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--- principles:murphy_s_law [2020-10-12 14:36] – old revision restored (2013-01-16 15:38) 159.69.186.191
+++ principles:murphy_s_law [2020-10-12 20:32] – old revision restored (2013-01-16 13:53) 159.69.186.191
@@ Line 146: / Line 146: @@
 Note that the typecast is rather a symptom than the actual problem here. The problem is, that the ''List'' interface is not generic and the symptom is the typecast. The reason for this flaw is, that the ''List'' interface predates the introduction of generics in Java.
-==== Example 3: Date, Mutability/Aliasing ====
-In Java the classes [[http://docs.oracle.com/javase/7/docs/api/java/util/Date.html|''Date'']] as well as the newer [[http://docs.oracle.com/javase/7/docs/api/java/util/Calendar.html|''Calendar'']] are mutable which means the reference semantics of Java objects may cause unintended alternations of date values. Eventually someone will copy the reference to a date object instead of copying the object itself, which is usually a mistake when programming with dates.
-<code java>
-Date date1 = new Date(2013, 01, 16);
-Date date2 = date1;
-System.out.println(date1); // Sun Feb 16 00:00:00 CET 3913
-System.out.println(date2); // Sun Feb 16 00:00:00 CET 3913
-date1.setMonth(2);
-System.out.println(date1); // Sun Mar 16 00:00:00 CET 3913
-System.out.println(date2); // Sun Mar 16 00:00:00 CET 3913
-</code>
-Furthermore as can be seen in the code above, the month value counterintuitively is zero-based, which results in 1 meaning February. This obviously is another source for mistakes.
-Because of these and several other flaws in the design of the Java date API, most of the methods in ''Date'' are deprecated and also the newer ''Calendar'' API will be replaced by a [[http://openjdk.java.net/jeps/150|new API]] in Java 8.
 ===== Description Status =====