集合操作--stream和reduce

[java]代码库

package s0224Stream.reduce测试;

import java.util.HashSet;
import java.util.Set;

public class Main {

	public static void main(String[] args) {


//		这种向集合中添加元素的方式学习一下
		Set<String> set=new HashSet<String>(){{ add("张三");add("王五");add("李四");}};

		String t=set.stream().reduce("", (s,e)->s+=" "+e);
		//reduce(identity,accumulator) identity是字符串起始字串,后面是累加操作
		System.out.println(t);
		
		String t2=set.stream().reduce("q", (s,e)->s+=e);
		//reduce(identity,accumulator) identity是字符串起始字串,后面是累加操作
		System.out.println(t2);

	}

}