QWriteLocker Class
The QWriteLocker class is a convenience class that simplifies locking and unlocking read-write locks for write access. More...
Header: | #include <QWriteLocker> |
qmake: | QT += core |
Note: All functions in this class are thread-safe.
Public Functions
QWriteLocker(QReadWriteLock *readWriteLock) | |
~QWriteLocker() | |
QReadWriteLock * | readWriteLock() const |
void | relock() |
void | unlock() |
Detailed Description
The QWriteLocker class is a convenience class that simplifies locking and unlocking read-write locks for write access.
The purpose of QWriteLocker (and QReadLocker) is to simplify QReadWriteLock locking and unlocking. Locking and unlocking statements or in exception handling code is error-prone and difficult to debug. QWriteLocker can be used in such situations to ensure that the state of the lock is always well-defined.
Here's an example that uses QWriteLocker to lock and unlock a read-write lock for writing:
QReadWriteLock lock; void writeData(const QByteArray &data) { QWriteLocker locker(&lock); ... }
It is equivalent to the following code:
QReadWriteLock lock; void writeData(const QByteArray &data) { lock.lockForWrite(); ... lock.unlock(); }
The QMutexLocker documentation shows examples where the use of a locker object greatly simplifies programming.
See also QReadLocker and QReadWriteLock.
Member Function Documentation
QWriteLocker::QWriteLocker(QReadWriteLock *readWriteLock)
Default constructs an instance of QWriteLocker.
QWriteLocker::~QWriteLocker()
Destroys the instance of QWriteLocker.