FileObserver

ACCESS

static val ACCESS: Int

Event type: Data was read from a file

Value: 1

ALL_EVENTS

static val ALL_EVENTS: Int

Event mask: All valid event types, combined.
Value is either 0 or a combination of the following:

• ACCESS
• MODIFY
• ATTRIB
• CLOSE_WRITE
• CLOSE_NOWRITE
• OPEN
• MOVED_FROM
• MOVED_TO
• CREATE
• DELETE
• DELETE_SELF
• MOVE_SELF

Value: 4095

ATTRIB

static val ATTRIB: Int

Event type: Metadata (permissions, owner, timestamp) was changed explicitly

Value: 4

CLOSE_NOWRITE

static val CLOSE_NOWRITE: Int

Event type: Someone had a file or directory open read-only, and closed it

Value: 16

CLOSE_WRITE

static val CLOSE_WRITE: Int

Event type: Someone had a file or directory open for writing, and closed it

Value: 8

CREATE

static val CREATE: Int

Event type: A new file or subdirectory was created under the monitored directory

Value: 256

DELETE

static val DELETE: Int

Event type: A file was deleted from the monitored directory

Value: 512

DELETE_SELF

static val DELETE_SELF: Int

Event type: The monitored file or directory was deleted; monitoring effectively stops

Value: 1024

MODIFY

static val MODIFY: Int

Event type: Data was written to a file

Value: 2

MOVED_FROM

static val MOVED_FROM: Int

Event type: A file or subdirectory was moved from the monitored directory

Value: 64

MOVED_TO

static val MOVED_TO: Int

Event type: A file or subdirectory was moved to the monitored directory

Value: 128

MOVE_SELF

static val MOVE_SELF: Int

Event type: The monitored file or directory was moved; monitoring continues

Value: 2048

OPEN

static val OPEN: Int

Event type: A file or directory was opened

Value: 32

FileObserver

FileObserver(file: File)

Equivalent to FileObserver(file, FileObserver.ALL_EVENTS).

FileObserver

FileObserver(
    file: File, 
    mask: Int)

Create a new file observer for a certain file or directory. Monitoring does not start on creation! You must call startWatching() before you will receive events.

FileObserver

FileObserver(path: String!)

Deprecated: use FileObserver(java.io.File) instead.

Equivalent to FileObserver(path, FileObserver.ALL_EVENTS).

FileObserver

FileObserver(
    path: String!, 
    mask: Int)

Deprecated: use FileObserver(java.io.File,int) instead.

Create a new file observer for a certain file or directory. Monitoring does not start on creation! You must call startWatching() before you will receive events.

FileObserver

FileObserver(files: MutableList<File!>)

Equivalent to FileObserver(paths, FileObserver.ALL_EVENTS).

FileObserver

FileObserver(
    files: MutableList<File!>, 
    mask: Int)

Version of FileObserver(java.io.File,int) that allows callers to monitor multiple files or directories.

onEvent

abstract fun onEvent(
    event: Int, 
    path: String?
): Unit

The event handler, which must be implemented by subclasses.

This method is invoked on a special FileObserver thread. It runs independently of any threads, so take care to use appropriate synchronization! Consider using Handler.post(Runnable) to shift event handling work to the main thread to avoid concurrency problems.

Event handlers must not throw exceptions.

startWatching

open fun startWatching(): Unit

Start watching for events. The monitored file or directory must exist at this time, or else no events will be reported (even if it appears later). If monitoring is already started, this call has no effect.

stopWatching

open fun stopWatching(): Unit

Stop watching for events. Some events may be in process, so events may continue to be reported even after this method completes. If monitoring is already stopped, this call has no effect.

finalize

protected open fun finalize(): Unit

Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. A subclass overrides the 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 Java 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.