Feat: Added UserSelect JavaDoc And Junit test

helpmehelpapplication/src/main/java/ntnu/systemutvikling/team6/database/Readers/UserSelect.java

@@ -8,13 +8,49 @@
 import ntnu.systemutvikling.team6.models.user.*;
 import ntnu.systemutvikling.team6.security.PasswordHasher;
 
+/**
+ * Data access class responsible for reading user-related data from the database.
+ *
+ * <p>Provides methods to retrieve individual users (by credentials or UUID),
+ * all users, a user's settings, and a user's inbox. Queries use LEFT JOINs
+ * across the {@code User}, {@code Settings}, and {@code Messages} tables to
+ * assemble fully populated {@link User} objects in a single round trip where
+ * possible.</p>
+ */
+
 public class UserSelect {
+  /** The database connection used for all queries in this class. */
   private final DatabaseConnection connection;
 
+  /**
+   * Constructs a new {@code UserSelect} with the given database connection.
+   *
+   * @param connection the {@link DatabaseConnection} to use for executing queries;
+   *                   must not be {@code null}
+   */
   public UserSelect(DatabaseConnection connection) {
     this.connection = connection;
   }
 
+  /**
+   * Retrieves a single {@link User} from the database matching the given username
+   * and password.
+   *
+   * <p>The password is hashed via {@link PasswordHasher} before being compared
+   * against the stored value. If a matching user is found, their {@link Settings}
+   * (when present) and {@link Inbox} (including any {@link Message} objects) are
+   * also populated. Returns {@code null} if no matching user is found.</p>
+   *
+   * <p><strong>Note:</strong> the current SQL query compares both parameters against
+   * {@code user_password}; the {@code user_name} column is not yet included in the
+   * WHERE clause, which may be a bug.</p>
+   *
+   * @param username the plain-text username to look up
+   * @param password the plain-text password; hashed internally before the query runs
+   * @return the matching {@link User} with settings and inbox populated,
+   *         or {@code null} if no match is found
+   * @throws RuntimeException if a {@link SQLException} occurs while executing the query
+   */
   public User getUserFromDBUsernameAndPassword(String username, String password) {
     PasswordHasher hasher = new PasswordHasher();
     String hashedpassword = hasher.getHashPassword(password);
@@ -83,6 +119,18 @@ public User getUserFromDBUsernameAndPassword(String username, String password) {
     return user;
   }
 
+  /**
+   * Retrieves a single {@link User} from the database by their UUID.
+   *
+   * <p>The returned user is fully populated with {@link Settings} (when present)
+   * and an {@link Inbox} containing any associated {@link Message} objects.
+   * Returns {@code null} if no user with the given UUID exists.</p>
+   *
+   * @param user_id the UUID string of the user to retrieve; must not be {@code null}
+   * @return the matching {@link User} with settings and inbox populated,
+   *         or {@code null} if no user is found
+   * @throws RuntimeException if a {@link SQLException} occurs while executing the query
+   */
   public User getUserFromDBUuid(String user_id) {
     User user = null;
     Connection conn = null;
@@ -146,6 +194,18 @@ public User getUserFromDBUuid(String user_id) {
     return user;
   }
 
+  /**
+   * Retrieves all users from the database, each fully populated with their
+   * {@link Settings} and {@link Inbox}.
+   *
+   * <p>The query LEFT JOINs {@code User}, {@code Settings}, and {@code Messages}.
+   * Multiple rows for the same user UUID (due to multiple messages) are collapsed
+   * into a single {@link User} object with all messages appended to its inbox.</p>
+   *
+   * @return a {@link UserRegistry} containing all users found in the database;
+   *         never {@code null}, but may be empty if no users exist
+   * @throws RuntimeException if a {@link SQLException} occurs while executing the query
+   */
   public UserRegistry getUsersFromDB() {
     UserRegistry registry = new UserRegistry();
     Connection conn = null;
@@ -211,6 +271,17 @@ public UserRegistry getUsersFromDB() {
     return registry;
   }
 
+  /**
+   * Retrieves the {@link Settings} for a specific user by their UUID.
+   *
+   * <p>At most one row is fetched (via {@code setMaxRows(1)}). Returns {@code null}
+   * if no settings row exists for the given user.</p>
+   *
+   * @param user_id the UUID string of the user whose settings should be retrieved;
+   *                must not be {@code null}
+   * @return the user's {@link Settings}, or {@code null} if none are found
+   * @throws RuntimeException if a {@link SQLException} occurs while executing the query
+   */
   public Settings getSettingsForUser(String user_id) {
     Settings settings = null;
     Connection conn = null;
@@ -243,6 +314,19 @@ public Settings getSettingsForUser(String user_id) {
     return settings;
   }
 
+  /**
+   * Retrieves the {@link Inbox} for a specific user by their UUID, populated with
+   * all of their {@link Message} objects.
+   *
+   * <p>Returns an empty {@link Inbox} (never {@code null}) if no messages exist
+   * for the given user.</p>
+   *
+   * @param user_id the UUID string of the user whose inbox should be retrieved;
+   *                must not be {@code null}
+   * @return an {@link Inbox} containing all messages for the user;
+   *         empty if no messages are found
+   * @throws RuntimeException if a {@link SQLException} occurs while executing the query
+   */
   public Inbox getInboxForUser(String user_id) {
     Inbox inbox = new Inbox();
     Connection conn = null;