Added Checkstyle to Purchase

src/main/java/Model/Purchase.java

@@ -1,32 +1,36 @@
 package Model;
+
 import java.math.BigDecimal;
 
+/**
+ * Purchase class whenever the player makes a purchase.
+ */
 public class Purchase extends Transaction {
-    public Purchase(Share share, int week) {
-        super(share, week, new PurchaseCalculator(share));  
-    }
+  public Purchase(Share share, int week) {
+    super(share, week, new PurchaseCalculator(share));  
+  }
 
-    @Override
-    public void commit(Player player) {
-        if (player == null) {
-            throw new IllegalArgumentException("Player cannot be null");
-        }
-        if (isCommitted()) {
-            throw new IllegalStateException("Purchase has already been committed");
-        }
+  @Override
+  public void commit(Player player) {
+    if (player == null) {
+      throw new IllegalArgumentException("Player cannot be null");
+    }
+    if (isCommitted()) {
+      throw new IllegalStateException("Purchase has already been committed");
+    }
 
-        BigDecimal price = this.getCalculator().calculateTotal();
+    BigDecimal price = this.getCalculator().calculateTotal();
 
-        if (player.getMoney().compareTo(price) < 0) {
-            throw new IllegalStateException(
-                "Insufficient funds: required " + price + ", available " + player.getMoney()
-            );
-        }
+    if (player.getMoney().compareTo(price) < 0) {
+      throw new IllegalStateException(
+        "Insufficient funds: required " + price + ", available " + player.getMoney()
+      );
+    }
 
-        player.withdrawMoney(price);
-        player.getPortfolio().addShare(this.getShare());
-        player.getTransactionArchive().add(this);
+    player.withdrawMoney(price);
+    player.getPortfolio().addShare(this.getShare());
+    player.getTransactionArchive().add(this);
 
-        this.committed = true;
-    }
+    this.committed = true;
+  }
 }