Add stock attribute

src/BuyTrade.java

 
 public class BuyTrade extends Trade {
-	BuyTrade(int time, Customer c, int qty, float price) {
-		super(time, "BUY", c, qty, price);
+	BuyTrade(int time, Customer c, Stock stock, int qty, float price) {
+		super(time, "BUY", c, stock, qty, price);
 	}
 }

src/SellTrade.java

 public class SellTrade extends Trade {
-	SellTrade(int time, Customer c, int qty, float price) {
-		super(time, "SELL", c, qty, price);
+	SellTrade(int time, Customer c, Stock stock, int qty, float price) {
+		super(time, "SELL", c, stock, qty, price);
 	}
 }

src/Trade.java

@@ -4,13 +4,15 @@ public abstract class Trade {
 	int time;
 	String type;
 	Customer c;
+	Stock stock;
 	
-	Trade(int time, String type, Customer c, int qty, float price) {
+	Trade(int time, String type, Customer c, Stock stock, int qty, float price) {
 		this.qty = qty;
 		this.price = price;
 		this.c = c;
 		this.time = time;
 		this.type = type;
+		this.stock = stock;
 	}
 	
 	int getQty() {	return qty; }
@@ -22,4 +24,6 @@ public abstract class Trade {
 	String getType() { return type; }
 	
 	Customer getCustomer() { return c; }
+	
+	Stock getStock() { return stock; }
 }