add: env file for secret credential configuration

.gitignore

@@ -35,4 +35,6 @@ build/
 .vscode/
 
 ### Mac OS ###
-.DS_Store
+.DS_Store
+
+.env

src/main/java/andromeda/hebat/finalisjtiadmin/core/Database.java

@@ -2,18 +2,24 @@
 
 import java.sql.*;
 
+import andromeda.hebat.finalisjtiadmin.helper.EnvLoader;
+
 public class Database {
 
-    private static final String SERVER_NAME = "MSI";
-    private static final String DB_NAME = "db_temp_finalis_jti";
-    private static final String USER = "sa";
-    private static final String PASSWORD = "12345";
+    static {
+        EnvLoader.loadEnv(".env");
+    }
+
+    private static final String DB_SERVER = System.getProperty("DB_SERVER");
+    private static final String DB_NAME = System.getProperty("DB_NAME");
+    private static final String DB_USER = System.getProperty("DB_USER");
+    private static final String DB_PASSWORD = System.getProperty("DB_PASSWORD");
 
     public static Connection getConnection() {
-        final String URL = "jdbc:sqlserver://"+SERVER_NAME+";Database="+DB_NAME+";encrypt=false";
+        final String URL = "jdbc:sqlserver://"+DB_SERVER+";Database="+DB_NAME+";encrypt=false";
 
         try {
-            return DriverManager.getConnection(URL, USER, PASSWORD);
+            return DriverManager.getConnection(URL, DB_USER, DB_PASSWORD);
         } catch (SQLException e) {
             e.printStackTrace();
         }

src/main/java/andromeda/hebat/finalisjtiadmin/helper/EnvLoader.java

@@ -0,0 +1,36 @@
+package andromeda.hebat.finalisjtiadmin.helper;
+
+import java.io.BufferedReader;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+
+public class EnvLoader {
+    public static void loadEnv(String filePath) {
+        Map<String, String> envMap = new HashMap<>();
+
+        try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                line = line.trim();
+                if (line.isEmpty() || line.startsWith("#")) {
+                    continue;
+                }
+
+                String[] parts = line.split("=", 2);
+                if (parts.length == 2) {
+                    String key = parts[0].trim();
+                    String value = parts[1].trim();
+                    envMap.put(key, value);
+                }
+            }
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+
+        for (Map.Entry<String, String> entry : envMap.entrySet()) {
+            System.setProperty(entry.getKey(), entry.getValue());
+        }
+    }
+}