1/* -*- C++ -*-
2 This file declares the Collection class.
3
4 SPDX-FileCopyrightText: 2004-2013 Mirko Boehm <mirko@kde.org>
5
6 SPDX-License-Identifier: LGPL-2.0-or-later
7*/
8
9#ifndef JOBCOLLECTION_H
10#define JOBCOLLECTION_H
11
12#include "job.h"
13#include "jobpointer.h"
14#include "lambda.h"
15
16#include <functional>
17
18namespace ThreadWeaver
19{
20class Thread;
21class CollectionExecuteWrapper;
22
23namespace Private
24{
25class Collection_Private;
26}
27
28/** A Collection is a vector of Jobs that will be queued together.
29 * In a Collection, the order of execution of the elements is not specified.
30 *
31 * It is intended that the collection is set up first and then
32 * queued. After queuing, no further jobs should be added to the collection.
33 */
34class THREADWEAVER_EXPORT Collection : public Job
35{
36public:
37 Collection();
38 Collection(ThreadWeaver::Private::Collection_Private *d);
39 ~Collection() override;
40
41 /** Append a job to the collection.
42 *
43 * To use Collection, create the Job objects first, add them to the collection, and then queue it. After
44 * the collection has been queued, no further Jobs are supposed to be added.
45 *
46 * @note Once the job has been added, execute wrappers can no more be set on it */
47 virtual void addJob(JobPointer);
48
49 /** Stop processing, dequeue all remaining Jobs.
50 *
51 * @since 6.0
52 */
53 void stop();
54
55 /** Dequeue all remaining Jobs and request abortion of all running jobs
56 * @see Job::requestAbort()
57 *
58 * @since 6.0
59 */
60 void requestAbort() override;
61
62 /** Return the number of elements in the collection. */
63 int elementCount() const;
64
65 /** @brief Add the job to this collection by pointer. */
66 Collection &operator<<(ThreadWeaver::JobInterface *job);
67
68 /** @brief Add the job to this collection. */
69 Collection &operator<<(const ThreadWeaver::JobPointer &job);
70 Collection &operator<<(JobInterface &job);
71
72protected:
73 /** Overload to queue the collection. */
74 void aboutToBeQueued_locked(QueueAPI *api) override;
75
76 /** Overload to dequeue the collection. */
77 void aboutToBeDequeued_locked(QueueAPI *api) override;
78
79 /** Return a ref-erence to the job in the job list at position i. */
80 JobPointer jobAt(int i);
81
82 // FIXME remove
83 /** Return the number of jobs in the joblist.
84 * Assumes that the mutex is being held.
85 */
86 virtual int jobListLength_locked() const;
87
88protected:
89 /** Overload the execute method. */
90 void execute(const JobPointer &job, Thread *) override;
91
92 /** Overload run().
93 * We have to. */
94 void run(JobPointer self, Thread *thread) override;
95
96protected:
97 friend class CollectionExecuteWrapper; // needs to access d()
98 friend class Collection_Private;
99 ThreadWeaver::Private::Collection_Private *d();
100 const ThreadWeaver::Private::Collection_Private *d() const;
101};
102
103/**
104 * Make a Collection that will execute specified callable (eg. Lambda) for each item in given iterable container
105 * You can use it to have a parallel map function.
106 */
107template<typename Iterable, typename FN>
108QSharedPointer<Collection> make_collection(Iterable iterable, FN callable)
109{
110 QSharedPointer<Collection> collection(new Collection());
111 for (auto it = iterable.begin(); it != iterable.end(); ++it) {
112 *collection << make_job([callable, item = *it, collectionJob = collection.get()]() {
113 callable(item, *collectionJob);
114 });
115 }
116 return collection;
117}
118}
119
120#endif
121

source code of threadweaver/src/collection.h