implemented listing of list members

src/main/java/de/srsoftware/widerhall/data/User.java

@@ -8,10 +8,7 @@ import java.security.InvalidKeyException;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.time.LocalDate;
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
+import java.util.*;
 
 import static de.srsoftware.widerhall.data.Database.*;
 import static de.srsoftware.widerhall.Constants.*;
@@ -50,6 +47,22 @@ public class User {
         Database.open().query(sql.toString()).run();
     }
 
+    public static List<User> loadAll(Collection<String> emails) throws SQLException {
+        var rs = Database.open()
+                .query("SELECT * FROM "+TABLE_NAME)
+                .where(EMAIL,emails)
+                .exec();
+        var list = new ArrayList<User>();
+        while (rs.next()){
+            var email = rs.getString(EMAIL);
+            var name = rs.getString(NAME);
+            var salt = rs.getString(SALT);
+            var hashedPass = rs.getString(HASHED_PASS);
+            list.add(new User(email,name,salt,hashedPass));
+        }
+        return list;
+    }
+
     public String email() {
         return email;
     }