+false|1705059|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

I don't fully understand the reason behind this exception, but for Spring Boot projects adding the following to the properties file works a treat
application.yml
<pre><code>spring:
 jackson:
 serialization:
 FAIL_ON_EMPTY_BEANS: false
</code></pre>
application.properties
<pre><code>spring.jackson.serialization.FAIL_ON_EMPTY_BEANS = false
</code></pre>

blocks|key|1704850|text|在我的例子中，我不需要禁用它，而是必须将以下代码放在类的顶部：(这解决了我的问题)|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1704851|++++@JsonNaming(PropertyNamingStrategy.SnakeCaseStrategy.class)//this+is+what+was+added
++++@Value+//this+was+there+already
++++@Builder//this+was+there+already

public+class+NameOfClass+{
+++++//some+code+in+here.
}|code-block|syntax|javascript|1704852|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

In my case I didnt need to disable it , rather I had to put this code on top of my class : (and this solved my issue)
<pre><code> @JsonNaming(PropertyNamingStrategy.SnakeCaseStrategy.class)//this is what was added
 @Value //this was there already
 @Builder//this was there already

public class NameOfClass {
 //some code in here.
}
</code></pre>

blocks|key|1705034|text|如果是Spring+App，只需将代码粘贴到config类中|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1705035|++++++++@Bean
++++++++public+ObjectMapper+getJacksonObjectMapper()+{
++++++++++++ObjectMapper+objectMapper+=+new+ObjectMapper();
++++++++++++objectMapper.findAndRegisterModules();
++++++++++++objectMapper.configure(
++++++++++++++++++++com.fasterxml.jackson.databind.SerializationFeature.WRITE_DATES_AS_TIMESTAMPS,+false);
++++++++++++objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
++++++++++++objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES,+false);
++++++++++++return+objectMapper;
++++++++}|code-block|syntax|javascript|1705036|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

If it is a Spring App, just paste the code in config class
<pre><code> @Bean
 public ObjectMapper getJacksonObjectMapper() {
 ObjectMapper objectMapper = new ObjectMapper();
 objectMapper.findAndRegisterModules();
 objectMapper.configure(
 com.fasterxml.jackson.databind.SerializationFeature.WRITE_DATES_AS_TIMESTAMPS, false);
 objectMapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
 objectMapper.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false);
 return objectMapper;
 }
 
</code></pre>

Using jackson 2.1, how do I disable the <code>fail_on_empty beans</code> that the error message seems to want me to disable? 

I'm assuming this is just the simplest thing in the world, but hell it is late and I haven't been able to find a simple tutorial or anything particularly obvious from the <code>api</code>. <code>SerializationFactory</code>? Why would they make it so unintuitive and then make the error message seem so straightforward?

Although I do like the error message, I mean, it is better than an NPE.

I'm assuming there is a way to do this using annotations - but I'm not keen on using them at all for the simplistic work I'm doing!

How do I disable fail_on_empty_beans in Jackson?

在使用jackson 2.1时，我如何禁用错误消息似乎希望我禁用的fail_on_empty beans？我假设这只是世界上最简单的事情，但见鬼，为时已晚，我还没有从api中找到简单的教程或任何特别明显的东西。SerializationFactory？为什么他们让它变得如此不直观，然后让错误消息看起来如此直截了当？虽然我确实喜欢错误消息，但我的意思是，它比NPE更好。我假设有一种方法可以使用注释来

问如何在杰克逊中禁用fail_on_empty_beans？
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问如何在杰克逊中禁用fail_on_empty_beans？
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