为字段名维护单独常量的替代方法

public enum FieldName {
    FIRST_NAME,
    LAST_NAME,
    EMAIL,
    PHONE_NUMBER
}

public class User {
    private String firstName;
    private String lastName;
    private String email;
    private String phoneNumber;

    // 使用枚举常量作为字段名
    public void setFieldValue(FieldName fieldName, String value) {
        switch (fieldName) {
            case FIRST_NAME:
                this.firstName = value;
                break;
            case LAST_NAME:
                this.lastName = value;
                break;
            case EMAIL:
                this.email = value;
                break;
            case PHONE_NUMBER:
                this.phoneNumber = value;
                break;
            default:
                throw new IllegalArgumentException("Invalid field name: " + fieldName);
        }
    }
}