Updated missing methods in Exchange class

src/main/java/Exchange.java

@@ -41,25 +41,53 @@ public Stock getStock(String symbol) {
     }
 
     public List<Stock> findStocks(String searchTerm) {
-            List<Stock> result = new ArrayList<>();
+        List<Stock> result = new ArrayList<>();
+        String lowerSearch = searchTerm.toLowerCase();
 
         for (Stock stock : stockMap.values()) {
-            if (stock.getSymbol().contains(searchTerm)
-                    || stock.getCompany().contains(searchTerm)) {
+            if (stock.getSymbol().toLowerCase().contains(lowerSearch)
+                    || stock.getCompany().toLowerCase().contains(lowerSearch)) {
                 result.add(stock);
             }
         }
 
         return result;
         }
 
-    // public Transaction buy(String symbol, BigDecimal quantity, Player player) {
-    //     return;
-    // }
+    public Transaction buy(String symbol, BigDecimal quantity, Player player) {
+        Stock stock = getStock(symbol);
+
+         // unngå nullpointerexception
+        if (stock == null) {
+            return null; 
+        }
+
+        // lager en ny "andel" basert på nåværende salgspris
+        Share shareToBuy = new Share(stock, quantity, stock.getSalesPrice());
+
+        // oppretter kjøpstransaksjonen for den uka
+        Purchase purchase = new Purchase(shareToBuy, this.week);
+
+        // committer til player
+        purchase.commit(player);
+
+        return purchase;
+    }
+
+    public Transaction sell(Share share, Player player) {
+        // unngå nullpointerexception
+        if (share == null) {
+            return null;
+        }
 
-    // public Transaction sell(Share share, Player player) {
-    //     return;
-    // }
+        // oppretter salgstransaksjonen for den uka
+        Sale sale = new Sale(share, this.week);
+
+        // commiter til player
+        sale.commit(player);
+
+        return sale;
+    }
 
     public void advance() {
 

src/main/java/Player.java

@@ -24,11 +24,11 @@ public BigDecimal getMoney() {
     }
 
     public void addMoney(BigDecimal amount) {
-        this.money.add(amount);
+        this.money = this.money.add(amount);
     }
 
     public void withdrawMoney(BigDecimal amount) {
-        this.money.subtract(amount);
+        this.money = this.money.subtract(amount);
     }
 
     public Portfolio getPortfolio() {