Why Using `success` Instead of `isSuccess` Prevents JSON Serialization Bugs in Java

Background

In everyday development a boolean field is often used to indicate whether a request succeeded, e.g., a success flag exposed through an RPC interface.

JavaBeans Naming Rules

The JavaBeans specification defines getters and setters for normal properties as getPropertyName() and setPropertyName(value). For boolean properties the getter must be named isPropertyName() while the setter remains setPropertyName(boolean).

public <PropertyType> get<PropertyName>();
public void set<PropertyName>(<PropertyType> a);

public boolean is<PropertyName>();
public void set<PropertyName>(boolean m);

Problem When the Field Itself Is Named isSuccess

If a field is declared as private boolean isSuccess;, IDEs often generate a getter named isSuccess() and a setter named setSuccess(boolean). This works at compile time but creates ambiguity for JSON‑serialization libraries that rely on JavaBeans introspection.

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"; }
}

Serialization Differences

The following test serializes a Model instance with three popular libraries.

public class BooleanMainTest {
    public static void main(String[] args) throws IOException {
        Model model = new Model();
        model.setSuccess(true);
        System.out.println("Serializable Result With fastjson :" + JSON.toJSONString(model));
        Gson gson = new Gson();
        System.out.println("Serializable Result With Gson :" + gson.toJson(model));
        ObjectMapper om = new ObjectMapper();
        System.out.println("Serializable Result With jackson :" + om.writeValueAsString(model));
    }
}

Output:

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

fastjson and Jackson discover the isSuccess() method, interpret the property name as success, and therefore produce a JSON field success. Gson, on the other hand, inspects the field directly and emits isSuccess.

Deserialization Mismatch

When the JSON produced by fastjson (or Jackson) is fed back to Gson, Gson looks for a field named success, cannot find it, and leaves the boolean at its default value false:

public class BooleanMainTest {
    public static void main(String[] args) throws IOException {
        Model model = new Model();
        model.setSuccess(true);
        Gson gson = new Gson();
        System.out.println(gson.fromJson(JSON.toJSONString(model), Model.class));
    }
}

Result:

Model[isSuccess=false]

This discrepancy can cause serious production bugs because the object state after a round‑trip is no longer what was originally set.

Recommendation

Define the field as private boolean success; and keep the getter isSuccess(). This follows the JavaBeans convention correctly, yields the same property name ( success) for all serialization frameworks, and eliminates the inconsistency.