edu.emory.mathcs.backport.java.util.concurrent.atomic
Class AtomicInteger

java.lang.Object
  java.lang.Number
      edu.emory.mathcs.backport.java.util.concurrent.atomic.AtomicInteger

All Implemented Interfaces:

java.io.Serializable

public class AtomicInteger

extends java.lang.Number

implements java.io.Serializable

An value that may be updated atomically. See the edu.emory.mathcs.backport.java.util.concurrent.atomic package specification for description of the properties of atomic variables. An is used in applications such as atomically incremented counters, and cannot be used as a replacement for an Integer. However, this class does extend to allow uniform access by tools and utilities that deal with numerically-based classes.

Since:

1.5

Author:

Doug Lea

See Also:

Serialized Form

Constructor Summary

AtomicInteger()
Creates a new AtomicInteger with initial value .

AtomicInteger(int initialValue)
Creates a new AtomicInteger with the given initial value.

Method Summary

int	addAndGet(int delta) Atomically adds the given value to the current value.
boolean	compareAndSet(int expect, int update) Atomically sets the value to the given updated value if the current value the expected value.
int	decrementAndGet() Atomically decrements by one the current value.
double	doubleValue()
float	floatValue()
int	get() Gets the current value.
int	getAndAdd(int delta) Atomically adds the given value to the current value.
int	getAndDecrement() Atomically decrements by one the current value.
int	getAndIncrement() Atomically increments by one the current value.
int	getAndSet(int newValue) Atomically sets to the given value and returns the old value.
int	incrementAndGet() Atomically increments by one the current value.
int	intValue()
void	lazySet(int newValue) Eventually sets to the given value.
long	longValue()
void	set(int newValue) Sets to the given value.
java.lang.String	toString() Returns the String representation of the current value.
boolean	weakCompareAndSet(int expect, int update) Atomically sets the value to the given updated value if the current value the expected value.

Methods inherited from class java.lang.Number

byteValue, shortValue

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

AtomicInteger

public AtomicInteger(int initialValue)

Creates a new AtomicInteger with the given initial value.

Parameters:

initialValue - the initial value

AtomicInteger

public AtomicInteger()

Creates a new AtomicInteger with initial value .

Method Detail

get

public final int get()

Gets the current value.

Returns:

the current value

set

public final void set(int newValue)

Sets to the given value.

Parameters:

newValue - the new value

lazySet

public final void lazySet(int newValue)

Eventually sets to the given value.

Parameters:

newValue - the new value

Since:

1.6

getAndSet

public final int getAndSet(int newValue)

Atomically sets to the given value and returns the old value.

Parameters:

newValue - the new value

Returns:

the previous value

compareAndSet

public final boolean compareAndSet(int expect,
                                   int update)

Atomically sets the value to the given updated value if the current value the expected value.

Parameters:

expect - the expected value

update - the new value

Returns:

true if successful. False return indicates that the actual value was not equal to the expected value.

weakCompareAndSet

public final boolean weakCompareAndSet(int expect,
                                       int update)

Atomically sets the value to the given updated value if the current value the expected value.

May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to .

Parameters:

expect - the expected value

update - the new value

Returns:

true if successful.

getAndIncrement

public final int getAndIncrement()

Atomically increments by one the current value.

Returns:

the previous value

getAndDecrement

public final int getAndDecrement()

Atomically decrements by one the current value.

Returns:

the previous value

getAndAdd

public final int getAndAdd(int delta)

Atomically adds the given value to the current value.

Parameters:

delta - the value to add

Returns:

the previous value

incrementAndGet

public final int incrementAndGet()

Atomically increments by one the current value.

Returns:

the updated value

decrementAndGet

public final int decrementAndGet()

Atomically decrements by one the current value.

Returns:

the updated value

addAndGet

public final int addAndGet(int delta)

Atomically adds the given value to the current value.

Parameters:

delta - the value to add

Returns:

the updated value

toString

public java.lang.String toString()

Returns the String representation of the current value.

Returns:

the String representation of the current value.

intValue

public int intValue()

longValue

public long longValue()

floatValue

public float floatValue()

doubleValue

public double doubleValue()