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

Class AtomicBoolean

public class AtomicBoolean extends Object implements Serializable

A {@code boolean} 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 {@code AtomicBoolean} is used in applications such as atomically updated flags, and cannot be used as a replacement for a java.lang.Boolean.

Since: 1.5

Author: Doug Lea

Constructor Summary
AtomicBoolean(boolean initialValue)
Creates a new {@code AtomicBoolean} with the given initial value.
AtomicBoolean()
Creates a new {@code AtomicBoolean} with initial value {@code false}.
Method Summary
booleancompareAndSet(boolean expect, boolean update)
Atomically sets the value to the given updated value if the current value {@code ==} the expected value.
booleanget()
Returns the current value.
booleangetAndSet(boolean newValue)
Atomically sets to the given value and returns the previous value.
voidlazySet(boolean newValue)
Eventually sets to the given value.
voidset(boolean newValue)
Unconditionally sets to the given value.
StringtoString()
Returns the String representation of the current value.
booleanweakCompareAndSet(boolean expect, boolean update)
Atomically sets the value to the given updated value if the current value {@code ==} the expected value.

Constructor Detail

AtomicBoolean

public AtomicBoolean(boolean initialValue)
Creates a new {@code AtomicBoolean} with the given initial value.

Parameters: initialValue the initial value

AtomicBoolean

public AtomicBoolean()
Creates a new {@code AtomicBoolean} with initial value {@code false}.

Method Detail

compareAndSet

public final boolean compareAndSet(boolean expect, boolean update)
Atomically sets the value to the given updated value if the current value {@code ==} 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.

get

public final boolean get()
Returns the current value.

Returns: the current value

getAndSet

public final boolean getAndSet(boolean newValue)
Atomically sets to the given value and returns the previous value.

Parameters: newValue the new value

Returns: the previous value

lazySet

public final void lazySet(boolean newValue)
Eventually sets to the given value.

Parameters: newValue the new value

Since: 1.6

set

public final void set(boolean newValue)
Unconditionally sets to the given value.

Parameters: newValue the new value

toString

public String toString()
Returns the String representation of the current value.

Returns: the String representation of the current value.

weakCompareAndSet

public boolean weakCompareAndSet(boolean expect, boolean update)
Atomically sets the value to the given updated value if the current value {@code ==} the expected value.

May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to {@code compareAndSet}.

Parameters: expect the expected value update the new value

Returns: true if successful.