Answer to Question #261975 in Java | JSP | JSF for ....

Question

### Functional Interfaces and Lambda Expressions

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1. In the class LambdaExercise, create following static variables

1. countries of type List<String>

2. countryCapitals of type Map<String, String>

In a static block, initialize countries and countryCapitals with soe values

Define following static methods and provide the implementation as given below

- sortCountriesBylength

- Sort the List using Comparator, in descending order of number of characters in the country name.

If the number of characters are same for a country, it should be sorted alphabetically

(Use Comparator's static/default methods)

- removeCountry(String name)

- remove the countries whose name is greater than 6 characters

Execute the methods and display the results in main method

Answer 1

import java.util.List;
public class Main{
	public static int getPop_Loop(List<Country> countries, String conti) {
		int totalP = 0;
		for (Country country : countries) {
			if (country.getContinent().equalsIgnoreCase(conti)) {
				totalP += country.getPop();
			}
		}
		return totalP;
	}
	public static int getPop_Lambda(List<Country> countries, String conti) {
		return countries.stream().filter(country -> country.getContinent().equalsIgnoreCase(conti)).mapToInt(Country::getPop).sum();
	}


	public static class Country {


		private String conti;
		private int popu;


		public Country(String conti, int popu) {
			this.conti = conti;
			this.popu = popu;
		}


		public String getContinent() {
			return conti;
		}
		public void setContinent(String conti) {
			this.conti = conti;
		}


		public int getPop() {
			return popu;
		}
		public void setPop(int popu) {
			this.popu = popu;
		}


	}
}