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
Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...
1050 21151 394
New
AstonJ
The obligatory speed test thread :smiley: Check here: https://www.speedtest.net When complete, click on the share link and copy and pas...
New
AstonJ
Which screen resolutions do you frequently use? Note: not the resolution the display is capable of mind, but the resolution you’re using...
New
AstonJ
If so, what was the last blog post you wrote… and if not, why not?
New
Exadra37
Have you ever wanted to build something but you had no idea what to do? Just as authors sometimes have “writers block” it’s also true for...
New
New
AstonJ
Are you a touch typist? :keyboard: poll If you haven’t checked your typing speed yet, you can do so here here :smiley:
New
Exadra37
A modern streaming platform for mission critical workloads Redpanda is a Kafka® compatible event streaming platform. No Zookeeper®, no JV...
New
Exadra37
Kubernetes is everywhere. Transactional apps, video streaming services and machine learning workloads are finding a home on this ever-gro...
New
New

Other popular topics Top

Devtalk
Reading something? Working on something? Planning something? Changing jobs even!? If you’re up for sharing, please let us know what you’...
1050 21151 394
New
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
AstonJ
Or looking forward to? :nerd_face:
490 12945 266
New
AstonJ
I have seen the keycaps I want - they are due for a group-buy this week but won’t be delivered until October next year!!! :rofl: The Ser...
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
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
AstonJ
Was just curious to see if any were around, found this one: I got 51/100: Not sure if it was meant to buy I am sure at times the b...
New
PragmaticBookshelf
Author Spotlight Jamis Buck @jamis This month, we have the pleasure of spotlighting author Jamis Buck, who has written Mazes for Prog...
New
New
AstonJ
This is cool! DEEPSEEK-V3 ON M4 MAC: BLAZING FAST INFERENCE ON APPLE SILICON We just witnessed something incredible: the largest open-s...
New