Updated DatabaseManager

Added JavaDocs and printStackTrace to createCharitiesTable method.

helpmehelpapplication/src/main/java/ntnu/sytemutvikling/team6/models/DatabaseManager.java

@@ -3,12 +3,34 @@
 import java.sql.*;
 import java.util.List;
 
+/**
+ * Manages creation and synchronization of database tables in a MySQL database.
+ * <p>
+ * This class is responsible for establishing connections using environment variables
+ * and maintaining the {@code charities} table based on data retrieved from the IK API.
+ * </p>
+ */
+
 public class DatabaseManager {
-    // Database environment is MySQL
     private final String databaseURL;
     private final String username;
     private final String password;
 
+    /**
+     Constructs a new {@code DatabaseManager} using database credentials
+     * retrieved from system environment variables.
+     * <p>
+     * Required environment variables:
+     * <ul>
+     *     <li>{@code HMH_DB_URL}</li>
+     *     <li>{@code HMH_DB_USERNAME}</li>
+     *     <li>{@code HMH_DB_PASSWORD}</li>
+     * </ul>
+     * </p>
+     *
+     * @throws IllegalStateException if either databaseURL, username, or password is {@code null} or blank
+     */
+
     // Values stored in system environment variables for security (using ntnu's phpmyadmin for this project)
     public DatabaseManager() {
         this.databaseURL = System.getenv("HMH_DB_URL");
@@ -28,8 +50,15 @@ public DatabaseManager() {
         }
     }
 
+    /**
+     * Creates the {@code charities} table if it does not already exist.
+     * <p>
+     * The table structure is based on fields from {@link APICharityData}.
+     * </p>
+     * @throws RuntimeException if a {@link SQLException} occurs while creating the table
+     */
+
     public void createCharitiesTable() {
-        // Creates table if it doesn't exist
         String sql_create_main_table = """
                 CREATE TABLE IF NOT EXISTS charities (
                 org_number VARCHAR(100) PRIMARY KEY,
@@ -44,12 +73,28 @@ url VARCHAR(255),
 
             s.execute(sql_create_main_table);
         } catch (SQLException e) {
+            e.printStackTrace();
             throw new RuntimeException("Error creating tables.");
         }
     }
 
+    /**
+     * Synchronizes the {@code charities} table with the provided list of APICharityData.
+     * <p>
+     * Summary of function:
+     * <ul>
+     *     <li>Inserts new records</li>
+     *     <li>Updates existing records using {@code ON DUPLICATE KEY UPDATE}</li>
+     *     <li>Removes database records that are not present in the provided list</li>
+     * </ul>
+     * A temporary table is used to determine which records should be deleted.
+     * </p>
+     *
+     * @param charities a list of ApiCharityDaya objects
+     * @throws RuntimeException if a {@link SQLException} occurs during database synchronization
+     */
+
     public void updateCharities(List<APICharityData> charities) {
-        // Inserts values in APICharityData to table
 
         try (Connection conn = DriverManager.getConnection(databaseURL, username, password))
              {
@@ -77,17 +122,15 @@ INSERT INTO charities (org_number, name, status, url, is_pre_approved)
             }
             s.executeBatch();
 
-             // Removed temp table used for parity check
+             // Temporary table for parity check
             String sql_drop_temp_table = "DROP TABLE IF EXISTS temp";
             PreparedStatement drop_temp_table = conn.prepareStatement(sql_drop_temp_table);
             drop_temp_table.execute();
 
-            // Creates a temp table used for parity check
             String sql_create_temp_table = "CREATE TABLE temp (org_number VARCHAR(100) PRIMARY KEY)";
             PreparedStatement temp_create = conn.prepareStatement(sql_create_temp_table);
             temp_create.execute();
 
-            // Inserts org_number into the temp table
             String sql_update_temp_table = "INSERT INTO temp (org_number) VALUES (?)";
             PreparedStatement temp_update = conn.prepareStatement(sql_update_temp_table);
             for (APICharityData charity : charities) {
@@ -96,8 +139,7 @@ INSERT INTO charities (org_number, name, status, url, is_pre_approved)
             }
             temp_update.executeBatch();
 
-            // Removes records from main charities table, that don't exist in the temp table.
-             // This makes it so if any organization is removed by IK, it will also be removed from the database.
+            // Removes records not found in the list from charities table
             String sql_delete_old_records = """
                     DELETE FROM charities c
                     WHERE NOT EXISTS (
@@ -118,7 +160,6 @@ WHERE NOT EXISTS (
 
 
         } catch (SQLException e) {
-            // prints whole sql error message
             e.printStackTrace();
             throw new RuntimeException("ERROR: Something went wrong during updating charities table.");
         }