Convert all PreparedStatement to regular Statements

PreparedStatement are not that useful for our use case, but add a lot of complexity

src/main/java/fr/insa/clavardator/db/DatabaseController.java

@@ -89,8 +89,8 @@ public class DatabaseController {
 		executeUpdate("CREATE TABLE IF NOT EXISTS message " +
 				"(id            INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL," +
 				" timestamp     DATETIME                          NOT NULL, " +
-				" sender        INTEGER                           NOT NULL, " +
-				" recipient     INTEGER                           NOT NULL, " +
+				" sender        INTEGER UNSIGNED                  NOT NULL, " +
+				" recipient     INTEGER UNSIGNED                  NOT NULL, " +
 				" text          TEXT, " +
 				" file_path     TEXT)");
 	}
@@ -102,8 +102,8 @@ public class DatabaseController {
 	private void createUserTable() throws SQLException {
 		Log.v(getClass().getSimpleName(), "Creating table user...");
 		executeUpdate("CREATE TABLE IF NOT EXISTS user " +
-				"(id            INTEGER PRIMARY KEY NOT NULL," +
-				" username      INTEGER             NOT NULL)");
+				"(id            INTEGER UNSIGNED PRIMARY KEY NOT NULL," +
+				" username      TINYTEXT                     NOT NULL)");
 	}
 
 	/**
@@ -198,30 +198,31 @@ public class DatabaseController {
 	 */
 	public void addMessage(Message message, MessageCallback callback) {
 		try {
-			// Insert the new message
-			final String insertMessageSql =
-					"INSERT INTO message " +
-							"(timestamp, sender, recipient, text, file_path) " +
-							"VALUES (?, ?, ?, ?, ?)";
-			PreparedStatement insertMsgStmt = connection.prepareStatement(insertMessageSql);
-			insertMsgStmt.setTimestamp(1, new Timestamp(message.getDate().getTime()));
-			insertMsgStmt.setInt(2, message.getSender().id);
-			insertMsgStmt.setInt(3, message.getRecipient().id);
-			insertMsgStmt.setString(4, message.getText());
-			if (insertMsgStmt instanceof FileMessage) {
-				// TODO: store file in file system
+			// TODO: Handle messages containing files:
+			//       store file in file system and put the path in filePath
+			String filePath = "NULL";
+			if (message instanceof FileMessage) {
 				Log.w(getClass().getSimpleName(), "Functionality not implemented: file has not been saved");
-				//			stmt.setString(5, ((FileMessage) stmt).getFileName());
-			} else {
-				insertMsgStmt.setString(5, null);
+//				filePath = ((FileMessage) message).getFileName();
 			}
-			Log.v(getClass().getSimpleName(), "Inserting message into db... ");
-			int rowsModified = insertMsgStmt.executeUpdate();
-			Log.v(getClass().getSimpleName(), rowsModified + " rows modified");
-			insertMsgStmt.close();
 
+			// Insert the new message
+			Log.v(getClass().getSimpleName(), "Inserting message into db... ");
+			executeUpdate("INSERT INTO message " +
+					"(timestamp, sender, recipient, text, file_path) " +
+					"VALUES (" +
+					message.getDate().getTime() + ", " +
+					message.getSender().id + ", " +
+					message.getRecipient().id + ", " +
+					"\"" + message.getText() + "\", " +
+					filePath +
+					")");
+
+			// Insert the sender
 			Log.v(getClass().getSimpleName(), "Inserting sender into db... ");
 			addUser(message.getSender());
+
+			// Insert the recipient
 			Log.v(getClass().getSimpleName(), "Inserting recipient into db... ");
 			addUser(message.getRecipient());
 
@@ -240,17 +241,9 @@ public class DatabaseController {
 	 * @throws SQLException SQL error
 	 */
 	private void addUser(UserInformation user) throws SQLException {
-		final String insertUserSql =
-				"INSERT OR IGNORE INTO user " +
-						"(id, username) " +
-						"VALUES (?, ?)";
-		PreparedStatement statement = connection.prepareStatement(insertUserSql);
-		// Add sender
-		statement.setInt(1, user.id);
-		statement.setString(2, user.getUsername());
-		final int rowsModified = statement.executeUpdate();
-		Log.v(getClass().getSimpleName(), rowsModified + " rows modified");
-		statement.close();
+		executeUpdate("INSERT OR IGNORE INTO user " +
+				"(id, username) " +
+				"VALUES (" + user.id + ", \"" + user.getUsername() + "\")");
 	}
 
 	/**