Java8 流处理

记录Java8流处理

/*
*author:cst
*如有错误请指出
*/

FlatMap()

Stream.flatMap(Function> mapper)

api:
Returns a stream consisting of the results of replacing each element of this stream with the contents of a mapped stream produced by applying the provided mapping function to each element. Each mapped stream is closed after its contents have been placed into this stream. (If a mapped stream is null an empty stream is used, instead.) 

返回一个流，原先流的每个原始被指定函数返回的流里所有元素替换。每一个返回的新流在替换进原先流的元素之后将关闭。（如果返回的流是null，那个将会使用一个空流来替代）

如：
List list = Arrays.asList(3,5,6,9,23,69,6,3,8,63);

Stream s = list.stream().flatMap(e->filteInteger(e));
s.forEach(e->System.out.println(e));

private static Stream filteInteger(Integer i)
	{
		List l = new LinkedList();
		if(i.intValue()>10)
		{
			l.add(1);l.add(2);
		}
		return l.stream();
	}
	
//将会输出
1
2
1
2
1
2