Serializable class in secure context

Reports classes that may be serialized or deserialized.

A class may be serialized if it supports the Serializable interface, and its readObject() and writeObject() methods are not defined to always throw an exception. Serializable classes may be dangerous in code intended for secure use.

Example:

  class DeserializableClass implements Serializable { // the class doesn't contain 'writeObject()' method throwing an exception
    private int sensitive = 736326;

    private void readObject(ObjectInputStream in) {
        throw new Error();
    }
}

After the quick-fix is applied:

  class DeserializableClass implements Serializable {
    private int sensitive = 736326;

    private void readObject(ObjectInputStream in) {
        throw new Error();
    }

    private void writeObject(java.io.ObjectOutputStream out) throws java.io.IOException {
        throw new java.io.NotSerializableException("DeserializableClass");
    }
  }

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

-serial

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Java | Security

Use the following options to configure the inspection:

List classes whose inheritors should not be reported by this inspection. This is meant for classes that inherit Serializable from a superclass but are not intended for serialization. Note that it still may be more secure to add readObject() and writeObject() methods which always throw an exception, instead of ignoring those classes.
Whether to ignore serializable anonymous classes.

Inspection options

Here you can find the description of settings available for the Serializable class in secure context inspection, and the reference of their default values.

Ignore subclasses of: Default value:
[java.awt.Component, java.lang.Throwable, java.lang.Enum]
Ignore anonymous classes: Default value:
Not selected

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection -serial

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.2

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.2, Qodana for JVM 2025.2,

Last modified: 18 September 2025