How to Resolve 'No Properties to Serialize Found' Error in Firebase with Java

What does the error 'No properties to serialize found on class' mean in Firebase, and how can I fix it?

@IgnoreExtraProperties
public class AlumnoFB {
    private String nombre;
    private String apellidos;
    private String telefono;
    private String email;
    ... // other fields
    // Constructors and getters/setters
}

The error 'No properties to serialize found on class' typically occurs in Firebase when the serialization mechanism fails to identify properties in your class. This often relates to the class design or access modifiers, preventing the Firebase SDK from accessing the necessary data to store in the database.

public String getNombre() {
    return nombre;
}

public String getApellidos() {
    return apellidos;
} //... Additional getters for other fields

Causes

• The class does not have public getter methods for its fields.
• The class fields are not accessible due to being private without corresponding getter methods.
• The Firebase SDK is unable to locate any valid properties for serialization.

Solutions

• Ensure that all fields in your class are either public or have public getter methods to provide access.
• Add getter methods for each field in the AlumnoFB class.
• Verify that the @IgnoreExtraProperties annotation is correctly placed to allow Firebase to skip properties that aren't serialized.

Mistake: Not providing public getter methods for private fields.

Solution: Add public getter methods for all fields that should be serialized.

Mistake: Using the wrong annotation placement leading to serialization issues.

Solution: Ensure the @IgnoreExtraProperties annotation is placed correctly on the class definition.