item002 description started

effectivejava/item002/README.md

@@ -1,5 +1,29 @@
 # About this kata
 
+This kata refers to the book Effective Java by Joshua Bloch.
+It addresses
+
+Item 2: Consider a builder when faced with many constructor parameters.
+
 # Problem description
+telescoping constructor pattern ???
+-> In Java, there is no support for default values for constructor parameters. As a workaround, a technique called "Telescoping constructor" is often used. A class has multiple constructors, where each constructor calls a more specific constructor in the hierarchy, which has more parameters than itself, providing default values for the extra parameters. The next constructor does the same until there is no left.
+
+public Person(String firstName, String lastName) {
+        this(firstName, lastName, "No description available");
+    }
+
+    public Person(String firstName, String lastName, String description) {
+        this(firstName, lastName, description, -1);
+    }
+
+    public Person(String firstName, String lastName, String description, int age) {
+        this.firstName = firstName;
+        this.lastName = lastName;
+        this.description = description;
+        this.age = age;
+    }
+
+JavaBeans pattern precludes the possibility of making a class immuteable (->Item 17!)
 
 # Clues