package Java8Test;

import java.util.Arrays;

import java.util.IntSummaryStatistics;

import java.util.List;

import java.util.Random;

import java.util.stream.Collectors;

/**

* @Classname StreamTest

* @Description TODO

* @Date 19-7-5 上午11:00

* @Created by mao<tianmao818@qq.com>

*/

public class StreamTest {

public static void main(String[] args){

List<String> strings = Arrays.asList("abc", "", "bc", "efg", "abcd","", "jkl");

List<Integer> numbers = Arrays.asList(3, 2, 2, 3, 7, 3, 5);

List<Integer> integers = Arrays.asList(1,2,13,4,15,6,17,8,19);

Random random = new Random();

System.out.println("使用 Java 8: ");

System.out.println("列表: " +strings);

long count = strings.stream().filter(string->string.isEmpty()).count();

System.out.println("空字符串数量为: " + count);

count = strings.stream().filter(string -> string.length() == 3).count();

System.out.println("字符串长度为 3 的数量为: " + count);

List<String> filtered = strings.stream().filter(string ->!string.isEmpty()).collect(Collectors.toList());

System.out.println("筛选后的列表: " + filtered);

String mergedString = strings.stream().filter(string ->!string.isEmpty()).collect(Collectors.joining(", "));

System.out.println("合并字符串: " + mergedString);

List<Integer> squaresList = numbers.stream().map( i ->i*i).distinct().sorted().collect(Collectors.toList());

System.out.println("平方后并排序的列表: " + squaresList);

System.out.println("列表: " +integers);

IntSummaryStatistics stats = integers.stream().mapToInt((x) ->x).summaryStatistics();

System.out.println("列表中最大的数 : " + stats.getMax());

System.out.println("列表中最小的数 : " + stats.getMin());

System.out.println("所有数之和 : " + stats.getSum());

System.out.println("平均数 : " + stats.getAverage());

System.out.println("随机数: ");

random.ints().limit(10).sorted().forEach(System.out::println);

// 并行处理

count = strings.parallelStream().filter(string -> string.isEmpty()).count();

System.out.println("空字符串的数量为: " + count);

}

}