class Poco::AtomicCounter

Overview

This class implements a simple counter, which provides atomic operations that are safe to use in a multithreaded environment. More…

#include <AtomicCounter.h>

class AtomicCounter
{
public:
    // typedefs

    typedef int ValueType;

    // construction

    AtomicCounter();
    AtomicCounter(ValueType initialValue);
    AtomicCounter(const AtomicCounter& counter);

    // methods

    AtomicCounter&
    operator=(const AtomicCounter& counter);

    AtomicCounter&
    operator=(ValueType value);

    operator ValueType() const;

    ValueType
    value() const;

    ValueType
    operator++();

    ValueType
    operator++(int);

    ValueType
    operator--();

    ValueType
    operator--(int);

    bool
    operator!() const;
};

Detailed Documentation

This class implements a simple counter, which provides atomic operations that are safe to use in a multithreaded environment.

Typical usage of AtomicCounter is for implementing reference counting and similar things.

On some platforms, the implementation of AtomicCounter is based on atomic primitives specific to the platform (such as InterlockedIncrement, etc. on Windows), and thus very efficient. On platforms that do not support atomic primitives, operations are guarded by a FastMutex.

The following platforms currently have atomic primitives:

- Windows
- Mac OS X
- GCC 4.1+ (Intel platforms only)

Typedefs

typedef int ValueType

The underlying integer type.

Construction

AtomicCounter()

Creates a new AtomicCounter and initializes it to zero.

AtomicCounter(ValueType initialValue)

Creates a new AtomicCounter and initializes it with the given value.

AtomicCounter(const AtomicCounter& counter)

Creates the counter by copying another one.

Methods

AtomicCounter&
operator=(const AtomicCounter& counter)

Assigns the value of another AtomicCounter.

AtomicCounter&
operator=(ValueType value)

Assigns a value to the counter.

operator ValueType() const

Returns the value of the counter.

ValueType
value() const

Returns the value of the counter.

ValueType
operator++()

Increments the counter and returns the result.

ValueType
operator++(int)

Increments the counter and returns the previous value.

ValueType
operator--()

Decrements the counter and returns the result.

ValueType
operator--(int)

Decrements the counter and returns the previous value.

bool
operator!() const

Returns true if the counter is zero, false otherwise.