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## java.util.concurrent.atomic
Class AtomicBoolean

    java.lang.Object
      java.util.concurrent.atomic.AtomicBoolean

All Implemented Interfaces:
  Serializable

    public class AtomicBoolean

extends Object
implements Serializable

A `boolean` value that may be updated atomically. See the `java.util.concurrent.atomic` package specification for description of the properties of atomic variables. An `AtomicBoolean` is used in applications such as atomically updated flags, and cannot be used as a replacement for a `Boolean`.

Since:
  1.5
See Also:
  Serialized Form

Constructor Summary
`AtomicBoolean()` Creates a new `AtomicBoolean` with initial value `false`.
`AtomicBoolean(boolean initialValue)` Creates a new `AtomicBoolean` with the given initial value.

Method Summary
`boolean` | `compareAndSet(boolean expect, boolean update)` Atomically sets the value to the given updated value if the current value `==` the expected value.
`boolean` | `get()` Returns the current value.
`boolean` | `getAndSet(boolean newValue)` Atomically sets to the given value and returns the previous value.
`void` | `lazySet(boolean newValue)` Eventually sets to the given value.
`void` | `set(boolean newValue)` Unconditionally sets to the given value.
`String` | `toString()` Returns the String representation of the current value.
`boolean` | `weakCompareAndSet(boolean expect, boolean update)` Atomically sets the value to the given updated value if the current value `==` the expected value.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Constructor Detail

### AtomicBoolean

    public AtomicBoolean(boolean initialValue)

  Creates a new `AtomicBoolean` with the given initial value.

  Parameters:
    `initialValue` - the initial value

### AtomicBoolean

    public AtomicBoolean()

  Creates a new `AtomicBoolean` with initial value `false`.

Method Detail

### get

    public final boolean get()

  Returns the current value.

  Returns:
    the current value

### compareAndSet

    public final boolean compareAndSet(boolean expect,
                                       boolean 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 boolean weakCompareAndSet(boolean expect,
                                     boolean 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.

### set

    public final void set(boolean newValue)

  Unconditionally sets to the given value.

  Parameters:
    `newValue` - the new value

### lazySet

    public final void lazySet(boolean newValue)

  Eventually sets to the given value.

  Parameters:
    `newValue` - the new value
  Since:
    1.6

### 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

### toString

    public String toString()

  Returns the String representation of the current value.

  Overrides:
    `toString` in class `Object`
  Returns:
    the String representation of the current value.

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For further API reference and developer documentation, see Java SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

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