From f20d786191ed5fba1829d29aebfec45cdf990e7c Mon Sep 17 00:00:00 2001
From: Marcus Adrian <marcus.adrian75@gmail.com>
Date: Fri, 7 Aug 2020 22:10:40 +0200
Subject: [PATCH] self() in parent is sufficient

---
 .../chapter2/item2/hierarchicalbuilder/Calzone.java      | 2 --
 .../chapter2/item2/hierarchicalbuilder/NyPizza.java      | 1 -
 .../chapter2/item2/hierarchicalbuilder/Pizza.java        | 9 +++++++--
 3 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/src/effectivejava/chapter2/item2/hierarchicalbuilder/Calzone.java b/src/effectivejava/chapter2/item2/hierarchicalbuilder/Calzone.java
index b26ab600..d622c1c8 100644
--- a/src/effectivejava/chapter2/item2/hierarchicalbuilder/Calzone.java
+++ b/src/effectivejava/chapter2/item2/hierarchicalbuilder/Calzone.java
@@ -15,8 +15,6 @@ public Builder sauceInside() {
         @Override public Calzone build() {
             return new Calzone(this);
         }
-
-        @Override protected Builder self() { return this; }
     }
 
     private Calzone(Builder builder) {
diff --git a/src/effectivejava/chapter2/item2/hierarchicalbuilder/NyPizza.java b/src/effectivejava/chapter2/item2/hierarchicalbuilder/NyPizza.java
index 3e8c04f8..ab02117f 100644
--- a/src/effectivejava/chapter2/item2/hierarchicalbuilder/NyPizza.java
+++ b/src/effectivejava/chapter2/item2/hierarchicalbuilder/NyPizza.java
@@ -18,7 +18,6 @@ public Builder(Size size) {
             return new NyPizza(this);
         }
 
-        @Override protected Builder self() { return this; }
     }
 
     private NyPizza(Builder builder) {
diff --git a/src/effectivejava/chapter2/item2/hierarchicalbuilder/Pizza.java b/src/effectivejava/chapter2/item2/hierarchicalbuilder/Pizza.java
index 77925cda..910e6ee2 100644
--- a/src/effectivejava/chapter2/item2/hierarchicalbuilder/Pizza.java
+++ b/src/effectivejava/chapter2/item2/hierarchicalbuilder/Pizza.java
@@ -18,8 +18,13 @@ public T addTopping(Topping topping) {
 
         abstract Pizza build();
 
-        // Subclasses must override this method to return "this"
-        protected abstract T self();
+        @SuppressWarnings("unchecked")
+        protected T self() {
+            // this is always of type T
+            // so there is no need to override
+            // self in subclasses
+            return (T) this;
+        }
     }
     
     Pizza(Builder<?> builder) {