Added ExchangeTest class

target/test-classes/ExchangeTest.java

@@ -0,0 +1,50 @@
+import static org.junit.Assert.assertEquals;
+
+import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.junit.Before;
+import org.junit.Test;
+
+public class ExchangeTest {
+
+    private Exchange exchange;
+    private Stock apple;
+    private Stock google;
+
+    @Before
+    public void setUp() {
+        apple = new Stock("AAPL", "Apple", new BigDecimal("100"));
+        google = new Stock("GOOGL", "Google", new BigDecimal("200"));
+
+        List<Stock> stocks = new ArrayList<>();
+        stocks.add(apple);
+        stocks.add(google);
+
+        exchange = new Exchange("ABC", stocks);
+    }
+
+    @Test
+    public void testFindStocksBySymbol() {
+        List<Stock> result = exchange.findStocks("AAPL");
+
+        assertEquals(1, result.size());
+        assertEquals("AAPL", result.get(0).getSymbol());
+    }
+
+    @Test
+    public void testFindStocksByCompanyNames() {
+        List<Stock> result = exchange.findStocks("e");
+
+        assertEquals(2, result.size());
+    }
+
+    @Test
+    public void testFindStocksNotInList() {
+        List<Stock> result = exchange.findStocks("Samsung");
+
+        assertEquals(0, result.size());
+    }
+
+}