Multi Currency Money [springframeworkguru#19. Dollar side effects, equality for All]

Author: gechulim

src/test/java/guru/springframework/Dollar.java

@@ -9,4 +9,10 @@ public Dollar(int amount) {
     Dollar times(int multiplier) {
         return new Dollar(this.amount * multiplier);
     }
+
+    @Override
+    public boolean equals(Object o) {
+        Dollar dollar = (Dollar) o;
+        return amount == dollar.amount;
+    }
 }

src/test/java/guru/springframework/MoneyTest.java

@@ -3,6 +3,7 @@
 import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
 
 public class MoneyTest {
     @Test
@@ -14,4 +15,9 @@ void testMultiplication() {
         assertEquals(15, product.amount);
     }
 
+    @Test
+    void testEquality() {
+        assertEquals(new Dollar(6), new Dollar(6));
+        assertNotEquals(new Dollar(6), new Dollar(8));
+    }
 }