major refactoring: working towards more interface-implementation splitting

core/src/main/java/de/srsoftware/umbrella/core/BaseHandler.java

@@ -5,6 +5,7 @@ import static de.srsoftware.tools.Optionals.nullable;
 import static java.lang.System.Logger.Level.DEBUG;
 import static java.lang.System.Logger.Level.WARNING;
 import static java.net.HttpURLConnection.*;
+import static java.text.MessageFormat.format;
 
 import com.sun.net.httpserver.HttpExchange;
 import de.srsoftware.tools.Path;
@@ -73,4 +74,8 @@ public abstract class BaseHandler extends PathHandler {
 	public boolean unauthorized(HttpExchange ex) throws IOException {
 		return sendEmptyResponse(HTTP_FORBIDDEN,ex);
 	}
+
+	public boolean notImplemented(HttpExchange ex,String message,Object clazz) throws IOException{
+		return sendContent(ex,HTTP_NOT_IMPLEMENTED,format(message,clazz.getClass().getSimpleName()));
+	}
 }

core/src/main/java/de/srsoftware/umbrella/core/ConnectionProvider.java

@@ -7,12 +7,17 @@ import java.sql.SQLException;
 import java.util.HashMap;
 import org.sqlite.SQLiteDataSource;
 
-public class ConnectionProvider extends HashMap<File, Connection> {
-	public Connection get(Object o) {
+public class ConnectionProvider {
+
+	private static final HashMap<File, Connection> connections = new HashMap<>();
+
+	private ConnectionProvider(){}
+
+	public static Connection connect(Object o) {
 		if (o instanceof String filename) o = new File(filename);
 		if (o instanceof File dbFile) try {
-			var conn = super.get(dbFile);
-			if (conn == null) put(dbFile, conn = open(dbFile));
+			var conn = connections.get(dbFile);
+			if (conn == null) connections.put(dbFile, conn = open(dbFile));
 			return conn;
 		} catch (SQLException sqle) {
 			throw new RuntimeException(sqle);
@@ -20,7 +25,7 @@ public class ConnectionProvider extends HashMap<File, Connection> {
 		return null;
 	}
 
-	private Connection open(File dbFile) throws SQLException {
+	private static Connection open(File dbFile) throws SQLException {
 		SQLiteDataSource dataSource = new SQLiteDataSource();
 		dataSource.setUrl("jdbc:sqlite:%s".formatted(dbFile));
 		return dataSource.getConnection();

core/src/main/java/de/srsoftware/umbrella/core/UmbrellaException.java

@@ -1,19 +1,20 @@
 /* © SRSoftware 2025 */
 package de.srsoftware.umbrella.core;
 
+import static de.srsoftware.umbrella.core.ResponseCode.HTTP_SERVER_ERROR;
 import static java.text.MessageFormat.format;
 
 
 public class UmbrellaException extends Exception{
 	private final int statusCode;
 
-	public UmbrellaException(int statusCode, String message){
-		super(message);
-		this.statusCode = statusCode;
+	public UmbrellaException(String message, Object ... fills){
+		this(HTTP_SERVER_ERROR,message,fills);
 	}
 
 	public UmbrellaException(int statusCode, String message, Object ... fills){
-		this(statusCode,format(message,fills));
+		super(format(message,fills));
+		this.statusCode = statusCode;
 	}
 
 	public UmbrellaException causedBy(Exception e) {

core/src/main/java/de/srsoftware/umbrella/core/api/CompanyService.java

@@ -0,0 +1,9 @@
+/* © SRSoftware 2025 */
+package de.srsoftware.umbrella.core.api;
+
+import de.srsoftware.umbrella.core.model.UmbrellaUser;
+import java.util.List;
+
+public interface CompanyService {
+	public List<UmbrellaUser> getMembers(long companyId);
+}

core/src/main/java/de/srsoftware/umbrella/core/api/UserService.java

@@ -2,12 +2,13 @@
 package de.srsoftware.umbrella.core.api;
 
 import com.sun.net.httpserver.HttpExchange;
-import de.srsoftware.umbrella.core.Token;
 import de.srsoftware.umbrella.core.UmbrellaException;
+import de.srsoftware.umbrella.core.model.Token;
 import de.srsoftware.umbrella.core.model.UmbrellaUser;
 import java.util.Optional;
 
-public interface UserHelper {
+public interface UserService {
+	UmbrellaUser loadUser(long userId) throws UmbrellaException;
 	Optional<UmbrellaUser> loadUser(Optional<Token> sessionToken) throws UmbrellaException;
 	Optional<UmbrellaUser> loadUser(HttpExchange ex) throws UmbrellaException;
 }

core/src/main/java/de/srsoftware/umbrella/core/model/Session.java

@@ -0,0 +1,16 @@
+/* © SRSoftware 2025 */
+package de.srsoftware.umbrella.core.model;
+
+import de.srsoftware.tools.SessionToken;
+import java.time.Instant;
+
+/* © SRSoftware 2025 */
+public record Session(UmbrellaUser user, Token token, Instant expiration) {
+	public Session extended(Instant newExpiration) {
+		return new Session(user,token,newExpiration);
+	}
+
+	public SessionToken cookie() {
+		return new SessionToken(token.toString(),"/",expiration,true);
+	}
+}

core/src/main/java/de/srsoftware/umbrella/core/model/Token.java

@@ -1,9 +1,10 @@
 /* © SRSoftware 2025 */
-package de.srsoftware.umbrella.core;
+package de.srsoftware.umbrella.core.model;
 
 import static de.srsoftware.umbrella.core.Constants.TOKEN;
 
 import de.srsoftware.tools.SessionToken;
+import de.srsoftware.umbrella.core.AddableMap;
 import java.util.UUID;
 
 public class Token implements CharSequence{