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Java / Java8 streams

One programming question related to Java streams. I have an Array of Employees object (includes empName, sex, age, city). Can you write a Java program using Java streams concepts to find the number of Employees in each City? For example, Employees in Mumbai: 35 like that. Thanks in Advance.

Thanks for your question. Consider the below example. Kindly share your feedback/suggestions in the comment section.

package net.javapedia.streams;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

class Employee {
	public Employee(String empName, Sex sex, String city) {
		super();
		this.empName = empName;
		this.sex = sex;
		this.city = city;
	}

	String empName;

	public String getEmpName() {
		return empName;
	}

	Sex sex;
	String city;

	public String getCity() {
		return city;
	}

}

enum Sex {
	M, F;
}

public class GroupbyCountingExample {

	public static void main(String[] str) {

		List<Employee> myEmployees = new ArrayList<>();
		myEmployees.add(new Employee("Name1", Sex.M, "New York"));
		myEmployees.add(new Employee("Name2", Sex.F, "Dallas"));
		myEmployees.add(new Employee("Name3", Sex.F, "Charlotte"));
		myEmployees.add(new Employee("Name4", Sex.F, "Charlotte"));
		myEmployees.add(new Employee("Name5", Sex.M, "New York"));
		myEmployees.add(new Employee("Name5", Sex.M, "New York"));

		Map<String, Long> empCountByCity = myEmployees.stream()
				.collect(Collectors.groupingBy(Employee::getCity, Collectors.counting()));

		for (String city : empCountByCity.keySet()) {
			System.out.println("Employee count in " + city + " :" + empCountByCity.get((city)));
		}

	}

}

Output:
Employee count in New York :3
Employee count in Charlotte :2
Employee count in Dallas :1

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