java8 Stream map()

在java8中 Stream.map()可以将对象收集起来，组成新的流,首先看看源码，再看例子吧。

------- 字符串转大写

package com.Cz.smile;import java.util.ArrayList;import java.util.Arrays;import java.util.List;import java.util.stream.Collectors;public class Java8Demo {    public static void main(String[] args) {        List<String> list= Arrays.asList("a","b","c","d","e");        //java8 以前        List<String> result=new ArrayList<>();        for(String stream : list){            result.add(stream.toUpperCase());        }        for (String str: result) {            System.out.print(str);        }        //Java8        list.stream().map(e->e.toUpperCase()).collect(Collectors.toList()).forEach(System.out::print);    }}