Comparator.comparingInt offers a streamlined and efficient way to create comparators based on integer-valued functions. This method, part of the Java Collections Framework, significantly simplifies the process of sorting and comparing objects based on their integer attributes. At COMPARE.EDU.VN, we aim to provide you with detailed comparisons and insights to help you make informed decisions. This article explores the benefits and applications of Comparator.comparingInt, providing a comprehensive comparison to traditional comparator implementations, offering a solution to complex sorting challenges and presenting the comparison essentials.
1. Understanding Comparator and Its Importance
A comparator is an object that defines a comparison between two objects. It’s a fundamental part of the Java Collections Framework, enabling precise control over the sorting order of collections and the behavior of sorted data structures. Let’s delve into what comparators are and why they matter:
1.1 What is a Comparator?
In Java, a Comparator is an interface that defines a method, compare(Object o1, Object o2), which compares two objects and returns an integer indicating their relative order. The return value is:
- Negative if
o1is less thano2. - Zero if
o1is equal too2. - Positive if
o1is greater thano2.
Comparators are used to impose a specific order on a collection of objects, especially when the natural ordering (defined by the Comparable interface) is not suitable or doesn’t exist.
1.2 Why Comparators Matter
Comparators are crucial for several reasons:
- Custom Sorting: They allow you to sort collections based on criteria that are not the natural ordering of the objects. For example, sorting a list of
Personobjects by age, name, or any other attribute. - Data Structures: They control the order of elements in sorted data structures like
TreeSetandTreeMap. - Flexibility: They provide a way to define multiple sorting orders for the same type of objects.
- Algorithm Efficiency: Efficient sorting is essential for many algorithms, and comparators enable the use of optimized sorting methods.
- Business Logic: They allow you to implement complex business rules for ordering data.
1.3 The Traditional Way of Implementing Comparators
Before the introduction of functional interfaces and lambda expressions in Java 8, comparators were typically implemented using anonymous classes or separate class implementations. Here’s an example:
import java.util.Comparator;
public class Person {
private String name;
private int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
public static void main(String[] args) {
Comparator<Person> ageComparator = new Comparator<Person>() {
@Override
public int compare(Person p1, Person p2) {
return Integer.compare(p1.getAge(), p2.getAge());
}
};
}
}This approach is verbose and can be cumbersome, especially for simple comparisons.
2. Introducing Comparator.comparingInt
Comparator.comparingInt is a static method introduced in Java 8 that provides a more concise and readable way to create comparators when comparing objects based on an integer-valued function. It leverages lambda expressions to simplify the comparator creation process.
2.1 Syntax and Basic Usage
The syntax for Comparator.comparingInt is as follows:
public static <T> Comparator<T> comparingInt(ToIntFunction<? super T> keyExtractor)Here, keyExtractor is a function that accepts an object of type T and returns an int. The comparingInt method returns a Comparator<T> that compares objects based on the integer values returned by the keyExtractor function.
Basic Usage Example:
Using the Person class from the previous example, let’s create a comparator to sort Person objects by age using Comparator.comparingInt:
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
public class Person {
private String name;
private int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public int getAge() {
return age;
}
@Override
public String toString() {
return "Person{" +
"name='" + name + ''' +
", age=" + age +
'}';
}
public static void main(String[] args) {
Comparator<Person> ageComparator = Comparator.comparingInt(Person::getAge);
List<Person> people = Arrays.asList(
new Person("Alice", 30),
new Person("Bob", 25),
new Person("Charlie", 35)
);
people.sort(ageComparator);
System.out.println(people); // Output: [Person{name='Bob', age=25}, Person{name='Alice', age=30}, Person{name='Charlie', age=35}]
}
}In this example, Person::getAge is a method reference that serves as the keyExtractor. It extracts the age (an integer) from each Person object. Comparator.comparingInt then uses these integer values to compare the Person objects.
2.2 Benefits of Using Comparator.comparingInt
- Conciseness: It reduces boilerplate code, making the comparator creation process more straightforward.
- Readability: The code is more expressive and easier to understand, as it clearly states the attribute being used for comparison.
- Efficiency: It is optimized for integer comparisons, potentially offering better performance than generic comparators.
- Functional Programming: It aligns with functional programming principles, promoting the use of lambda expressions and method references.
3. Real-World Applications of Comparator.comparingInt
Comparator.comparingInt can be applied in various scenarios where sorting or ordering based on integer attributes is required.
3.1 Sorting a List of Products by Price
Consider a scenario where you have a list of products and you want to sort them by price.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Product {
private String name;
private int price;
public Product(String name, int price) {
this.name = name;
this.price = price;
}
public String getName() {
return name;
}
public int getPrice() {
return price;
}
@Override
public String toString() {
return "Product{" +
"name='" + name + ''' +
", price=" + price +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Product> products = Arrays.asList(
new Product("Laptop", 1200),
new Product("Keyboard", 75),
new Product("Mouse", 25),
new Product("Monitor", 300)
);
Comparator<Product> priceComparator = Comparator.comparingInt(Product::getPrice);
products.sort(priceComparator);
System.out.println(products);
// Output: [Product{name='Mouse', price=25}, Product{name='Keyboard', price=75}, Product{name='Monitor', price=300}, Product{name='Laptop', price=1200}]
}
}In this example, the comparingInt method is used to create a comparator that sorts products based on their prices.
3.2 Sorting Employees by Seniority (Years of Service)
In an HR system, you might want to sort employees based on their years of service.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Employee {
private String name;
private int yearsOfService;
public Employee(String name, int yearsOfService) {
this.name = name;
this.yearsOfService = yearsOfService;
}
public String getName() {
return name;
}
public int getYearsOfService() {
return yearsOfService;
}
@Override
public String toString() {
return "Employee{" +
"name='" + name + ''' +
", yearsOfService=" + yearsOfService +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Employee> employees = Arrays.asList(
new Employee("John", 5),
new Employee("Alice", 10),
new Employee("Bob", 3),
new Employee("Charlie", 7)
);
Comparator<Employee> seniorityComparator = Comparator.comparingInt(Employee::getYearsOfService);
employees.sort(seniorityComparator);
System.out.println(employees);
// Output: [Employee{name='Bob', yearsOfService=3}, Employee{name='John', yearsOfService=5}, Employee{name='Charlie', yearsOfService=7}, Employee{name='Alice', yearsOfService=10}]
}
}Here, comparingInt sorts employees based on their years of service, providing a clear and concise way to define the sorting order.
3.3 Ordering Tasks by Priority
Consider a task management system where tasks have integer priorities.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Task {
private String description;
private int priority;
public Task(String description, int priority) {
this.description = description;
this.priority = priority;
}
public String getDescription() {
return description;
}
public int getPriority() {
return priority;
}
@Override
public String toString() {
return "Task{" +
"description='" + description + ''' +
", priority=" + priority +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Task> tasks = Arrays.asList(
new Task("Implement feature A", 2),
new Task("Fix bug B", 1),
new Task("Write documentation C", 3)
);
Comparator<Task> priorityComparator = Comparator.comparingInt(Task::getPriority);
tasks.sort(priorityComparator);
System.out.println(tasks);
// Output: [Task{description='Fix bug B', priority=1}, Task{description='Implement feature A', priority=2}, Task{description='Write documentation C', priority=3}]
}
}In this case, tasks are sorted by their priority, making it easy to manage and execute them in the correct order.
4. Combining Comparators
One of the powerful features of the Comparator interface is the ability to combine multiple comparators to create more complex sorting orders. This can be achieved using the thenComparing and thenComparingInt methods.
4.1 Using thenComparing and thenComparingInt
The thenComparing and thenComparingInt methods allow you to chain comparators, specifying secondary sorting criteria when the primary criteria result in equal values.
Example:
Let’s extend the Person class to include a last name and sort first by age, then by last name.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Person {
private String firstName;
private String lastName;
private int age;
public Person(String firstName, String lastName, int age) {
this.firstName = firstName;
this.lastName = lastName;
this.age = age;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
public int getAge() {
return age;
}
@Override
public String toString() {
return "Person{" +
"firstName='" + firstName + ''' +
", lastName='" + lastName + ''' +
", age=" + age +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Person> people = Arrays.asList(
new Person("Alice", "Smith", 30),
new Person("Bob", "Johnson", 25),
new Person("Alice", "Brown", 30),
new Person("Charlie", "Williams", 35)
);
Comparator<Person> combinedComparator = Comparator.comparingInt(Person::getAge)
.thenComparing(Person::getLastName);
people.sort(combinedComparator);
System.out.println(people);
// Output: [Person{firstName='Bob', lastName='Johnson', age=25}, Person{firstName='Alice', lastName='Brown', age=30}, Person{firstName='Alice', lastName='Smith', age=30}, Person{firstName='Charlie', lastName='Williams', age=35}]
}
}In this example, the comparingInt method is used to sort first by age, and thenComparing is used to sort by last name when ages are equal.
4.2 Advanced Combinations
You can chain multiple thenComparing and thenComparingInt calls to create even more complex sorting orders. For instance, sorting by age, then by last name, and then by first name:
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Person {
private String firstName;
private String lastName;
private int age;
public Person(String firstName, String lastName, int age) {
this.firstName = firstName;
this.lastName = lastName;
this.age = age;
}
public String getFirstName() {
return firstName;
}
public String getLastName() {
return lastName;
}
public int getAge() {
return age;
}
@Override
public String toString() {
return "Person{" +
"firstName='" + firstName + ''' +
", lastName='" + lastName + ''' +
", age=" + age +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Person> people = Arrays.asList(
new Person("Alice", "Smith", 30),
new Person("Bob", "Johnson", 25),
new Person("Alice", "Brown", 30),
new Person("Charlie", "Williams", 35),
new Person("Alice", "Smith", 25)
);
Comparator<Person> combinedComparator = Comparator.comparingInt(Person::getAge)
.thenComparing(Person::getLastName)
.thenComparing(Person::getFirstName);
people.sort(combinedComparator);
System.out.println(people);
// Output: [Person{firstName='Alice', lastName='Smith', age=25}, Person{firstName='Bob', lastName='Johnson', age=25}, Person{firstName='Alice', lastName='Brown', age=30}, Person{firstName='Alice', lastName='Smith', age=30}, Person{firstName='Charlie', lastName='Williams', age=35}]
}
}This demonstrates the flexibility and power of combining comparators to achieve precise sorting requirements.
5. Null Handling
Handling null values is a common concern when using comparators. The Comparator interface provides methods to handle nulls gracefully.
5.1 Using nullsFirst and nullsLast
The nullsFirst and nullsLast methods allow you to specify how null values should be treated during comparison. nullsFirst places null values at the beginning of the sorted collection, while nullsLast places them at the end.
Example:
Consider a list of employees where some employees may have a null value for their years of service.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
import java.util.Objects;
class Employee {
private String name;
private Integer yearsOfService;
public Employee(String name, Integer yearsOfService) {
this.name = name;
this.yearsOfService = yearsOfService;
}
public String getName() {
return name;
}
public Integer getYearsOfService() {
return yearsOfService;
}
@Override
public String toString() {
return "Employee{" +
"name='" + name + ''' +
", yearsOfService=" + yearsOfService +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Employee> employees = Arrays.asList(
new Employee("John", 5),
new Employee("Alice", 10),
new Employee("Bob", null),
new Employee("Charlie", 7)
);
Comparator<Employee> seniorityComparator = Comparator.comparing(Employee::getYearsOfService, Comparator.nullsLast(Comparator.naturalOrder()));
employees.sort(seniorityComparator);
System.out.println(employees);
// Output: [Employee{name='John', yearsOfService=5}, Employee{name='Charlie', yearsOfService=7}, Employee{name='Alice', yearsOfService=10}, Employee{name='Bob', yearsOfService=null}]
}
}In this example, Comparator.nullsLast is used to place employees with null years of service at the end of the sorted list.
5.2 Combining Null Handling with Integer Comparison
You can combine null handling with comparingInt by first extracting the value and then using nullsFirst or nullsLast.
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Employee {
private String name;
private Integer yearsOfService;
public Employee(String name, Integer yearsOfService) {
this.name = name;
this.yearsOfService = yearsOfService;
}
public String getName() {
return name;
}
public Integer getYearsOfService() {
return yearsOfService;
}
@Override
public String toString() {
return "Employee{" +
"name='" + name + ''' +
", yearsOfService=" + yearsOfService +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Employee> employees = Arrays.asList(
new Employee("John", 5),
new Employee("Alice", 10),
new Employee("Bob", null),
new Employee("Charlie", 7)
);
Comparator<Employee> seniorityComparator = Comparator.comparing(e -> Objects.requireNonNullElse(e.getYearsOfService(), Integer.MAX_VALUE));
employees.sort(seniorityComparator);
System.out.println(employees);
// Output: [Employee{name='John', yearsOfService=5}, Employee{name='Charlie', yearsOfService=7}, Employee{name='Alice', yearsOfService=10}, Employee{name='Bob', yearsOfService=null}]
}
}In this example, we use Objects.requireNonNullElse to replace null values with a default value (in this case, Integer.MAX_VALUE) before comparing.
6. Reverse Order Sorting
Sometimes, you may need to sort in reverse order. The Comparator interface provides methods to achieve this easily.
6.1 Using reversed()
The reversed() method returns a comparator that imposes the reverse order of the original comparator.
Example:
Sorting a list of products by price in descending order:
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Product {
private String name;
private int price;
public Product(String name, int price) {
this.name = name;
this.price = price;
}
public String getName() {
return name;
}
public int getPrice() {
return price;
}
@Override
public String toString() {
return "Product{" +
"name='" + name + ''' +
", price=" + price +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Product> products = Arrays.asList(
new Product("Laptop", 1200),
new Product("Keyboard", 75),
new Product("Mouse", 25),
new Product("Monitor", 300)
);
Comparator<Product> priceComparator = Comparator.comparingInt(Product::getPrice).reversed();
products.sort(priceComparator);
System.out.println(products);
// Output: [Product{name='Laptop', price=1200}, Product{name='Monitor', price=300}, Product{name='Keyboard', price=75}, Product{name='Mouse', price=25}]
}
}Here, reversed() is used to sort the products in descending order of price.
7. Primitive Type Specializations
The Comparator interface provides specialized methods for comparing primitive types such as int, long, and double. These specializations can offer performance benefits by avoiding autoboxing and unboxing.
7.1 comparingLong and comparingDouble
Similar to comparingInt, comparingLong and comparingDouble are used for comparing objects based on long and double values, respectively.
Example:
Sorting a list of items by weight (double):
import java.util.Comparator;
import java.util.Arrays;
import java.util.List;
class Item {
private String name;
private double weight;
public Item(String name, double weight) {
this.name = name;
this.weight = weight;
}
public String getName() {
return name;
}
public double getWeight() {
return weight;
}
@Override
public String toString() {
return "Item{" +
"name='" + name + ''' +
", weight=" + weight +
'}';
}
}
public class Main {
public static void main(String[] args) {
List<Item> items = Arrays.asList(
new Item("Book", 1.5),
new Item("Pencil", 0.1),
new Item("Laptop", 2.2)
);
Comparator<Item> weightComparator = Comparator.comparingDouble(Item::getWeight);
items.sort(weightComparator);
System.out.println(items);
// Output: [Item{name='Pencil', weight=0.1}, Item{name='Book', weight=1.5}, Item{name='Laptop', weight=2.2}]
}
}8. Performance Considerations
While Comparator.comparingInt offers conciseness and readability, it’s important to consider performance implications, especially when dealing with large datasets.
8.1 Autoboxing and Unboxing
When using generic Comparator<T>, autoboxing and unboxing can occur if you are comparing primitive types. This can impact performance, as converting between primitive types and their corresponding wrapper objects (e.g., int to Integer) incurs overhead.
The specialized methods like comparingInt, comparingLong, and comparingDouble avoid this overhead by working directly with primitive types.
8.2 Lambda Expression Overhead
Lambda expressions, while concise, can sometimes introduce a small performance overhead compared to traditional anonymous classes. However, modern JVM implementations often optimize lambda expressions, minimizing this overhead.
8.3 When to Use Specialized Comparators
Use specialized comparators (comparingInt, comparingLong, comparingDouble) when comparing primitive types to avoid autoboxing and unboxing. For complex comparison logic or when dealing with non-primitive types, the generic Comparator<T> may be more appropriate.
9. Best Practices
- Use Method References: Prefer method references (e.g.,
Person::getAge) over lambda expressions when possible, as they are often more readable. - Combine Comparators: Leverage
thenComparingandthenComparingIntto create complex sorting orders. - Handle Nulls: Use
nullsFirstornullsLastto handle null values gracefully. - Consider Performance: Choose specialized comparators for primitive types to avoid autoboxing and unboxing.
- Write Clear Code: Ensure your comparators are easy to understand and maintain.
10. Common Mistakes to Avoid
- Ignoring Null Values: Failing to handle null values can lead to
NullPointerExceptionerrors. - Complex Lambda Expressions: Overly complex lambda expressions can reduce readability.
- Inefficient Comparisons: Avoid performing expensive operations within the comparator.
- Not Using Specialized Comparators: Neglecting to use specialized comparators for primitive types can impact performance.
- Inconsistent Comparisons: Ensure that your comparator provides a consistent and transitive ordering.
11. Use Cases
- E-commerce Platforms: Sorting products by price, rating, or popularity.
- HR Systems: Sorting employees by salary, seniority, or performance.
- Task Management Systems: Ordering tasks by priority, due date, or status.
- Financial Applications: Sorting transactions by date, amount, or type.
- Data Analysis: Ordering data by various metrics for reporting and visualization.
12. Advanced Techniques
- Custom Extraction Logic: Using complex lambda expressions to extract values for comparison.
- Dynamic Comparators: Creating comparators dynamically based on user input or configuration.
- Comparator Composition: Combining multiple comparators to create highly customized sorting orders.
- Parallel Sorting: Using parallel streams to sort large datasets more efficiently.
- Comparator Caching: Caching comparators to avoid repeated creation and improve performance.
13. Related Concepts
- Comparable Interface: The
Comparableinterface defines the natural ordering of objects. - Collections.sort(): A method in the
Collectionsclass used to sort lists. - Arrays.sort(): A method in the
Arraysclass used to sort arrays. - SortedSet and SortedMap: Interfaces that define sorted collections and maps.
- TreeSet and TreeMap: Implementations of
SortedSetandSortedMapthat use comparators to maintain order.
14. Benefits for Different User Groups
- Students (18-24): Comparing universities, courses, and study materials efficiently.
- Consumers (24-55): Sorting and comparing products and services before making a purchase.
- Professionals (24-65+): Comparing methods, technologies, and solutions in their fields.
- Anyone Making Choices: Providing a structured way to evaluate options and make informed decisions.
15. Addressing Customer Challenges
- Objective Comparisons: Providing unbiased comparisons between products, services, and ideas.
- Detailed Information: Offering in-depth analysis of pros and cons, features, specifications, and pricing.
- Simplified Decision-Making: Presenting information in a clear, visual, and easy-to-understand format.
- User Reviews and Expert Opinions: Including feedback from experienced users and industry experts.
- Tailored Recommendations: Helping users identify the best options based on their specific needs and budget.
16. COMPARE.EDU.VN: Your Partner in Informed Decision-Making
At COMPARE.EDU.VN, we understand the challenges of comparing different options and making informed decisions. That’s why we provide comprehensive and objective comparisons across a wide range of products, services, and ideas. Our goal is to empower you with the information you need to make the best choices for your personal and professional life.
17. Conclusion
Comparator.comparingInt is a powerful tool in Java for creating concise, readable, and efficient comparators based on integer-valued functions. It simplifies the process of sorting and ordering collections, making your code cleaner and more maintainable. By understanding its syntax, benefits, and applications, you can leverage Comparator.comparingInt to write more effective and efficient Java code.
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FAQ
1. What is a Comparator in Java?
A Comparator is an interface that defines a method for comparing two objects and determining their relative order. It’s used to sort collections based on custom criteria.
2. What is Comparator.comparingInt?
Comparator.comparingInt is a static method in Java 8 that creates a comparator based on an integer-valued function, providing a concise way to compare objects by an integer attribute.
3. How do I use Comparator.comparingInt?
You use Comparator.comparingInt by passing a method reference or lambda expression that extracts an integer value from the objects being compared.
4. What are the benefits of using Comparator.comparingInt?
The benefits include conciseness, readability, efficiency, and alignment with functional programming principles.
5. Can I combine multiple comparators?
Yes, you can combine comparators using the thenComparing and thenComparingInt methods to create complex sorting orders.
6. How do I handle null values when using comparators?
You can use the nullsFirst and nullsLast methods to specify how null values should be treated during comparison.
7. How do I sort in reverse order?
You can use the reversed() method to obtain a comparator that imposes the reverse order of the original comparator.
8. What are primitive type specializations in comparators?
Primitive type specializations like comparingLong and comparingDouble are used for comparing primitive types directly, avoiding autoboxing and unboxing.
9. What are some common mistakes to avoid when using comparators?
Common mistakes include ignoring null values, using overly complex lambda expressions, and not using specialized comparators for primitive types.
10. Where can I find more information and comparisons to make informed decisions?
Visit compare.edu.vn for detailed comparisons and resources to help you make informed decisions across a wide range of products, services, and ideas.
11. Is Comparator.comparingInt more efficient than a traditional Comparator?
Yes, Comparator.comparingInt is generally more efficient when comparing integer attributes because it avoids autoboxing and unboxing, which can introduce overhead.
12. Can Comparator.comparingInt be used with nullable Integer fields?
Yes, but you need to handle null values explicitly using methods like Objects.requireNonNullElse or Comparator.nullsFirst/Last to avoid NullPointerException.
13. What is the difference between comparingInt, comparingLong, and comparingDouble?
These methods are specialized for comparing int, long, and double primitive types, respectively. They avoid autoboxing and unboxing, providing better performance when working with these types.
14. How can I create a case-insensitive comparator using comparingInt?
Comparator.comparingInt is primarily for integer comparisons. For case-insensitive string comparisons, you would typically use Comparator.comparing(String::toLowerCase) or similar methods.
15. Can I use Comparator.comparingInt with streams?
Yes, Comparator.comparingInt can be used with streams to sort elements based on an integer attribute. For example:
List<Person> sortedPeople = people.stream()
.sorted(Comparator.comparingInt(Person::getAge))
.collect(Collectors.toList());16. How does Comparator.comparingInt handle Integer overflow?
Comparator.comparingInt uses Integer.compare(int x, int y) internally, which correctly handles integer overflow by comparing the values as signed integers.
17. What are the performance implications of using lambda expressions with Comparator.comparingInt?
Lambda expressions can have a slight overhead compared to traditional anonymous classes, but modern JVM implementations often optimize them. The conciseness and readability they provide usually outweigh the performance difference.
18. How can I create a comparator that sorts null values last using Comparator.comparingInt?
You can use Comparator.comparing(e -> e.getYearsOfService() == null ? Integer.MAX_VALUE : e.getYearsOfService()) or Comparator.comparing(Employee::getYearsOfService, Comparator.nullsLast(Comparator.naturalOrder())) where getYearsOfService returns an Integer (nullable).
19. What is the time complexity of sorting using Comparator.comparingInt?
The time complexity of sorting using Comparator.comparingInt depends on the sorting algorithm used by the sort method (e.g., Collections.sort or Arrays.sort). Typically, it is O(n log n) for efficient sorting algorithms like merge sort or quicksort.
20. Can I use Comparator.comparingInt to sort a list of objects in descending order?
Yes, you can use the reversed() method to sort in descending order:
Comparator<YourObject> comparator = Comparator.comparingInt(YourObject::getValue).reversed();
