AtomicInteger (Java Platform SE 8 ) (original) (raw)

java.lang.Object
- java.lang.Number
- - java.util.concurrent.atomic.AtomicInteger
All Implemented Interfaces:
Serializable

public class AtomicInteger
extends Number
implements Serializable
An int value that may be updated atomically. See thejava.util.concurrent.atomic package specification for description of the properties of atomic variables. AnAtomicInteger is used in applications such as atomically incremented counters, and cannot be used as a replacement for anInteger. However, this class does extendNumber to allow uniform access by tools and utilities that deal with numerically-based classes.
Since:
1.5
See Also:
Serialized Form

Constructor Summary

Constructors

Constructor	Description
AtomicInteger()	Creates a new AtomicInteger with initial value 0.
AtomicInteger(int initialValue)	Creates a new AtomicInteger with the given initial value.

Method Summary

All Methods Instance Methods Concrete Methods

Modifier and Type	Method	Description
int	accumulateAndGet(int x,IntBinaryOperator accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value.
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()	Returns the value of this AtomicInteger as a double after a widening primitive conversion.
float	floatValue()	Returns the value of this AtomicInteger as a float after a widening primitive conversion.
int	get()	Gets the current value.
int	getAndAccumulate(int x,IntBinaryOperator accumulatorFunction)	Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous 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	getAndUpdate(IntUnaryOperator updateFunction)	Atomically updates the current value with the results of applying the given function, returning the previous value.
int	incrementAndGet()	Atomically increments by one the current value.
int	intValue()	Returns the value of this AtomicInteger as an int.
void	lazySet(int newValue)	Eventually sets to the given value.
long	longValue()	Returns the value of this AtomicInteger as a long after a widening primitive conversion.
void	set(int newValue)	Sets to the given value.
String	toString()	Returns the String representation of the current value.
int	updateAndGet(IntUnaryOperator updateFunction)	Atomically updates the current value with the results of applying the given function, returning the updated 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](../../../../java/lang/Number.html "class in java.lang")  
   `[byteValue](../../../../java/lang/Number.html#byteValue--), [shortValue](../../../../java/lang/Number.html#shortValue--)`  
   * ### Methods inherited from class java.lang.[Object](../../../../java/lang/Object.html "class in java.lang")  
   `[clone](../../../../java/lang/Object.html#clone--), [equals](../../../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../../../java/lang/Object.html#finalize--), [getClass](../../../../java/lang/Object.html#getClass--), [hashCode](../../../../java/lang/Object.html#hashCode--), [notify](../../../../java/lang/Object.html#notify--), [notifyAll](../../../../java/lang/Object.html#notifyAll--), [wait](../../../../java/lang/Object.html#wait--), [wait](../../../../java/lang/Object.html#wait-long-), [wait](../../../../java/lang/Object.html#wait-long-int-)`

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 `0`.

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)  
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  
* #### getAndUpdate  
public final int getAndUpdate([IntUnaryOperator](../../../../java/util/function/IntUnaryOperator.html "interface in java.util.function") updateFunction)  
Atomically updates the current value with the results of applying the given function, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.  
Parameters:  
`updateFunction` \- a side-effect-free function  
Returns:  
the previous value  
Since:  
1.8  
* #### updateAndGet  
public final int updateAndGet([IntUnaryOperator](../../../../java/util/function/IntUnaryOperator.html "interface in java.util.function") updateFunction)  
Atomically updates the current value with the results of applying the given function, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads.  
Parameters:  
`updateFunction` \- a side-effect-free function  
Returns:  
the updated value  
Since:  
1.8  
* #### getAndAccumulate  
public final int getAndAccumulate(int x,  
                                  [IntBinaryOperator](../../../../java/util/function/IntBinaryOperator.html "interface in java.util.function") accumulatorFunction)  
Atomically updates the current value with the results of applying the given function to the current and given values, returning the previous value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.  
Parameters:  
`x` \- the update value  
`accumulatorFunction` \- a side-effect-free function of two arguments  
Returns:  
the previous value  
Since:  
1.8  
* #### accumulateAndGet  
public final int accumulateAndGet(int x,  
                                  [IntBinaryOperator](../../../../java/util/function/IntBinaryOperator.html "interface in java.util.function") accumulatorFunction)  
Atomically updates the current value with the results of applying the given function to the current and given values, returning the updated value. The function should be side-effect-free, since it may be re-applied when attempted updates fail due to contention among threads. The function is applied with the current value as its first argument, and the given update as the second argument.  
Parameters:  
`x` \- the update value  
`accumulatorFunction` \- a side-effect-free function of two arguments  
Returns:  
the updated value  
Since:  
1.8  
* #### toString  
public [String](../../../../java/lang/String.html "class in java.lang") toString()  
Returns the String representation of the current value.  
Overrides:  
`[toString](../../../../java/lang/Object.html#toString--)` in class `[Object](../../../../java/lang/Object.html "class in java.lang")`  
Returns:  
the String representation of the current value  
* #### intValue  
public int intValue()  
Returns the value of this `AtomicInteger` as an `int`.  
Specified by:  
`[intValue](../../../../java/lang/Number.html#intValue--)` in class `[Number](../../../../java/lang/Number.html "class in java.lang")`  
Returns:  
the numeric value represented by this object after conversion to type `int`.  
* #### longValue  
public long longValue()  
Returns the value of this `AtomicInteger` as a `long` after a widening primitive conversion.  
Specified by:  
`[longValue](../../../../java/lang/Number.html#longValue--)` in class `[Number](../../../../java/lang/Number.html "class in java.lang")`  
Returns:  
the numeric value represented by this object after conversion to type `long`.  
See  The Java™ Language Specification:  
5.1.2 Widening Primitive Conversions  
* #### floatValue  
public float floatValue()  
Returns the value of this `AtomicInteger` as a `float` after a widening primitive conversion.  
Specified by:  
`[floatValue](../../../../java/lang/Number.html#floatValue--)` in class `[Number](../../../../java/lang/Number.html "class in java.lang")`  
Returns:  
the numeric value represented by this object after conversion to type `float`.  
See  The Java™ Language Specification:  
5.1.2 Widening Primitive Conversions  
* #### doubleValue  
public double doubleValue()  
Returns the value of this `AtomicInteger` as a `double` after a widening primitive conversion.  
Specified by:  
`[doubleValue](../../../../java/lang/Number.html#doubleValue--)` in class `[Number](../../../../java/lang/Number.html "class in java.lang")`  
Returns:  
the numeric value represented by this object after conversion to type `double`.  
See  The Java™ Language Specification:  
5.1.2 Widening Primitive Conversions

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AtomicInteger (Java Platform SE 8 ) (original) (raw)

Constructor Summary

Method Summary

Constructor Detail

Method Detail