blocks|key|253641|text|这里有一个很好的例子。我使用它来重命名变量，因为JSON来自.Net环境，在该环境中，属性以大写字母开头。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|253642|public+class+Parameter+{
++@JsonProperty("Name")
++public+String+name;
++@JsonProperty("Value")
++public+String+value;+
}|code-block|syntax|javascript|253643|这将正确解析到JSON或从JSON解析：|253644|"Parameter":{
++"Name":"Parameter-Name",
++"Value":"Parameter-Value"
}|253645|entityMap^0|U|4|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

Here's a good example. I use it to rename the variable because the JSON is coming from a <code>.Net</code> environment where properties start with an upper-case letter.

<pre><code>public class Parameter {
 @JsonProperty("Name")
 public String name;
 @JsonProperty("Value")
 public String value; 
}
</code></pre>

This correctly parses to/from the JSON:

<pre><code>"Parameter":{
 "Name":"Parameter-Name",
 "Value":"Parameter-Value"
}
</code></pre>

blocks|key|253663|text|如果没有注释，推断的属性名称(与JSON匹配)将是"set"，而不是"isSet“。这是因为根据Java+Beans规范，"isXxx“和"setXxx”形式的方法被认为意味着有逻辑属性"xxx“需要管理。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|253664|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|$]]

Without annotations, inferred property name (to match from JSON) would be "set", and not -- as seems to be the intent -- "isSet". This is because as per Java Beans specification, methods of form "isXxx" and "setXxx" are taken to mean that there is logical property "xxx" to manage.

blocks|key|470593|text|我认为OldCurmudgeon和StaxMan都是正确的，但这里有一句话的答案和简单的例子。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|470594|@JsonProperty(名称)，告诉Jackson+ObjectMapper将JSON属性名称映射到带注释的Java字段的名称。|470595|//example+of+json+that+is+submitted+
"Car":{
++"Type":"Ferrari",
}

//where+it+gets+mapped+
public+static+class+Car+{
++@JsonProperty("Type")
++public+String+type;
+}|code-block|syntax|javascript|470596|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I think OldCurmudgeon and StaxMan are both correct but here is one sentence answer with simple example for you.

@JsonProperty(name), tells Jackson ObjectMapper to map the JSON property name to the annotated Java field's name.

<pre><code>//example of json that is submitted 
"Car":{
 "Type":"Ferrari",
}

//where it gets mapped 
public static class Car {
 @JsonProperty("Type")
 public String type;
 }
</code></pre>

blocks|key|253695|text|好吧，现在值得了.除了通常的序列化和反序列化之外，JsonProperty还用于为变量指定getter和setter方法。例如，假设您有一个如下的有效负载：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|253696|{
++"check":+true
}|code-block|syntax|javascript|253697|和一个反序列化程序类：|253698|public+class+Check+{

++@JsonProperty("check")++++//+It+is+needed+else+Jackson+will+look+got+getCheck+method+and+will+fail
++private+Boolean+check;

++public+Boolean+isCheck()+{
+++++return+check;
++}
}|253699|然后，在这种情况下，需要JsonProperty注释。但是，如果类中也有一个方法|253700|public+class+Check+{

++//@JsonProperty("check")++++Not+needed+anymore
++private+Boolean+check;

++public+Boolean+getCheck()+{
+++++return+check;
++}
}|253701|也可以看看这个文档：http://fasterxml.github.io/jackson-annotations/javadoc/2.3.0/com/fasterxml/jackson/annotation/JsonProperty.html|offset|length|253702|entityMap|0|LINK|mutability|MUTABLE|url|http://fasterxml.github.io/jackson-annotations/javadoc/2.3.0/com/fasterxml/jackson/annotation/JsonProperty.html^0|0|0|0|0|0|0|A|33|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|11|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|12|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|13|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|14|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|15|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|16|8|@]|9|@$Q|17|R|18|1|19]]|A|$]]|$1|S|3|-4|5|6|7|1A|8|@]|9|@]|A|$]]]|T|$U|$5|V|W|X|A|$Y|Z]]]]

well for what its worth now... JsonProperty is ALSO used to specify getter and setter methods for the variable apart from usual serialization and deserialization. For example suppose you have a payload like this:

<pre><code>{
 "check": true
}
</code></pre>

and a Deserializer class:

<pre><code>public class Check {

 @JsonProperty("check") // It is needed else Jackson will look got getCheck method and will fail
 private Boolean check;

 public Boolean isCheck() {
 return check;
 }
}
</code></pre>

Then in this case JsonProperty annotation is neeeded. However if you also have a method in the class 

<pre><code>public class Check {

 //@JsonProperty("check") Not needed anymore
 private Boolean check;

 public Boolean getCheck() {
 return check;
 }
}
</code></pre>

Have a look at this documentation too: 
<a href="http://fasterxml.github.io/jackson-annotations/javadoc/2.3.0/com/fasterxml/jackson/annotation/JsonProperty.html" rel="noreferrer">http://fasterxml.github.io/jackson-annotations/javadoc/2.3.0/com/fasterxml/jackson/annotation/JsonProperty.html</a>

blocks|key|470647|text|添加JsonProperty还可以确保安全性，以防有人决定更改其中一个属性名称，而没有意识到相关类将被序列化为Json对象。如果他们更改了属性名称，JsonProperty将确保它将在Json对象中使用，而不是属性名称。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|470648|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 the JsonProperty also ensures safety in case someone decides they want to change one of the property names not realizing the class in question will be serialized to a Json object. If they change the property name the JsonProperty ensures it will be used in the Json object, and not the property name.

This bean 'State' :

<pre><code>public class State {

 private boolean isSet;

 @JsonProperty("isSet")
 public boolean isSet() {
 return isSet;
 }

 @JsonProperty("isSet")
 public void setSet(boolean isSet) {
 this.isSet = isSet;
 }

}
</code></pre>

is sent over the wire using the ajax ' success' callback : 

<pre><code> success : function(response) { 
 if(response.State.isSet){ 
 alert('success called successfully)
 }
</code></pre>

Is the annotation @JsonProperty required here ? What is the advantage of using it ?
I think I can remove this annotation without causing any side effects.

Reading about this annotion on <a href="https://github.com/FasterXML/jackson-annotations/wiki/Jackson-Annotations" rel="noreferrer">https://github.com/FasterXML/jackson-annotations/wiki/Jackson-Annotations</a> I don't know when this is required to be used ?

When is the @JsonProperty property used and what is it used for?

这个bean 'State‘：public class State {    private boolean isSet;    @JsonProperty("isSet")    public boolean isSet() {        return isSet;    }    @JsonProperty("...

问什么时候使用@JsonProperty属性，它的用途是什么？
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