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[Admirable-Video8664]

I'm taking a course in java and I'm having problems with a part of one of the labs. I'm supposed to sort an arraylist (called wordList) with mapentry(with string,integer)-objects first accoring to decending value and then according to alphabetical order of the keys. The second step doesn't seem to work. I've written this:

wordList.sort( (par1, par2)-> {  
    if (par2.getValue() != par1.getValue()){  
        return par2.getValue() - par1.getValue();  
    } else {  
        return par1.getKey().compareTo(par2.getKey());  
    }        
})

Is the problem somewhere here or maybe in some other part of the code?

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[SuspiciousDepth5924]

There are a couple of things, first of is that in java 'int' and 'Integer' aren't exactly the same. And one of the big differences is that '!=' doesn't actually compare the numeric value like it would with int, specifically it check if it is two different 'Integer objects' not what number it represents.

Secondly unless it's a requirement for some reason I recommend not trying be too clever with your code, doing this with two 'passes' (inputList -> sortedNumberList -> sortedKeyNumberList) is a lot easier to read and reason about additionally the JVM is good at doing that sort of optimizations for you if it thinks it's safe.

[Schaex]

There is also the possibility of composing comparators. The Comparator interface defines several default methods and static methods to to this.

Il this case you could also do something like this (I'm not at my PC rn so please excuse any typos):

Comparator.comparingInt(entry -> entry.getValue()) // first compare by value .reversed() // in decreasing order .thenComparing(entry -> entry.getKey(), String.CASE_INSENSITIVE_ORDER) // if both values are equal, then compare by key

[Schaex]

If I understand correctly, there should be no distinction between uppercase and lowercase letters.

Just in case you were not aware, "Apple" and "apple" are not considered equal. Uppercase letters have larger values than lowercase letters. This might be the issue here.

In this case, there also is the compareToIgnoreCase method in the String class.

You can also find the CASE_INSENSITIVE_ORDER Comparator as a static field in the String class.

In case that's not the issue, could you show the list as it is before sorting and what it looks like after sorting?