Stream流式處理：
建立在Lambda表達(dá)式基礎(chǔ)上的多數(shù)據(jù)處理技術(shù)。
可以對(duì)集合進(jìn)行迭代、去重、篩選、排序、聚合等處理，極大的簡(jiǎn)化了代碼量。

Stream常用方法

Stream流對(duì)象的五種創(chuàng)建方式

//基于數(shù)組
String[] arr = {"a","b","c"};
Stream<String> stream = Stream.of(arr);
stream.forEach(s->System.out.println(s));
//基于集合
List<String> list = new ArrayList<>();
list.add("a");
list.add("b");
list.add("c");
Stream<String> stream = list.stream();//list中的stream()方法
stream.forEach(s->System.out.println(s));
//利用generate方法創(chuàng)建無限長(zhǎng)度流
Stream<Integer> stream = Stream.generate(()->new Random().nextInt(100000));
stream.forEach(i->System.out.println(i));
stream.limit(10).forEach(i->System.out.println(i));//限制長(zhǎng)度為10
//基于迭代器創(chuàng)建流
Stream<Integer> stream = Stream.iterate(1,n->n+1);//數(shù)據(jù)起始值，步長(zhǎng)(生成無限長(zhǎng))
//基于字符序列創(chuàng)建流
String str = "abcdefg";
IntStream stream = str.chars();
stream.forEach(c->System.out.println((char)c));