Skip to main content

A simple way to mock objects without using mock unit testing framework

When writing unit test, there are some cases that I have to mock objects:
  1. It makes sense to mock provided objects by libraries (APIs) such as FacesContext (JSF) because of no real environment running.
  2. It makes sense to mock a lower layer objects and it is already tested, for example: mocking Dao layer objects when testing Service layer (Service calls Dao).
At beginning I was aware of Mockito (a mocking framework) in order to overcome the issue. And currently, I am interested in another way like an alternative because it looks more simple. That is just create mock objects manually and just do anything we want. I've just known this approach from Primefaces' source code. :)

Follow my simple example below and we can see what different from these 2 ways are:

I have an interface Foo and a class Bar

public interface Foo {
    String greet();
}

public class Bar {
    public String greet(Foo foo){
        return foo.greet();
    }
}

Using Mockito example:

public class MockitoExampleTest {
    private Foo foo;
    
    @Before
    public void setup(){
        foo = Mockito.mock(Foo.class);
        Mockito.when(foo.greet()).thenReturn("Hello world!");
    }
   
    @Test
    public void barGreets(){
        Bar bar = new Bar();
        Assert.assertEquals(bar.greet(foo), "Hello world!");
    }
}

Simple mock example:

public class FooMock implements Foo {

    public String greet() {
        return "Hello world!";
    }

}

public class SimpleMockExampleTest {
    private Foo foo;
   
    @Before
    public void setup(){
        foo = new FooMock();
    }
   
    @Test
    public void barGreets(){
        Bar bar = new Bar();
        Assert.assertEquals(bar.greet(foo), "Hello world!");
    }
}

The following is Primefaces' test code that shows the same idea above:

FacesContext context = new FacesContextMock(attributes); 
context.setViewRoot(new UIViewRoot());

References:
[1]. https://examples.javacodegeeks.com/core-java/mockito/mockito-hello-world-example/ 
[2]. https://github.com/primefaces/primefaces

Comments

Popular posts from this blog

[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-positi...

Selenium - Use Explicit Waits for checking elements quickly disappear like loading icon

I have a table that is displayed a list of competence groups. When I click on a competence group, it will display a table that contains a lot of criteria belong to the competence group. Each times I click on a competence group, a "loading" icon is displayed while waiting for all criteria is fully displayed. <div id="loading" style="display: none;"> <div></div> <div></div> I tried to write a Selenium test to make sure this behavior is covered. I saw that the loading icon element is always available on DOM tree because I just used Jquery to handle its displaying. Beside that, the loading icon is appeared dynamically and quickly disappear afterwards. It is hard to checking the visibility on GUI of loading icon. By normal way that I frequently used, the code looks like: public boolean isLoadingIconDisplayed() { List<WebElement> loadingIcons = driver.findElements(By.id("loading")); if(!loadingIcons.isE...

The HelloWorld example of JSF 2.2 with Myfaces

I just did by myself create a very simple app "HelloWorld" of JSF 2.2 with a concrete implementation Myfaces that we can use it later on for our further JSF trying out. I attached the source code link at the end part. Just follow these steps below: 1. Create a Maven project in Eclipse (Kepler) with a simple Java web application archetype "maven-archetype-webapp". Maven should be the best choice for managing the dependencies , so far. JSF is a web framework that is the reason why I chose the mentioned archetype for my example. 2. Import dependencies for JSF implementation - Myfaces (v2.2.10) into file pom.xml . The following code that is easy to find from  http://mvnrepository.com/  with key words "myfaces". <dependency> <groupId>org.apache.myfaces.core</groupId> <artifactId>myfaces-api</artifactId> <version>2.2.10</version> </dependency> <dependency> <groupId>org.apache.myfaces.core<...

Separate Constructing a System from Using It

I n the real world, in order to use a building (hotel, supermarket, etc) we need to construct it first. This concern should be applied for software development as well. Step by step, I would like to show you the issue about no separation of constructing and using it and then I'll give you some approaches to overcome this issue. | Note : you can find the  below  demonstrated code here    Take a Look the Following Simple Application Used tools and technologies: Eclipse (Mars), JDK 1.8 I had an App which uses Controller . Controller uses Service (an interface). Finally, Service has one concrete class is DefaultService . //package vn.nvanhuong.system.separationconstructing; public class App { public static void main(String[] args) { Controller controller = new Controller(); controller.doAction(); } } public class Controller { private Service service; public void doAction(){ System.out.println("doAction in Controller"); getService().execut...

Styling Sort Icons Using Font Awesome for Primefaces' Data Table

So far, Primefaces has used image sprites for displaying the sort icons. This leads to a problem if we want to make a different style for these icons; for example, I would make the icon "arrow up" more blurry at the first time the table loading because I want to highlight the icon "arrow down". I found a way that I can replace these icons with Font Awesome icons. We will use "CSS Pseudo-classes" to achieve it. The hardest thing here is that we should handle displaying icons in different cases. There is a case both "arrow up" and "arrow down" showing and other case is only one of these icons is shown. .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s { background-image: none; margin-left: 5px; font-size: 1.1666em; position: relative; } .ui-sortable-column-icon.ui-icon.ui-icon-carat-2-n-s:not(.ui-icon-triangle-1-s)::before { content: "\f106"; font-family: "FontAwesome"; position: ...