How can I correctly implement the methods in my class?-CodePudding

I have a class SimpHisto that takes in an array of generic type SL, and returns the size and the count of a specific element of that array. After I tried to run my code, I get an error saying:

> Task :compileJava UP-TO-DATE
> Task :processResources UP-TO-DATE
> Task :classes UP-TO-DATE
> Task :compileTestJava
> Task :processTestResources NO-SOURCE
> Task :testClasses
> Task :test FAILED

No element at index

Can someone please explain what's wrong with my code and provide any explanations on solutions?

Thank you

CodePudding user response：

The error is in your Iterate. You throw that exception if (index <= items.length). index starts with 0 so this is always true. You only have to change to >=

As mentioned by 英語は苦手 your while in getCount does not call next. Since you iterate over the items directly I would prefer to remove the Iterator at all. And a Stream may increase readability:

return (int) Stream.of(this.items)
    .filter(dt -> dt == item)
    .count();

EDIT: without Stream-API you can iterate over your items directly:

for (SL dt : this.items) {
    if (dt == item) {
        n  ;
    }
}

If you want to use the Iterator you have to call next

while (L.hasNext()) {
    SL dt = L.next();
    if (dt == item) {
        n  ;
    }
}

BTW: why assertEquals(3, elemCount);? There are 4 elements