harwind

harwind

Java's for each loop

So, basically, I’m writing a method to check application numbers in my array ‘applications,’ and this method receives a parameter to verify that specific application number and compares it to the application numbers in the list.
So first look at the code:

public boolean hasApplicationNumber(int number) {
    if (number <= 3 ) {
        throw new IllegalArgumentException("bad number");   
    }

    for (ApplicationData current : applications) {
        if (number == current.getApplicationNumber() ) {    
            return true;
        }
    }
    return false;
}  

JUnit test to validate the application number:

public void shouldHaveApplicationNumber1() {
    University westGeorgia = new University("West Georgia");
    ApplicationData student1 = new ApplicationData(9, 7.0, 400);
    westGeorgia.addApplication(student1);
    assertEquals(true, westGeorgia.hasApplicationNumber(1));
}

This JUnit test is failing because my code returns “false” instead of “true.”

However, if I change the return values in my “hasApplicationNumber” method to true (at the very bottom of the method), this test will pass, but another test I have (that doesn’t allow the list to exceed 10) will return “true” when it is supposed to be “false,” causing that test to fail (I didn’t include that test because it is very similar to the one I have already provided — just “1” is changed to “10” and “true”
I’m beginning to suspect that either my test is being ignored by the Java compiler, or my for-each loop is executing correctly and returning “true,” but since I followed this documentation, I have that lingering false at the very end, which may be declaring the item false nonetheless.

I might be overthinking this, but I’m at a loss on how to change the for-each loop in the method I wrote. Any assistance in sorting this out would be much appreciated!

Most Liked

dtonhofer

dtonhofer

This JUnit test is failing because my code returns “false” instead of “true.”

Isn’t the JUnit test failing because the

hasApplicationNumber(1)

throws?

At this point, the easiest way to unconfuse yourself is to add a few print statements into the test code.

System.out.println("After test for throw );

etc.

finner

finner

hi @harwind -
According to the code you have pasted when you pass 1 into the method hasApplicationNumber an IllegalArgumentException will be thrown. So the test should fail.
I’ve also noticed that you are using double in the ApplicationData class but treating them as int in the hasApplicationNumber method.
Here is a stripped down version without the ApplicationData class and using int.

public class DevTalkTest {

    private final int[] numbers = new int[]{9, 7, 400};

    @Test
    public void shouldHaveApplicationNumber1() {
        assertTrue(hasApplicationNumber(1));
    }


    public boolean hasApplicationNumber(int number) {
        if (number <= 3) {
            throw new IllegalArgumentException("bad number");
        }
        for (int num : numbers) {
            if (num == number) return true;
        }
        return false;
    }


}

The tests will fail with the error:

bad number
java.lang.IllegalArgumentException: bad number
. . . 
finner

finner

I was going to suggest setting a breakpoint on the last line.

Where Next?

Popular General Dev topics Top

AstonJ
If you had the ear of a language creator, what would you say - what could they do to make a language that you would use? :upside_down_face:
New
Rainer
Have you seen the new features that will be available in the upcoming C# 9 release? C# is taking a lot of input from functional l...
New
wolf4earth
Inspired by this thread about arcade games - which I initially misread as favorite arcade game soundtracks - I wanted to ask about your f...
New
dasdom
No chair. I have a standing desk. This post was split into a dedicated thread from our thread about chairs :slight_smile:
New
AstonJ
Curious to know which languages and frameworks you’re all thinking about learning next :upside_down_face: Perhaps if there’s enough peop...
New
finner
When you are under pressure to deliver you ideally want your Pull Request to be reviewed, approved and merged as quick as possible. So do...
New
AstonJ
Do the test and post your score :nerd_face: :keyboard: If possible, please add info such as the keyboard you’re using, the layout (Qw...
New
AstonJ
Maybe a specific language or framework? Or a book or tool perhaps? What’s made your life easier and what do you think could make the live...
New
jaeyson
Hi!, hope everyone’s ok. Sorry if this question is ambiguous (i’ll remove this if i break some rules here). This is more like a self-ques...
New
Maartz
Hey, I love Regex, letting my kids slaming the keyboard until finding the good regex to do the job has always been a source of joy and p...
New

Other popular topics Top

ohm
Which, if any, games do you play? On what platform? I just bought (and completed) Minecraft Dungeons for my Nintendo Switch. Other than ...
New
DevotionGeo
I know that -t flag is used along with -i flag for getting an interactive shell. But I cannot digest what the man page for docker run com...
New
PragmaticBookshelf
From finance to artificial intelligence, genetic algorithms are a powerful tool with a wide array of applications. But you don't need an ...
New
AstonJ
There’s a whole world of custom keycaps out there that I didn’t know existed! Check out all of our Keycaps threads here: https://forum....
New
New
AstonJ
Saw this on TikTok of all places! :lol: Anyone heard of them before? Lite:
New
New
hilfordjames
There appears to have been an update that has changed the terminology for what has previously been known as the Taskbar Overflow - this h...
New
PragmaticBookshelf
Get the comprehensive, insider information you need for Rails 8 with the new edition of this award-winning classic. Sam Ruby @rubys ...
New
PragmaticBookshelf
Use advanced functional programming principles, practical Domain-Driven Design techniques, and production-ready Elixir code to build scal...
New