我正在使用use std::collections::{HashMap, HashSet};
use std::hash::Hash;
pub trait Point2: Eq + Hash {}
pub trait Link2<'a, A, B>: Eq + Hash {
fn origin(&self, x: i8) -> Option<&'a A>;
fn set_origin(&mut self, x: i8, o: A);
fn target(&self, x: i8) -> Option<&'a B>;
fn set_target(&mut self, x: i8, t: B);
}
pub struct Web<'a, V, E>
where
V: Point2,
E: Link2<'a, V, V>,
{
map: HashSet<(V, E, V)>,
inc: HashMap<&'a V, HashSet<&'a E>>,
}
impl<'a, V, E> Web<'a, V, E>
where
V: Point2,
E: Link2<'a, V, V>,
{
pub fn new(map: HashSet<(V, E, V)>) -> Self {
let mut y = Self {
map,
inc: HashMap::new(),
};
for x in &(y).map {
if let Some(val) = y.inc.get_mut(&x.2) {
val.insert(&x.1);
} else {
let mut z = HashSet::new();
&z.insert(&x.1);
y.inc.insert(&x.2, z);
}
}
y
}
}
库来请求文件信息，如下所示：
error[E0515]: cannot return value referencing local data `y.map`
--> src/lib.rs:43:9
|
33 | for x in &(y).map {
| -------- `y.map` is borrowed here
...
43 | y
| ^ returns a value referencing data owned by the current function
error[E0505]: cannot move out of `y` because it is borrowed
--> src/lib.rs:43:9
|
22 | impl<'a, V, E> Web<'a, V, E>
| -- lifetime `'a` defined here
...
33 | for x in &(y).map {
| -------- borrow of `y.map` occurs here
...
43 | y
| ^
| |
| move out of `y` occurs here
| returning this value requires that `y.map` is borrowed for `'a`
要取消请求，我使用此代码，如this所说：
OKHttp但是 final String url = "my_url";
final String tag = "tag";
final OkHttpClient client = new OkHttpClient();
Thread t = new Thread(new Runnable() {
@Override
public void run() {
try {
Request request = new Request.Builder()
.url(url)
.get()
.tag(tag)
.build();
Call call = client.newCall(request);
Response response = call.execute();
//work with response object, etc.
} catch (IOException e) {
System.out.println("Error: " + e.toString());
}
}
});
t.start();
列表和 for (Call call : mHttpClient.dispatcher().queuedCalls()) {
if (call.request().tag().equals("tag"))
call.cancel();
}
for (Call call : mHttpClient.dispatcher().runningCalls()) {
if (call.request().tag().equals("tag"))
call.cancel();
}
列表的大小为零。为什么？如何在OKHttp中取消请求？谢谢。