public class

AtomicInteger

extends Number
implements Serializable
java.lang.Object
   ↳ java.lang.Number
     ↳ java.util.concurrent.atomic.AtomicInteger

Class Overview

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

Summary

Public Constructors
AtomicInteger(int initialValue)
Creates a new AtomicInteger with the given initial value.
AtomicInteger()
Creates a new AtomicInteger with initial value 0.
Public Methods
final int addAndGet(int delta)
Atomically adds the given value to the current value.
final boolean compareAndSet(int expect, int update)
Atomically sets the value to the given updated value if the current value == the expected value.
final int decrementAndGet()
Atomically decrements by one the current value.
double doubleValue()
Returns this object's value as a double.
float floatValue()
Returns this object's value as a float.
final int get()
Gets the current value.
final int getAndAdd(int delta)
Atomically adds the given value to the current value.
final int getAndDecrement()
Atomically decrements by one the current value.
final int getAndIncrement()
Atomically increments by one the current value.
final int getAndSet(int newValue)
Atomically sets to the given value and returns the old value.
final int incrementAndGet()
Atomically increments by one the current value.
int intValue()
Returns this object's value as an int.
final void lazySet(int newValue)
Eventually sets to the given value.
long longValue()
Returns this object's value as a long.
final void set(int newValue)
Sets to the given value.
String toString()
Returns the String representation of the current value.
final boolean weakCompareAndSet(int expect, int update)
Atomically sets the value to the given updated value if the current value == the expected value.
[Expand]
Inherited Methods
From class java.lang.Number
From class java.lang.Object

Public Constructors

public AtomicInteger (int initialValue)

Since: API Level 1

Creates a new AtomicInteger with the given initial value.

Parameters
initialValue the initial value

public AtomicInteger ()

Since: API Level 1

Creates a new AtomicInteger with initial value 0.

Public Methods

public final int addAndGet (int delta)

Since: API Level 1

Atomically adds the given value to the current value.

Parameters
delta the value to add
Returns
  • the updated value

public final boolean compareAndSet (int expect, int update)

Since: API Level 1

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.

public final int decrementAndGet ()

Since: API Level 1

Atomically decrements by one the current value.

Returns
  • the updated value

public double doubleValue ()

Since: API Level 1

Returns this object's value as a double. Might involve rounding.

Returns
  • the primitive double value of this object.

public float floatValue ()

Since: API Level 1

Returns this object's value as a float. Might involve rounding.

Returns
  • the primitive float value of this object.

public final int get ()

Since: API Level 1

Gets the current value.

Returns
  • the current value

public final int getAndAdd (int delta)

Since: API Level 1

Atomically adds the given value to the current value.

Parameters
delta the value to add
Returns
  • the previous value

public final int getAndDecrement ()

Since: API Level 1

Atomically decrements by one the current value.

Returns
  • the previous value

public final int getAndIncrement ()

Since: API Level 1

Atomically increments by one the current value.

Returns
  • the previous value

public final int getAndSet (int newValue)

Since: API Level 1

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

Parameters
newValue the new value
Returns
  • the previous value

public final int incrementAndGet ()

Since: API Level 1

Atomically increments by one the current value.

Returns
  • the updated value

public int intValue ()

Since: API Level 1

Returns this object's value as an int. Might involve rounding and/or truncating the value, so it fits into an int.

Returns
  • the primitive int value of this object.

public final void lazySet (int newValue)

Since: API Level 9

Eventually sets to the given value.

Parameters
newValue the new value

public long longValue ()

Since: API Level 1

Returns this object's value as a long. Might involve rounding and/or truncating the value, so it fits into a long.

Returns
  • the primitive long value of this object.

public final void set (int newValue)

Since: API Level 1

Sets to the given value.

Parameters
newValue the new value

public String toString ()

Since: API Level 1

Returns the String representation of the current value.

Returns
  • the String representation of the current value.

public final boolean weakCompareAndSet (int expect, int update)

Since: API Level 1

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 compareAndSet.

Parameters
expect the expected value
update the new value
Returns
  • true if successful.