Understanding Software Design Patterns

Lately I have been quite busy with work and have not had time to write posts for this blog. Today I woke up shortly after 04:00 AM. Typically I go back to sleep until my alarm goes off, but today I had the desire to get up and so some on-line reading. I found the article Understanding Software Design Patterns by Bryant Son. The article deals with three design patterns:  Singleton, Factory and Observer. Given that I have generated at least one post Singleton Threads using the Singleton pattern, I spent time reading the article and experimenting with it. I will cover the last two patterns in a different post. Continue reading “Understanding Software Design Patterns”

13 to 15 Java Questions

I have noticed that multiple times in a week I wake up and check my phone for the time and it is 04:47 AM. Given that I live in the Twin Cities of Minneapolis and St. Paul, there is some day light at that time. I recall a few years ago when I would get up around 05:00 AM to walk the dogs.

I do have an alarm set for 05:00 AM 7 days a week. In addition I have set an appointment in my Google calendar for the same time. Today after waking up at 04:47 AM I checked the calendar to see if there was a message or notification set for 15 minutes before (04:45 AM). Both notification and email are set for 05:00 AM. Continue reading “13 to 15 Java Questions”

Securing MongoDB

Today is a summer Saturday morning in the Twin Cities of Minneapolis and St. Paul. It is not as bright as usual, it appears to be cloudy but it is relatively early. I woke up around 04:30 AM and decided to get up, read the news for a few minutes, and then decided to write this posts. My motivation is twofold. The first and most important is due to the fact that I am officially starting a new project at work using MongoDB. I will be using a local version of MongoDB which later will be moved to use Atlas on the cloud. The database will contain sensitive patient data. The second is the number of recent posts regarding data leaks on NoSQL bases. This morning I just read “MongoDB Leak Exposed Millions of Medical Insurance Records” which seems to illustrate the fact that people forgets to secure their MongoDB instance. Continue reading “Securing MongoDB”

Prefix Sum Algorithm

UPDATE – This post has been updated.

A lot of good things are happening in my work life. I will continue to comment in future posts.

Today I discussed an idea regarding a new service which will extract data from a huge set of files and will be able to allow access to users. Sorry I will not be able to comment much more on this. I have committed to have a first pass of the architecture and high level design documents first thing Monday morning. Continue reading “Prefix Sum Algorithm”

How to Create a Great Team Culture

This morning I woke up and put my cell phone on the tile ledge surrounding the Jacuzzi tub in the bathroom of my bedroom.  The ledge is 22 inches in height. My Samsung Galaxy 8+ had on an “i-Blason Samsung Galaxy S8+ Plus case, [Ares] Full-Body Rugged Clear Bumper Case with Built-in Screen Protector for Samsung Galaxy S8+ Plus 2017 Release (Black)” cover. It fell and hit the floor. The screen cracked on one corner. Not sure what was the purpose of the protector. I will be replacing my cell phone in the near future with a Google Pixel 3a XL. Continue reading “How to Create a Great Team Culture”

DynamoDB

I do not like to live of past memories but this morning I spent a few minutes updating the About me … section in this blog. I included the fact that since my early 20’s I started dabbling with starting my own businesses. At the time I got together with a couple friends and opened a liquor store. I was able to secure beer distribution of one of the largest breweries in Peru. The rules are that breweries sell only via distributors and distributors only sell to liquor stores. About a year after, I sold the business due to the fact that I received a scholarship to attend Cornell University and permanently move to the USA.

Continue reading “DynamoDB”

Arrays Left Rotation

Last evening I read the article “Programmable Solid-State Storage in Future Cloud Datacenters” by Jaeyound Do, Sudipta Sengupta and Steven Swanson which appeared in volume 62 number 6 edition of Communications of the ACM. This morning I read it once again. As you might already know I am passionate about storage and have been working on it for a while. The article deal with SSD drives and how they can help improve performance by providing compute resources close to the data. Continue reading “Arrays Left Rotation”

Simple Array Sum

It is a sunny but not so warm day in the Twin Cities of Minneapolis and St. Paul. The high for today will be 68 F which is a few degrees below the average high for this time of the year. Looks like a perfect day for a walk. My wife and I will be out and about after work today.

This HackerRank challenge is quite simple. The reason I went for it is due to the fact that a few weeks ago I exchanged some messages with JAVAAID. He has a YouTube channel and solves HackerRank challenges. Continue reading “Simple Array Sum”

11 to 12 Java Questions

As I mentioned in my previous post, my wife and I spent a week in Portugal. On the previous post I covered the days in Salema which is a town in the Algarve area. I will now comment on our stay in Lisbon.

Lisbon continues to grow. We stayed in an area named “Barrios Altos”. The area is hilly, the streets are paved with cobble stones so as the sidewalks some of which do not seem to allow two people side by side. On many streets you have parking on one side and the other is shared by trolleys, cars, buses and delivery trucks. We loved the area which contains a mixed of houses, buildings, businesses and restaurants. It seems like the concept of zoning did not take off in Lisbon. That said, my wife and I loved the city, its people and culture and will be returning for more in a few years. Continue reading “11 to 12 Java Questions”

Porting MD5 Code

Last week my wife and I returned from a one week trip to Portugal. We had not been there in more than a decade. Some things have changed while other not. People continue to be very nice and helpful especially when you attempt to utter a few words in Portuguese.

We arrived in Lisbon and headed to the rental car office. In less than an hour from arrival we were heading south to the Algarve. We have watched a few YouTube videos by Rick Steves and had purchases one of his travel guides for Portugal. In more than one occasion Rick has mentioned that Salema is his favorite beach in the Algarve. By experience we now know why. It is a small town sitting on a relatively small bay with blue and green waters. The population is less than 300 people. My wife took a picture at a restaurant on the beach while the temperature was hitting 96 F and we were enjoying delicious fresh sea food and drinking Sagres beer. From our table we could hear people conversion and different languages. Our waiter was taking care of a few tables and was able to switch to the language spoken by the customers (English, French and German). We only spent two days and headed back to Lisbon. Continue reading “Porting MD5 Code”