package MyLambdaPipeline2;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Consumer;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.stream.Collectors;

public class LambdaTests {
	public static void main(String[] args) {
		MyFunctionInterfaceA f1 = (x, y) -> x + y;
		MyFunctionInterfaceA f2 = (x, y) -> x - y + 200;
		MyFunctionInterfaceB f3 = (x, y) -> x > y;
		MyFunctionInterfaceC f4 = x -> {
			double y = 1.5 * x;
			return y + 8.0;
		};

		System.out.println(f1.myCompute(10, 20)); // prints 30
		System.out.println(f2.myCompute(10, 20)); // prints 190
		System.out.println(f3.myCmp(10, 20)); // prints false
		System.out.println(f4.doSomething(10)); // prints 23.0

		Function<String, Integer> func = x -> x.length();
		Integer answer = func.apply("Sydney");
		System.out.println(answer); // prints 6

		Function<String, Integer> func1 = x -> x.length();
		Function<Integer, Boolean> func2 = x -> x > 5;
		Boolean result = func1.andThen(func2).apply("Sydney");
		System.out.println(result);

		Predicate<Integer> myPass = mark -> mark >= 50;
		List<Integer> listMarks = Arrays.asList(45, 50, 89, 65, 10);
		List<Integer> passMarks = listMarks.stream().filter(myPass).collect(Collectors.toList());

		System.out.println(passMarks); // prints [50, 89, 65]

		Consumer<String> print = x -> System.out.println(x);
		print.accept("Sydney"); // prints Sydney

		// Consumer to multiply 5 to every integer of a list
		Consumer<List<Integer>> myModifyList = list -> {
			for (int i = 0; i < list.size(); i++)
				list.set(i, 5 * list.get(i));
		};

		List<Integer> list = new ArrayList<Integer>();
		list.add(5);
		list.add(1);
		list.add(10);

		// Implement myModifyList using accept()
		myModifyList.accept(list);

		// Consumer to display a list of numbers
		Consumer<List<Integer>> myDispList = myList -> {
			myList.stream().forEach(e -> System.out.println(e));
		};
		// Display list using myDispList
		myDispList.accept(list);

		List<String> strList = new ArrayList<String>();
		strList.add("Sydney");
		strList.add("");
		strList.add("Brisbane");
		strList.add("Perth");
		strList.add("");
		strList.add("");
		strList.add("Melbourne");

		System.out.println("------- +++++++++++ ----------");

		Predicate<String> p = String::isEmpty;

		// Collect empty strings
		List<String> strEmptyList1 = strList.stream().filter(p).collect(Collectors.toList());

		System.out.println("Number of empty strings: " + strEmptyList1.size());
		// prints 3

		// Collect strings with length less than six
		List<String> strEmptyList2 = strList.stream().filter(e -> e.length() < 6).collect(Collectors.toList());

		System.out.println("Number of strings with length < 6: " + strEmptyList2.size());
		// prints 4

		strList.stream().filter(e -> e.length() >= 6).forEach(e -> System.out.println(e));
		/** prints
		 * Sydney
		 * Brisbane
		 * Melbourne
		 */

		double avgNonEmptyStrLen = strList.stream()
				.filter(e -> e.length() > 0)
				.mapToInt(String::length)
				.average()
				.getAsDouble();

		System.out.println("avgNonEmptyStrLen: " + avgNonEmptyStrLen);
		/** prints
		 * 7.0
		 */
	}
}