@JsonIgnore

@JsonIgnore — a Jackson annotation used to exclude a field or method from JSON serialization or deserialization.

🧩 Purpose

Prevents sensitive or unnecessary data from appearing in JSON responses or being read from incoming JSON.

Example:

public class User {
    private String username;

    @JsonIgnore
    private String password;

    // getters & setters
}

public class User {
    private String username;

    @JsonIgnore
    private String password;

    // getters & setters
}

✅ When serialized:

{
  "username": "john"
}

{
  "username": "john"
}

The password field is ignored — not included in the output or parsed from input.

🧠 Key Points

• Comes from com.fasterxml.jackson.annotation.
• Can be applied to fields or getters/setters.
• If you need conditional control, use @JsonIgnoreProperties or @JsonInclude.