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 this object's value as a double.
float floatValue()
Returns this object's value 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 this object's value as an int.
final void lazySet(long newValue)
Eventually sets to the given value.
long longValue()
Returns this object's value 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)

Since: API Level 1

Creates a new AtomicLong with the given initial value.

Parameters
initialValue the initial value

public AtomicLong ()

Since: API Level 1

Creates a new AtomicLong with initial value 0.

Public Methods

public final long addAndGet (long 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 (long expect, long 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 long 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 long get ()

Since: API Level 1

Gets the current value.

Returns
  • the current value

public final long getAndAdd (long 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 long getAndDecrement ()

Since: API Level 1

Atomically decrements by one the current value.

Returns
  • the previous value

public final long getAndIncrement ()

Since: API Level 1

Atomically increments by one the current value.

Returns
  • the previous value

public final long getAndSet (long 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 long 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 (long 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 (long 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 (long expect, long 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.