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

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
jaywengrow
Hello! It’s Jay Wengrow, author of A Common-Sense Guide to Data Structures and Algorithms. My book now has a supplemental website, where ...
New
AstonJ
If you could work on any project, what would it be? :upside_down_face:
New
chasekaylee
Hi there! I have some old Bose in ear noise cancelling headphones that have worked like a champ for the past 3 years and was maybe due fo...
New
DevotionGeo
The Odin programming language is designed with the intent of creating an alternative to C with the following goals: simplicity high per...
New
Margaret
Hello everyone! This thread is to tell you about what authors from The Pragmatic Bookshelf are writing on Medium.
1147 29994 760
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
chaptuck
I am thinking about getting a fitness tracker of some kind (probably one from Garmin). Have any of you developed your own widgets, watchf...
New
AstonJ
I’ve been watching Prag Dave’s Elixir course and I noticed he uses tree: Tree is a recursive directory listing program that produces a ...
New
DevotionGeo
I am planning to refresh my Ruby knowledge in a month or two, after using other technologies more frequently for a few years. Luckily I w...
New

Other popular topics Top

PragmaticBookshelf
Machine learning can be intimidating, with its reliance on math and algorithms that most programmers don't encounter in their regular wor...
New
PragmaticBookshelf
Free and open source software is the default choice for the technologies that run our world, and it’s built and maintained by people like...
New
AstonJ
poll poll Be sure to check out @Dusty’s article posted here: An Introduction to Alternative Keyboard Layouts It’s one of the best write-...
New
AstonJ
This looks like a stunning keycap set :orange_heart: A LEGENDARY KEYBOARD LIVES ON When you bought an Apple Macintosh computer in the e...
New
New
AstonJ
If you want a quick and easy way to block any website on your Mac using Little Snitch simply… File &gt; New Rule: And select Deny, O...
New
New
husaindevelop
Inside our android webview app, we are trying to paste the copied content from another app eg (notes) using navigator.clipboard.readtext ...
New
New
AnfaengerAlex
Hello, I’m a beginner in Android development and I’m facing an issue with my project setup. In my build.gradle.kts file, I have the foll...
New