Fix for String equals check

persistence-modules/java-jpa-3/src/main/java/com/baeldung/jpa/equality/EqualByBusinessKey.java

@@ -44,7 +44,7 @@ public class EqualByBusinessKey {
             return false;
         }
         if (obj instanceof EqualByBusinessKey) {
-            if (((EqualByBusinessKey) obj).getEmail() == getEmail()) {
+            if (((EqualByBusinessKey) obj).getEmail().equals(getEmail())) {
                 return true;
             }
         }