1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
|
/*
* Copyright (c) 2013, Ford Motor Company
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following
* disclaimer in the documentation and/or other materials provided with the
* distribution.
*
* Neither the name of the Ford Motor Company nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SRC_COMPONENTS_UTILS_INCLUDE_UTILS_PRIORITIZED_QUEUE_H_
#define SRC_COMPONENTS_UTILS_INCLUDE_UTILS_PRIORITIZED_QUEUE_H_
#include <queue>
#include <map>
#include <iostream>
#include "utils/macro.h"
namespace utils {
/*
* Template queue class that gives out messages respecting their priority
* Message class must have size_t PriorityOrder() method implemented
*/
template < typename M >
class PrioritizedQueue {
public:
typedef M value_type;
// std::map guarantees it's contents is sorted by key
typedef std::map<size_t, std::queue<value_type> > QueuesMap;
PrioritizedQueue()
: total_size_(0) {
}
// All api mimics usual std queue interface
void push(const value_type& message) {
size_t message_priority = message.PriorityOrder();
queues_[message_priority].push(message);
++total_size_;
}
size_t size() const {
return total_size_;
}
bool empty() const {
return queues_.empty();
}
value_type front() {
DCHECK(!queues_.empty() && !queues_.rbegin()->second.empty());
return queues_.rbegin()->second.front();
}
void pop() {
DCHECK(!queues_.empty() && !queues_.rbegin()->second.empty());
typename QueuesMap::iterator last = --queues_.end();
last->second.pop();
--total_size_;
if (last->second.empty()) {
queues_.erase(last);
}
}
private:
QueuesMap queues_;
size_t total_size_;
};
}
#endif // SRC_COMPONENTS_UTILS_INCLUDE_UTILS_
|