users.stream().forEach(
item -> System.out.println(item.getId())
);
Optional optional = users.stream().filter(
item -> item.getId().equals("1")
).findFirst();
//提取对象属性为list
Set papiIds = queueList.stream().map(QueueEntity::getItemId).collect(Collectors.toSet());
//过滤
List collect= users.stream().filter(
item -> item.getId().equals("1")
).collect(Collectors.toList());
Set newUris = list.stream().filter(m -> {
String flags = m.get("flags");
if (!m.isEmpty() && !flags.contains("disconnected") && !flags.contains("s_down")) {
return true;
}
return false;
}).map(m -> {
String ip = m.get("ip");
String port = m.get("port");
return convert(ip, port);
}).collect(Collectors.toSet());
//分组
Map> collect = users.stream().collect(
Collectors.groupingBy(c -> c.getSex())
);
//排序
users.sort((User o1, User o2) -> o1.getAge().compareTo(o2.getAge()));
//list -> string
String appCodes = packageList.stream().map(item -> item.getCode()).collect(Collectors.joining(","));
//list -> map
Map userMap= users.stream().collect(
Collectors.toMap((key -> key.getId()), (value -> value))
);
Map propMap = users.stream().collect(
Collectors.toMap(User::getId, User::getName)
);
//map reduce
Optional reduce = users.stream().map(User::getAge).reduce((i, j) -> i + j);
//去重
String[] words = new String[]{"Hello","World"};
List a = Arrays.stream(words)
.map(word -> word.split(""))
.flatMap(Arrays::stream)
.distinct()
.collect(toList());
a.forEach(System.out::print);
转播
