public class

AtomicLong

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

Class Overview

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

Summary

Public Constructors
AtomicLong(long initialValue)
Creates a new AtomicLong with the given initial value.
AtomicLong()
Creates a new AtomicLong with initial value 0.
Public Methods
final long addAndGet(long delta)
Atomically adds the given value to the current value.
final boolean compareAndSet(long expect, long update)
Atomically sets the value to the given updated value if the current value == the expected value.
final long decrementAndGet()
Atomically decrements by one the current value.
double doubleValue()
Returns the value of the specified number as a double.
float floatValue()
Returns the value of the specified number as a float.
final long get()
Gets the current value.
final long getAndAdd(long delta)
Atomically adds the given value to the current value.
final long getAndDecrement()
Atomically decrements by one the current value.
final long getAndIncrement()
Atomically increments by one the current value.
final long getAndSet(long newValue)
Atomically sets to the given value and returns the old value.
final long incrementAndGet()
Atomically increments by one the current value.
int intValue()
Returns the value of the specified number as an int.
final void lazySet(long newValue)
Eventually sets to the given value.
long longValue()
Returns the value of the specified number as a long.
final void set(long newValue)
Sets to the given value.
String toString()
Returns the String representation of the current value.
final boolean weakCompareAndSet(long expect, long 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 AtomicLong (long initialValue)

Creates a new AtomicLong with the given initial value.

Parameters
initialValue the initial value

public AtomicLong ()

Creates a new AtomicLong with initial value 0.

Public Methods

public final long addAndGet (long delta)

Atomically adds the given value to the current value.

Parameters
delta the value to add
Returns
  • the updated value

public final boolean compareAndSet (long expect, long 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.

public final long decrementAndGet ()

Atomically decrements by one the current value.

Returns
  • the updated value

public double doubleValue ()

Returns the value of the specified number as a double. This may involve rounding.

Returns
  • the numeric value represented by this object after conversion to type double.

public float floatValue ()

Returns the value of the specified number as a float. This may involve rounding.

Returns
  • the numeric value represented by this object after conversion to type float.

public final long get ()

Gets the current value.

Returns
  • the current value

public final long getAndAdd (long delta)

Atomically adds the given value to the current value.

Parameters
delta the value to add
Returns
  • the previous value

public final long getAndDecrement ()

Atomically decrements by one the current value.

Returns
  • the previous value

public final long getAndIncrement ()

Atomically increments by one the current value.

Returns
  • the previous value

public final long getAndSet (long newValue)

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

Parameters
newValue the new value
Returns
  • the previous value

public final long incrementAndGet ()

Atomically increments by one the current value.

Returns
  • the updated value

public int intValue ()

Returns the value of the specified number as an int. This may involve rounding or truncation.

Returns
  • the numeric value represented by this object after conversion to type int.

public final void lazySet (long newValue)

Eventually sets to the given value.

Parameters
newValue the new value

public long longValue ()

Returns the value of the specified number as a long. This may involve rounding or truncation.

Returns
  • the numeric value represented by this object after conversion to type long.

public final void set (long newValue)

Sets to the given value.

Parameters
newValue the new value

public String toString ()

Returns the String representation of the current value.

Returns
  • the String representation of the current value.

public final boolean weakCompareAndSet (long expect, long 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 compareAndSet.

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