Why Using isSuccess Can Break JSON Serialization in Java and How to Fix It

In daily development we often define boolean fields in classes, e.g., a field indicating whether a request succeeded.

Developers use different naming conventions such as

success

or

isSuccess

, and IDEs often generate

isSuccess

getters automatically.

According to the JavaBeans Specification, a normal property

propertyName

has getters/setters

getPropertyName()

and

setPropertyName(...)

. For boolean properties the getter is

isPropertyName()

and the setter remains

setPropertyName(...)

.

<code>public &lt;PropertyType&gt; get&lt;PropertyName&gt;();
public void set&lt;PropertyName&gt;(&lt;PropertyType&gt; a);
</code>

For a boolean property the signatures become:

<code>public boolean is&lt;PropertyName&gt;();
public void set&lt;PropertyName&gt;(boolean m);
</code>

If the property is named

success

, the getter should be

isSuccess

(or

getSuccess

) and the setter

setSuccess

. If the property itself is named

isSuccess

, the getter would be

isIsSuccess

or

getIsSuccess

, which is confusing.

Consider the following JavaBean:

<code>class Model implements Serializable {
    private static final long serialVersionUID = 1836697963736227954L;
    private boolean isSuccess;

    public boolean isSuccess() { return isSuccess; }
    public void setSuccess(boolean success) { isSuccess = success; }
    public String getHollis() { return "hollischuang"; }
}
</code>

When this class is serialized with different JSON libraries, the results differ:

<code>Serializable Result With fastjson :{"hollis":"hollischuang","success":true}
Serializable Result With Gson :{"isSuccess":true}
Serializable Result With jackson :{"success":true,"hollis":"hollischuang"}
</code>

Fastjson and Jackson inspect getter methods, treat

isSuccess

as a property named

success

, and therefore output

"success"

. Gson, on the other hand, inspects fields directly and outputs the original field name

"isSuccess"

.

Consequently, if an object serialized by fastjson (or Jackson) is deserialized by Gson, the

isSuccess

field will be missing and default to

false

, which can cause serious bugs in production.

To avoid this inconsistency, the recommendation is to name the field

success

and keep the getter

isSuccess

. This follows the JavaBeans convention and yields identical results across all major JSON serialization frameworks.