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effectivejava/item001/README.md

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+# About this kata
+This kata refers to the book Effective Java by Joshua Bloch.
+It addresses
+
+Item 1: Consider static factory methods instead of constructors.
+
+# Problem description
+Provid a class that 
+Use factory method to construct an instance by a good understandable name.
+The instance shall be only created when there is no existing one.
+
+advantages of factory method usage instead of constructors:
+# Unlike constructors the method has a meaningful name.
+# Unlike constructors it is not required to create a new object each time they are invoked.
+# Unlike constructors it can return an object of any subtype of their return type.
+# The returned object can vary from call to call as function of the input parameters.
+# The class of the returned object need not exist when the class containing the method is written. ????
+
+
+# Clues