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

Devtalk
Hello Devtalk World! Please let us know a little about who you are and where you’re from :nerd_face:
New
AstonJ
A thread that every forum needs! Simply post a link to a track on YouTube (or SoundCloud or Vimeo amongst others!) on a separate line an...
New
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
AstonJ
Always interested in seeing what apps people use and how they organise their phones/home screens! Here’s mine…
New
AstonJ
Great paper by Igor Kopestenski on Erlang and GRiSP: Erlang as an Enabling Technology for Resilient General-Purpose Applications on Edge ...
New
DevotionGeo
The V Programming Language Simple language for building maintainable programs V is already mentioned couple of times in the forum, but I...
New
Exadra37
A modern streaming platform for mission critical workloads Redpanda is a Kafka® compatible event streaming platform. No Zookeeper®, no JV...
New
malloryerik
With 100% less blockchain. I went searching for a lightweight immutable database that could be audited and ran into this. I guess this ...
New
AstonJ
Chris Seaton, the creator of TruffleRuby has died. It appears from suicide :cry: He left this note on Twitter on the weekend: And one...
New
DevotionGeo
Amazon CodeWhisperer is an alternative to GitHub Copilot, and it’s free!
New

Other popular topics Top

PragmaticBookshelf
Brace yourself for a fun challenge: build a photorealistic 3D renderer from scratch! In just a couple of weeks, build a ray tracer that r...
New
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
AstonJ
If you are experiencing Rails console using 100% CPU on your dev machine, then updating your development and test gems might fix the issu...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
AstonJ
Saw this on TikTok of all places! :lol: Anyone heard of them before? Lite:
New
Maartz
Hi folks, I don’t know if I saw this here but, here’s a new programming language, called Roc Reminds me a bit of Elm and thus Haskell. ...
New
PragmaticBookshelf
Rails 7 completely redefines what it means to produce fantastic user experiences and provides a way to achieve all the benefits of single...
New
PragmaticBookshelf
Author Spotlight Rebecca Skinner @RebeccaSkinner Welcome to our latest author spotlight, where we sit down with Rebecca Skinner, auth...
New
PragmaticBookshelf
Fight complexity and reclaim the original spirit of agility by learning to simplify how you develop software. The result: a more humane a...
New