IT. Expert System.

Enclosing class:

PowerManager

public final class PowerManager.WakeLock
extends Object

• Method Summary

  Methods

  Modifier and Type	Method and Description
  void	acquire() Acquires the wake lock.
  void	acquire(long timeout) Acquires the wake lock with a timeout.
  protected void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
  boolean	isHeld() Returns true if the wake lock has been acquired but not yet released.
  void	release() Releases the wake lock.
  void	release(int flags) Releases the wake lock with flags to modify the release behavior.
  void	setReferenceCounted(boolean value) Sets whether this WakeLock is reference counted.
  void	setWorkSource(WorkSource ws) Sets the work source associated with the wake lock.
  String	toString() Returns a string containing a concise, human-readable description of this object.

  • Methods inherited from class java.lang.Object

    clone, equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

• Method Detail

  • finalize

    protected void finalize()
                     throws Throwable

    Description copied from class: Object
    Invoked when the garbage collector has detected that this instance is no longer reachable. The default implementation does nothing, but this method can be overridden to free resources.

    Note that objects that override finalize are significantly more expensive than objects that don't. Finalizers may be run a long time after the object is no longer reachable, depending on memory pressure, so it's a bad idea to rely on them for cleanup. Note also that finalizers are run on a single VM-wide finalizer thread, so doing blocking work in a finalizer is a bad idea. A finalizer is usually only necessary for a class that has a native peer and needs to call a native method to destroy that peer. Even then, it's better to provide an explicit close method (and implement Closeable), and insist that callers manually dispose of instances. This works well for something like files, but less well for something like a BigInteger where typical calling code would have to deal with lots of temporaries. Unfortunately, code that creates lots of temporaries is the worst kind of code from the point of view of the single finalizer thread.

    If you must use finalizers, consider at least providing your own ReferenceQueue and having your own thread process that queue.

    Unlike constructors, finalizers are not automatically chained. You are responsible for calling super.finalize() yourself.

    Uncaught exceptions thrown by finalizers are ignored and do not terminate the finalizer thread. See Effective Java Item 7, "Avoid finalizers" for more.

    Overrides:

    finalize in class Object

    Throws:

    Throwable

  • setReferenceCounted

    public void setReferenceCounted(boolean value)

    Sets whether this WakeLock is reference counted.

    Wake locks are reference counted by default. If a wake lock is reference counted, then each call to acquire() must be balanced by an equal number of calls to release(). If a wake lock is not reference counted, then one call to release() is sufficient to undo the effect of all previous calls to acquire().

    Parameters:

    value - True to make the wake lock reference counted, false to make the wake lock non-reference counted.

  • acquire

    public void acquire()

    Acquires the wake lock.

    Ensures that the device is on at the level requested when the wake lock was created.

  • acquire

    public void acquire(long timeout)

    Acquires the wake lock with a timeout.

    Ensures that the device is on at the level requested when the wake lock was created. The lock will be released after the given timeout expires.

    Parameters:

    timeout - The timeout after which to release the wake lock, in milliseconds.

  • release

    public void release()

    Releases the wake lock.

    This method releases your claim to the CPU or screen being on. The screen may turn off shortly after you release the wake lock, or it may not if there are other wake locks still held.

  • release

    public void release(int flags)

    Releases the wake lock with flags to modify the release behavior.

    This method releases your claim to the CPU or screen being on. The screen may turn off shortly after you release the wake lock, or it may not if there are other wake locks still held.

    Parameters:

    flags - Combination of flag values to modify the release behavior. Currently only PowerManager.WAIT_FOR_PROXIMITY_NEGATIVE is supported.

  • isHeld

    public boolean isHeld()

    Returns true if the wake lock has been acquired but not yet released.

    Returns:

    True if the wake lock is held.

  • setWorkSource

    public void setWorkSource(WorkSource ws)

    Sets the work source associated with the wake lock.

    The work source is used to determine on behalf of which application the wake lock is being held. This is useful in the case where a service is performing work on behalf of an application so that the cost of that work can be accounted to the application.

    Parameters:

    ws - The work source, or null if none.

  • toString

    public String toString()

    Description copied from class: Object
    Returns a string containing a concise, human-readable description of this object. Subclasses are encouraged to override this method and provide an implementation that takes into account the object's type and data. The default implementation is equivalent to the following expression:

       getClass().getName() + '@' + Integer.toHexString(hashCode())

    See Writing a useful toString method if you intend implementing your own toString method.

    Overrides:

    toString in class Object

    Returns:

    a printable representation of this object.