implemented loading banking system from file

res/BankCSV_etwurf.csv

@@ -0,0 +1,6 @@
+Bank;BLZ;Kontonummer;PIN;Kontostand;Kontoart;Zins %;Ueberziehungsbetrag;Kundennummer;Name;Vorname;Kunde Straße;Kunde PLZ;Kunde Ort
+VR Bank Rhein-Neckar;MA2424;4711;1234;50,14 €;Sparkonto;3%;;123456;Mustermann;Max;Bahnhofstraße 1;68159;Mannheim
+VR Bank Rhein-Neckar;MA2424;8321;1234;500,14;Girokonto;;1.000,27 €;123456;Mustermann;Max;Bahnhofstraße 1;68159;Mannheim
+Berliner Bank;19087;1717;1234;500,14;Sparkonto;1,003;;717171;Mustermann;Max;Bahnhofstraße 1;68159;Mannheim
+Berliner Bank;19087;1919;1234;540,2;Sparkonto;1,1;;717171;Mustermann;Max;Bahnhofstraße 1;68159;Mannheim
+Zocker Bank;Zock7777;4444;7777;-8000,5;Girokonto;;50000,5;31124;Hogo;Gruber;Berlinestraß 33 / 1;7899;Berlin

src/me/teridax/jcash/banking/Account.java

@@ -1,5 +1,7 @@
 package me.teridax.jcash.banking;
 
+import me.teridax.jcash.decode.Decoder;
+
 import java.util.Objects;
 
 @SuppressWarnings("unused")
@@ -9,10 +11,33 @@ public abstract class Account {
     private final int pin;
     private final double balance;
 
-    public Account(int iban, int pin) {
+    public Account(int iban, int pin, double balance) {
         this.iban = iban;
         this.pin = pin;
-        this.balance = 0.0d;
+        this.balance = balance;
+    }
+
+    public static Account fromColumns(String[] columns) {
+        Objects.requireNonNull(columns);
+
+        var iban = Decoder.decodeUniqueIdentificationNumber(columns[0]);
+        var pin = Decoder.decodeUniqueIdentificationNumber(columns[1]);
+        var balance = Decoder.decodeCurrency(columns[2]);
+        var type = Decoder.decodeName(columns[3]);
+
+        try {
+            if (type.equals("Sparkonto")) {
+                var interest = Decoder.decodePercent(columns[4]);
+                return new SavingsAccount(iban, pin, balance, interest);
+            } else if (type.equals("Girokonto")) {
+                var overdraft = Decoder.decodeCurrency(columns[5]);
+                return new Girokonto(iban, pin, balance, overdraft);
+            } else {
+                throw new IllegalArgumentException("Invalid account type: " + type);
+            }
+        } catch (IllegalArgumentException | NullPointerException e) {
+            throw new IllegalArgumentException("Account format: ", e);
+        }
     }
 
     public int getIban() {

src/me/teridax/jcash/banking/Bank.java

@@ -8,7 +8,7 @@ public final class Bank {
     private final String blz;
     private final Map<Owner, Set<Account>> accounts;
 
-    private Bank(String blz, String name) {
+    Bank(String blz, String name) {
         this.blz = blz;
         this.name = name;
         this.accounts = new HashMap<>();
@@ -22,6 +22,12 @@ public final class Bank {
         return name;
     }
 
+    public void addAccount(Owner owner, Account account) {
+        var set = this.accounts.getOrDefault(owner, new HashSet<>());
+        set.add(account);
+        this.accounts.put(owner, set);
+    }
+
     @Override
     public boolean equals(Object obj) {
         if (obj instanceof Bank) {
@@ -39,7 +45,7 @@ public final class Bank {
         return accounts.get(owner).toArray(Account[]::new);
     }
 
-    private static String validateBlz(String maybeBlz) {
+    public static String validateBlz(String maybeBlz) {
         var builder = new StringBuilder();
         maybeBlz.trim().chars().filter(ch -> Character.isDigit(ch) || Character.isLetter(ch)).forEach(builder::append);
         var blz = builder.toString();

src/me/teridax/jcash/banking/BankingManagementSystem.java

@@ -1,12 +1,11 @@
 package me.teridax.jcash.banking;
 
-import java.io.File;
+import me.teridax.jcash.decode.Decoder;
+
 import java.io.IOException;
 import java.nio.file.Files;
-import java.util.ArrayList;
+import java.nio.file.Path;
-import java.util.HashSet;
+import java.util.*;
-import java.util.List;
-import java.util.Set;
 
 public final class BankingManagementSystem {
 
@@ -16,22 +15,43 @@ public final class BankingManagementSystem {
         this.banks = new HashSet<>();
     }
 
-    public static BankingManagementSystem loadFromCsv(File file) {
+    private static String[] tail(String[] array, int index) {
+        return Arrays.stream(array).skip(index).toArray(String[]::new);
+    }
 
+    public static BankingManagementSystem loadFromCsv(Path file) {
         try {
-            var content = Files.readString(file.toPath());
+            var bms = new BankingManagementSystem();
+            var content = Files.readString(file);
 
-            var banks = new ArrayList<Bank>();
+            content.lines().skip(1).forEach(line -> {
+                var columns = line.split(";");
 
-            content.lines().forEach(line -> {
+                if (columns.length != 14)
-                // load bank and account from line.
+                    throw new IllegalArgumentException("invalid column count: " + columns.length);
-                // transfer accounts to existing bank if already created
+
+                var owner = Owner.fromColumns(tail(columns, 8));
+                var account = Account.fromColumns(tail(columns, 2));
+
+                var blz = Bank.validateBlz(columns[1]);
+                var name = Decoder.decodeName(columns[0]);
+                var bankOfLine = new Bank(blz, name);
+
+                var bankOfSet = bms.banks.stream().filter(b -> b.equals(bankOfLine)).findFirst();
+                if (bankOfSet.isPresent()) {
+                    bankOfSet.get().addAccount(owner, account);
+                } else {
+                    bankOfLine.addAccount(owner, account);
+                    bms.banks.add(bankOfLine);
+                }
             });
 
-        } catch (IOException e) {
+            return bms;
-            throw new IllegalArgumentException("Could not read file " + file);
-        }
 
-        return null;
+        } catch (IOException e) {
+            throw new IllegalArgumentException("Could not read file " + file, e);
+        } catch (IllegalArgumentException | NullPointerException e) {
+            throw new IllegalArgumentException("Could not parse file " + file, e);
+        }
     }
 }

src/me/teridax/jcash/banking/Girokonto.java

@@ -4,8 +4,8 @@ public class Girokonto extends Account {
 
     private final double overdraft;
 
-    public Girokonto(int iban, int pin, double overdraft) {
+    public Girokonto(int iban, int pin, double balance, double overdraft) {
-        super(iban, pin);
+        super(iban, pin, balance);
         this.overdraft = overdraft;
     }
 

src/me/teridax/jcash/banking/Owner.java

@@ -1,5 +1,7 @@
 package me.teridax.jcash.banking;
 
+import me.teridax.jcash.decode.Decoder;
+
 import java.util.Objects;
 
 @SuppressWarnings("unused")
@@ -11,9 +13,7 @@ public final class Owner {
     private int zip;
     private String city;
 
-    private Owner() { }
+    private Owner(int uid, String familyName, String name, int zip, String city, String street) {
-
-    public Owner(int uid, String familyName, String name, int zip, String city, String street) {
         this.uid = uid;
         this.familyName = familyName;
         this.name = name;
@@ -22,6 +22,22 @@ public final class Owner {
         this.street = street;
     }
 
+    public static Owner fromColumns(String... columns) throws IllegalArgumentException, NullPointerException {
+        Objects.requireNonNull(columns);
+
+        if (columns.length != 6)
+            throw new IllegalArgumentException("Invalid number of columns: " + columns.length);
+
+        var uid = Decoder.decodeUniqueIdentificationNumber(columns[0]);
+        var familyName = Decoder.decodeName(columns[1]);
+        var name = Decoder.decodeName(columns[2]);
+        var street = Decoder.decodeStreet(columns[3]);
+        var zip = Decoder.decodeUniqueIdentificationNumber(columns[4]);
+        var city = Decoder.decodeName(columns[5]);
+
+        return new Owner(uid, familyName, name, zip, city, street);
+    }
+
     public long getUid() {
         return uid;
     }

src/me/teridax/jcash/banking/SavingsAccount.java

@@ -5,8 +5,8 @@ public class SavingsAccount extends Account {
 
     private final double interest;
 
-    public SavingsAccount(int iban, int pin, double interest) {
+    public SavingsAccount(int iban, int pin, double balance, double interest) {
-        super(iban, pin);
+        super(iban, pin, balance);
         this.interest = interest;
     }
 

src/me/teridax/jcash/banking/Testing.java

@@ -0,0 +1,13 @@
+package me.teridax.jcash.banking;
+
+import org.junit.Test;
+
+import java.nio.file.Paths;
+
+public class Testing {
+
+    @Test
+    public void test() {
+        BankingManagementSystem.loadFromCsv(Paths.get("res/BankCSV_etwurf.csv"));
+    }
+}

src/me/teridax/jcash/decode/Decoder.java

@@ -38,7 +38,7 @@ public class Decoder {
         }
     }
 
-    public static int decodeSerialNumber(String number) throws IllegalArgumentException, NullPointerException {
+    public static int decodeUniqueIdentificationNumber(String number) throws IllegalArgumentException, NullPointerException {
         Objects.requireNonNull(number);
 
         // check if the string is a valid unsigned number
@@ -57,11 +57,13 @@ public class Decoder {
 
         var trimmed = name.trim();
 
-        // check if the string is a valid unsigned number
+        var pattern = Pattern.compile("[\\w-\\s]+", Pattern.CASE_INSENSITIVE);
-        if (!trimmed.trim().chars().allMatch(Character::isLetter))
+        var matcher = pattern.matcher(trimmed);
-            throw new IllegalArgumentException("Not a valid name: " + name);
+        if (matcher.find()) {
-
+            return matcher.group();
-        return trimmed;
+        } else {
+            throw new IllegalArgumentException("not a void name");
+        }
     }
 
     public static String decodeStreet(String street) throws IllegalArgumentException, NullPointerException {
@@ -78,9 +80,9 @@ public class Decoder {
 
     @Test
     public void testDecodeSuccessfulFunctions() {
-        decodeSerialNumber("95786978625347895");
+        decodeUniqueIdentificationNumber("95786978625347895");
-        decodeSerialNumber("    927856347   ");
+        decodeUniqueIdentificationNumber("    927856347   ");
-        decodeSerialNumber("0");
+        decodeUniqueIdentificationNumber("0");
 
         decodeName("Adolf");
         decodeName("Günther");
@@ -101,10 +103,10 @@ public class Decoder {
 
     @Test(expected = IllegalArgumentException.class)
     public void testDecodeInvalidFunctions() {
-        decodeSerialNumber("q0948tvb6q047t 740   t74z0tz    784");
+        decodeUniqueIdentificationNumber("q0948tvb6q047t 740   t74z0tz    784");
-        decodeSerialNumber("-39867.8475");
+        decodeUniqueIdentificationNumber("-39867.8475");
-        decodeSerialNumber("-398678475");
+        decodeUniqueIdentificationNumber("-398678475");
-        decodeSerialNumber(" ß9qu908t76q34798t6q734vb9843");
+        decodeUniqueIdentificationNumber(" ß9qu908t76q34798t6q734vb9843");
 
         decodeName("John Doe");
         decodeName("3490qt67v 0b34");