remember login state, and check if user is logged in on page

src/main.java

@@ -1,5 +1,6 @@
 import db.jdcb;
 
+import java.io.IOException;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 
@@ -11,6 +12,17 @@ public class main {
         D.printList();
         */
 
+        Runtime.getRuntime().addShutdownHook(new Thread(() -> {
+            try {
+                Thread.sleep(200);
+                System.out.println("Shutting down ...");
+
+                //shutdown routine
+            }  catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }));
+
         Thread mythread = new Thread(() -> new website.Webserver().startserver());
         mythread.start();
 

src/website/CheckLoginState.java

@@ -0,0 +1,22 @@
+package website;
+
+import java.util.HashMap;
+
+public class CheckLoginState extends PostRequest {
+    @Override
+    public String request(HashMap<String, String> params) {
+        System.out.println("checkin login state");
+        if ((params.get("action")).equals("getloginstate")){
+            if (LoginState.getObject().isLoggedIn()){
+                return "{\"loggedin\":true, \"username\":\""+LoginState.getObject().getUsername()+"\"}";
+            }else {
+                return "{\"loggedin\":false}";
+            }
+        }else if ((params.get("action")).equals("logout")){
+            System.out.println("logging out");
+            LoginState.getObject().logOut();
+            return "{\"loggedin\":false}";
+        }
+        return "{\"loggedin\":false}";
+    }
+}

src/website/LoginRequest.java

@@ -22,6 +22,8 @@ public class LoginRequest extends PostRequest {
                 //success
                 if (HttpTools.StringToMD5(password).equals(s.getString("password"))) {
                     System.out.println("login success");
+                    LoginState.getObject().logIn();
+                    LoginState.getObject().setAccountData(username,"","","");
                     response = "{\"accept\": true}";
                 } else {
                     System.out.println("wrong password");

src/website/LoginState.java

@@ -0,0 +1,53 @@
+package website;
+
+public class LoginState {
+    private LoginState() {}
+
+   private static LoginState mythis=new LoginState();
+
+    public static LoginState getObject(){
+        return mythis;
+    }
+
+    String username;
+    String firstname;
+    String lastname;
+    String email;
+
+    boolean loggedin = false;
+
+    public void logIn(){
+        loggedin=true;
+    }
+
+    public void logOut(){
+        loggedin=false;
+    }
+
+    public void setAccountData(String username, String firstname, String lastname, String email){
+        this.username=username;
+        this.firstname=firstname;
+        this.lastname=lastname;
+        this.email=email;
+    }
+
+    public boolean isLoggedIn(){
+        return loggedin;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public String getFirstname() {
+        return firstname;
+    }
+
+    public String getLastname() {
+        return lastname;
+    }
+
+    public String getEmail() {
+        return email;
+    }
+}

src/website/RegisterRequest.java

@@ -14,7 +14,7 @@ public class RegisterRequest extends PostRequest{
         jdcb myjd = new jdcb("users", "kOpaIJUjkgb9ur6S", "wasteinformation");
         int s = myjd.executeUpdate("INSERT INTO `user` (`username`, `firstName`, `secondName`, `password`, `email`, `logindate`) VALUES ('"+params.get("username")+"', '"+params.get("firstname")+"', '"+params.get("lastname")+"', '"+passhash+"', '"+params.get("email")+"', current_timestamp());");
 
-
+        // TODO: 27.09.19 detect if register process was successful and reply right json
         return "{\"accept\": true}";
     }
 }

src/website/Webserver.java

@@ -19,6 +19,7 @@ public class Webserver {
         server.createContext("/", new MainPage());
         server.createContext("/senddata/loginget", new LoginRequest());
         server.createContext("/senddata/registerpost",new RegisterRequest());
+        server.createContext("/senddata/checkloginstate",new CheckLoginState());
 
         server.setExecutor(null); // creates a default executor
         server.start();