In the following example, we sort a list of integers. Main.java import java.util.Arrays; import java.util.Comparator; import java.util.List; void main() { List<Integer> vals = Arrays.asList(5, -4, 0, 2, -1, 4, 7, 6, 1, -1, 3, 8, -2); vals.sort(Comparator.naturalOrder(...
If you're using Java 8, you can even get rid of the aboveFactoryPriceComparatorand use the built-inComparator.comparingDouble(keyExtractor), which creates a comparator comparing the double values returned by the key extractor. In this case, the key extractor could be themethod referenceFactory:...
Comparator is also used for sorting. We can sort list, arrays, Collections using comparator in java. Comparator interface is used to order the objects of user-defined class. The compare Method: int compare(Object obj1, Object obj2) obj1 and obj2 are the objects to be compared. This metho...
For example, you can also useList.sort()method to sort a List of objects. This is similar toCollections.sort()and you can use it to sort a list of objects using both Comparator and Comparable. This method accepts a Comparator and sorts elements based upon that, but if you want to sort...
java.util.Collections.sort(List) and java.util.Arrays.sort(Object[]) methods can be used to sort using natural ordering of objects. java.util.Collections.sort(List, Comparator) and java.util.Arrays.sort(Object[], Comparator) methods can be used if a Comparator is available for comparison. ...
In this tutorial, we’ll discuss sorting objects in aListby date. Most of the sorting techniques or examples let the user sort a list alphabetically, but in this article, we’ll discuss how to do it withDateobjects. We’ll look at using Java’sComparatorclass forcustom sorting our lists...
to another order than their natural order. Perhaps the objects you are sorting do not even have a natural order. In that case you can use aComparatorinstead. See theJava Comparatortutorial for more information about the Comparator interface. Here is how you sort a list using aComparator: ...
UsingComparatorwith lambda expressions Sorting with Comparable We’ll start with how to sort using Java’sComparableinterface. We useComparablewhen there is a single, default comparison for the object we want sorted. Sorting a Java List In this first example, we implementComparablein aSimp...
You don't actually have to create a comparator class, however. A lambda which takes two arguments and returns an integer can be a Comparator. This is valid, and will actually reverse your list: ? 1 Comparator<String> NumberStringComparator = (a, b) -> -1;Here is an example of using ...
Java Sorting Guides Java Comparator Tutorials How to Sort an Array, List, Map or Stream in Java Learn to sort a Java Set, List and Map of primitive types and custom objects using Comparator, Comparable and new lambda expressions. We will learn to sort in ascending and descending order as ...