代码语言：javascript复制
public class TempUser {
private final ConcurrentHashMap<String, Future<String>> cache = new ConcurrentHashMap<>();
private final ConcurrentHashMap<String, FutureTask<String>> taskCache = new ConcurrentHashMap<>();
public String setUser(String name, String content) {
while (true) {
Future<String> f = cache.get(name);
if (f == null) {
Callable<String> callable = new Callable<String>() {
@Override
public String call() throws Exception {
return content;
}
};
FutureTask<String> ft = new FutureTask<String>(callable);
Future<String> stringFuture = cache.putIfAbsent(name, ft);
//如果放入成功 返回null
if(stringFuture==null){
f = ft;
ft.run();
}
try {
return f.get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
}
}
public int getSize(){
return cache.size();
}
public String setUser02(String name, String content) {
while (true) {
FutureTask<String> ft = taskCache.get(name);
if (ft == null) {
Callable<String> callable = new Callable<String>() {
@Override
public String call() throws Exception {
return content;
}
};
FutureTask<String> ft2 = new FutureTask<String>(callable);
Future<String> stringFuture = cache.putIfAbsent(name, ft2);
//如果放入成功 返回null
if(stringFuture==null){
ft = ft2;
ft2.run();
}
try {
return ft.get();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (ExecutionException e) {
e.printStackTrace();
}
}
}
}
}
