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Showing posts with the label Object-Oriented Programming

Java Keywords (Part XVI): The many uses of the super keyword

We are up to 40 keywords covered in previous articles! That's 83% keywords covered. We have only 8 keywords to cover and I will be covering 1 of those in this article. We are almost done with all the basic keywords. This article will illustrate the use of the keyword super . I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords already covered may be used in code examples illustrated here. Java keyword list abstract continue for new switch assert default goto * package synchronized boolean do if private this break double implements protected throw ...

Java Keywords (Part XV): The many uses of the this keyword

We are up to 39 keywords covered in previous articles! That's 81% keywords covered. We have only 9 keywords to cover and I will be covering 1 of those in this article. We are almost done with all the basic keywords. This article will illustrate the use of the keyword this . I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords already covered may be used in code examples illustrated here. Java keyword list abstract continue for new switch assert default goto * package synchronized boolean do if private this break double implements protected throw ...

Java Keywords (Part XIV): Using the instanceof Operator

We are up to 38 keywords covered in previous articles! That's 79% keywords covered. We have only 10 keywords to cover and I will be covering 1 of those in this article. We are almost done with all the basic keywords. This article will illustrate the use of the keyword instanceof . I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords already covered may be used in code examples illustrated here. Java keyword list abstract continue for new switch assert default goto * package synchronized boolean do if private this break double implements protected ...

Application of the Builder Pattern

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Using Builder Pattern with Class Hierarchies

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Static Factory Method

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The Builder Pattern (using immutability)

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The Beauty of the Null Object Pattern

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Before we start... Let me start by saying this: NEVER dismiss an idea without giving it any consideration. That was the mistake I made when I first encountered an article about this design pattern many years ago. I was thrown off by the name and without even attempting to find out what this design pattern was all about, I moved on to other things. That was a huge mistake and I am not afraid to admit it. I urge you not to make that mistake. And if you have already, never make that mistake again. Trust me, you will thank me later. For now, let me tell you my story and attempt to explain when to use it along with a simple example on how to implement this pattern. The Null Object Pattern By definition, the main purpose of this pattern is to have an Object-Oriented alternative to the absence of objects by creating objects that display "do nothing" behavior. That sounds like a mouthful. In simplest terms, it is meant to provide a mechanism to replace null references w...

Java Keywords (Part XII): Implementing Interfaces and Extending Classes

We are up to 34 keywords covered in previous articles! That's 71% keywords covered. We have only 16 keywords to cover and I will be covering 2 of those in this article. This article will illustrate the use of the keywords implements and extends for implementing functionality outlined in interfaces as well as extending the functionality of a class. I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords already covered may be used in code examples illustrated here. Java keyword list abstract continue for new switch assert default goto * package synchronized ...

Java Keywords (Part XI): Throwing Exceptions

We are up to 32 keywords covered in previous articles! That's 67% keywords covered. We have only 16 keywords to cover and I will be covering 2 of those in this article. This article will illustrate the use of the keywords throw and throws , in Java Exception Handling. It will not get into specific usages of Exception Handling. For that, please go to my article covering this topic. Also, be on the lookout for a new article covering other facets of Java Exception Handling, such as "try with resources." I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords already co...

Java Keywords (Part X): Try, Catch, and Finally Blocks

We are up to 29 keywords covered in previous articles! That's 60% keywords covered. We have only 19 keywords to cover and I will be covering 3 of those in this article. This article will illustrate the use of the keywords try , catch , and finally , in Java Exception Handling. It will not get into specific usages of Exception Handling. For that, please go to my article covering this topic. Also, be on the lookout for a new article covering other facets of Java Exception Handling, such as "try with resources." I suggest you start with Java Keywords (Part I) before proceeding further, if you have not read any of the previous articles in the Java Keyword series. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. The series was written with natural progression in mind. Therefore, some of the keywords al...

Object-Oriented Programming Basics: What is in a Class?

EDITORIAL NOTE : This article was published briefly back in 2016 and quickly set back to draft because I wasn't happy with its contents. It is a shame that it was taking me three years to revisit this topic and work on a new and improved version. At least, I'm hoping it will be to the liking you the reader. Keep in mind that the opening paragraph will still read as if I just wrote it for my (former) students at Texas Wesleyan. I started working on lecture on the topic of Object-Oriented (OO) Programming by gathering some material, old and new, when I realized this might be good and simple post for my second attempt at blogging. To be completely honest, in the 8 hours I spent collecting information and preparing material for this week's lecture, I realized I still made some of the mistakes I am about to blog about. I am actually hoping I can write a series of postings regarding Object-Oriented Programming (OOP). But to do so, I must start from the very beginning. ...

Java Keywords (Part VII): Loops

The Java keyword list has 21 keywords grayed out. That puts us at 42% of keywords covered by these series of articles. Amazingly, that's almost enough knowledge to built simple applications. I suggest that if you have not read any of the articles in Java Keyword series, go back read them before proceeding further. Also, go back and read the one about Data Types. All of these articles are from September 2018. That should help you find them quickly. You can also use the "search" option at the top of this page. This article will cover the keywords used for looping: for , do , and while , as well as the keywords used to change the flow of loops: break and continue . Java keyword list abstract continue for new switch assert default goto * package synchronized boolean do if private this break double implements protected throw byte else import public throws case enum instanceof return transient catch extends int ...