public class UpdateLock extends Object
Modifier and Type | Field and Description |
---|---|
static String |
NOW_IS_CONVENIENT
Boolean Intent extra on the UPDATE_LOCK_CHANGED sticky broadcast, indicating
whether now is an appropriate time to interrupt device activity with an
update operation.
|
static String |
TIMESTAMP
Long Intent extra on the UPDATE_LOCK_CHANGED sticky broadcast, marking the
wall-clock time [in UTC] at which the broadcast was sent.
|
static String |
UPDATE_LOCK_CHANGED
Broadcast Intent action sent when the global update lock state changes,
i.e. when the first locker acquires an update lock, or when the last
locker releases theirs.
|
Constructor and Description |
---|
UpdateLock(String tag)
Construct an UpdateLock instance.
|
Modifier and Type | Method and Description |
---|---|
void |
acquire()
Acquire an update lock.
|
protected void |
finalize()
Called by the garbage collector on an object when garbage collection
determines that there are no more references to the object.
|
boolean |
isHeld()
Is this lock currently held?
|
void |
release()
Release this update lock.
|
void |
setReferenceCounted(boolean isRefCounted)
Change the refcount behavior of this update lock.
|
public static final String UPDATE_LOCK_CHANGED
public static final String NOW_IS_CONVENIENT
public static final String TIMESTAMP
public UpdateLock(String tag)
tag
- An arbitrary string used to identify this lock instance in dump output.public void setReferenceCounted(boolean isRefCounted)
public boolean isHeld()
public void acquire()
public void release()
protected void finalize() throws Throwable
Object
finalize
method to dispose of
system resources or to perform other cleanup.
The general contract of finalize
is that it is invoked
if and when the JavaTM virtual
machine has determined that there is no longer any
means by which this object can be accessed by any thread that has
not yet died, except as a result of an action taken by the
finalization of some other object or class which is ready to be
finalized. The finalize
method may take any action, including
making this object available again to other threads; the usual purpose
of finalize
, however, is to perform cleanup actions before
the object is irrevocably discarded. For example, the finalize method
for an object that represents an input/output connection might perform
explicit I/O transactions to break the connection before the object is
permanently discarded.
The finalize
method of class Object
performs no
special action; it simply returns normally. Subclasses of
Object
may override this definition.
The Java programming language does not guarantee which thread will
invoke the finalize
method for any given object. It is
guaranteed, however, that the thread that invokes finalize will not
be holding any user-visible synchronization locks when finalize is
invoked. If an uncaught exception is thrown by the finalize method,
the exception is ignored and finalization of that object terminates.
After the finalize
method has been invoked for an object, no
further action is taken until the Java virtual machine has again
determined that there is no longer any means by which this object can
be accessed by any thread that has not yet died, including possible
actions by other objects or classes which are ready to be finalized,
at which point the object may be discarded.
The finalize
method is never invoked more than once by a Java
virtual machine for any given object.
Any exception thrown by the finalize
method causes
the finalization of this object to be halted, but is otherwise
ignored.