Head in the Cloud

One thing to remember,  System.DateTime  has no knowledge of timezone. It’s only aware that the date and time represents UTC or the local timezone of the machine on which the code is running. In the cloud, by default (and it’s best to keep it that way), the “server’s” timezone is set to UTC. So what? Well… The serializers do some magic that can yield undesired results depending on your situation. Take the following… DateTime today = DateTime . Today ; Seems harmless. If you inspect this instance further, you’ll see that the Kind is set to  DateTimeKind.Local . So, when working with the instance, it will behave in the timezone of the machine. If you serialize it on your laptop, and your laptop’s timezone is set to “Easter Standard Time” (America/New York for you Linux/Mac folks)… string json = JsonConvert . SerializeObject ( today ); Console . WriteLine ( json ); …you get… 2018-02-23T00:00:00-05:00 Notice the timezone offset. If  Dat...

Working with dates in Java (though not limited to Java) has always been a nightmare. There are lots of good articles out there in Google Land on the topic, but after some very good questions from my class, I thought I'd add my two-cents and code samples to the mix. Much of the confusion centered around conversion, so here's some basic how-to snippits: Convert java.util.Calendar to java.util.Date: java.util.Calendar calendar = java.util.Calendar.getInstance(); java.util.Date utilDate = calendar.getTime(); //or by using the constructor java.util.Date utilDate = new java.util.Date(calendar.getTimeInMillis()); Convert java.util.Date to java.sql.Date: java.util.Date utilDate = java.util.Calendar.getInstance().getTime(); java.sql.Date sqlDate = new java.sql.Date(utilDate.getTime()); Convert java.util.Calendar to java.sql.Date: java.util.Calendar calendar = java.util.Calendar.getInstance(); java.sql.Date utilDate = new java.sql.Date(calendar.getTimeInMillis()); Here we have to create...