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Strategy Design Pattern

For example, I have a program with an Animal abstract class and two sub-classes Dog and Bird. I want to add new behavior for the class Animal, this is "fly".  Now, I face two approaches to solve this issue: 1. Adding an abstract method "fly" into the class Animal. Then, I force the sub-classes should be implemented this method, something like: public abstract class Animal{ //bla bla public abstract void fly(); } public class Bird extends Animal{ //bla bla public void fly(){ System.out.println("Fly high"); } } public class Dog extends Animal{ //bla bla public void fly(){ System.out.println("Cant fly"); } } 2. Creating an interface with method "fly" inside. The same issue to an abstract class, I force the classes these implement this interface should have a method "fly" inside: public interface Flyable{ public void fly(); } public class Bird implements Flyable{ //bla bla public void fly(){ System.out.pr
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AngularJS Fundamentals

1. Single Page Application (SPA) - Single page application versus   Traditional multi-page - " Single-Page Applications (SPAs) are Web apps that load a single HTML page and dynamically update that page as the user interacts with the app. SPAs use AJAX and HTML5 to create fluid and responsive Web apps, without constant page reloads. However, this means much of the work happens on the client side, in JavaScript " src:  https://msdn.microsoft.com/en-us/magazine/dn463786.aspx - " Web browser JavaScript frameworks, such as AngularJS, Ember.js, ExtJS and React have adopted SPA principles " src:  https://en.wikipedia.org/wiki/Single-page_application 2. Directive and Data Binding Expression <!DOCTYPE html> <html lang="en-US"> <script src="http://ajax.googleapis.com/ajax/libs/angularjs/1.3.14/angular.min.js"></script> <body> <div ng-app=""> <p>Name : <input type="text" ng
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Build Dynamic Forms in AngularJS Directives

We wanted to build a dynamic form that has some types of elements such as text field, text area, label, date picker, combobox, file uploader, etc. Beside that, the form is dynamic because basing on the provided configuration data, it should render our expected GUI. We conducted a  research with two options: building our own directives or using a third-party directives. - Approach 1: using a third-party directives  + Google keyword: " build dynamic forms directives + angular third party "  + This idea met our idea: " http://blog.backand.com/build-dynamic-forms/ ", but it's not free to use.  + This 3rd-party was possible:  http://schemaform.io/ Schema form hello world app:  http://plnkr.co/edit/7Oqxxl?p=info - Approach 2: building our own directives We chose this approach because it looks more simple than using "schema form" 3rd-party and we thought that we can confidently handle it. Example:   http://codepen.io/cavoirom/pen/meJBxv?edit
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Selenium - tests don't interact with IE

Have you ever faced to a problem that your tests work well on Chrome or Firefox, but don't do anything on Internet Explorer after launching the browser? I have met this issue. Even when my tests have no problems with IE8 but they do not interact with the browser which is upgraded one - IE11, no clicking, no entering anymore. And I got an exception. These below maybe are one of the solutions: 1. Make sure the zoom is 100% (press Ctrl + 0) 2. Uncheck Enable Protected Mode , and set lowest security level too. 3. Add your address to trust sites.
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[Snippet] CSS - Child element overlap parent

I searched from somewhere and found that a lot of people says a basic concept for implementing this feature looks like below: HTML code: <div id="parent">  <div id="child">  </div> </div> And, CSS: #parent{   position: relative;   overflow:hidden; } #child{   position: absolute;   top: -1;   right: -1px; } However, I had a lot of grand-parents in my case and the above code didn't work. Therefore, I needed an alternative. I presumed that my app uses Boostrap and AngularJs, maybe some CSS from them affects mine. I didn't know exactly the problem, but I believed when all CSS is loaded into my browser, I could completely handle it. www.tom-collinson.com I tried to create an example to investigated this problem by Fiddle . Accidentally, I just changed: position: parent; to position: static; for one of parents -> the problem is solved. Look at my code: <div class="modal-body dn-placeholder-parent-position&quo
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From JSP to AngularJS

Our team maintained a project that was used a quite old web technology  JSP . Our project likes a web portal that can contain some other smaller projects, I called it a module. Now, our customers want to add a new module into it. We met a problem is the current projects can't be testable and hard to maintain because both the logic and GUI are mixed together by using JSP and JSTL. It was really a messy project structure. Therefore, we didn't want to continue this approach. Testing is very important, as well as a good structure for maintenance. We would like to apply MVC pattern for testable and maintainable ability purpose. Yeah, that was actually time for changes. Our project structure can't be testable and has poor structure. We listed out some options: Refactoring all current modules -- terrible approach, too much efforts, too risky due to a lot of modules. Using MVC just for the new modules with Servlet for C ontroller, Java class for M odel and JSP for V i
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