Java array list from a class

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soniajain

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Hi everybody!

I need to sort an Array List from a class.
I did this with "Collections.sort(ArrayList);" tried.
Yet, that doesn't work since it is by all accounts some unacceptable data type.
Double values are stored in this array list.

How could you at any point respond there?
 

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that doesn't work since it is by all accounts some unacceptable data type.
Click to expand...
One would expect to see the code and the specific compiler error you are talking about, not the narrative about whatever you meant.
Anyway, are you trying to sort values from different types?
 

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By default, the sort() function sorts the values in string order. This function works great for strings ("apple" will come before "banana").
However, if the numbers are sorted by string, "25" is greater than "100" because "2" is greater than "1". Therefore, the sort() method may produce incorrect results when sorting numeric values.

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To sort an ArrayList of Double values in Java using Collections.sort, you should ensure that the ArrayList is of type Double (i.e., ArrayList<Double>) and not a raw ArrayList type. Here's the correct way to sort an ArrayList of Double values:

Java: 
import java.util.ArrayList;
import java.util.Collections;

public class Main {
    public static void main(String[] args) {
        ArrayList<Double> doubleList = new ArrayList<>();

        // Add double values to the ArrayList
        doubleList.add(3.5);
        doubleList.add(1.2);
        doubleList.add(2.7);
        doubleList.add(0.8);

        // Sort the ArrayList
        Collections.sort(doubleList);

        // Print the sorted ArrayList
        for (Double value : doubleList) {
            System.out.println(value);
        }
    }
}

Make sure that your ArrayList is explicitly typed as ArrayList<Double>. This code will sort the ArrayList of Double values in ascending order. If you want to sort in descending order, you can use the Collections.reverse() method after sorting.
 

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