com.electronwill.nightconfig.core.file

Class FileWatcher

java.lang.Object

com.electronwill.nightconfig.core.file.FileWatcher

public final class FileWatcher
extends java.lang.Object

A FileWatcher can watch several files asynchronously.

New watches are added with the addWatch(Path, Runnable) method, which specifies the task to execute when the file is modified.

This class is thread-safe.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FileWatcher.WatchingException

Constructor Summary

Constructors

Constructor and Description
FileWatcher() Creates a new FileWatcher with a default exception handler and a default debounce time.
FileWatcher(java.util.function.Consumer<java.lang.Exception> exceptionHandler) Creates a new FileWatcher with the default debounce time and the given exception handler.
FileWatcher(java.time.Duration debounceTime) Creates a new FileWatcher with a default exception handler.
FileWatcher(java.time.Duration debounceTime, java.util.function.Consumer<java.lang.Throwable> exceptionHandler) Creates a new FileWatcher with the given exception handler.

Method Summary

Modifier and Type	Method and Description
void	addWatch(java.io.File file, java.lang.Runnable changeHandler) Watches a file, if not already watched by this FileWatcher.
void	addWatch(java.nio.file.Path file, java.lang.Runnable changeHandler) Watches a file, if not already watched by this FileWatcher.
static FileWatcher	defaultInstance() Gets the default, global instance of FileWatcher.
void	removeWatch(java.io.File file) Stops watching a file.
void	removeWatch(java.nio.file.Path file) Stops watching a file.
void	setWatch(java.io.File file, java.lang.Runnable changeHandler) Watches a file.
void	setWatch(java.nio.file.Path file, java.lang.Runnable changeHandler) Watches a file.
void	stop() Stops this FileWatcher.

Methods inherited from class java.lang.Object

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

Constructor Detail

FileWatcher

public FileWatcher()

Creates a new FileWatcher with a default exception handler and a default debounce time. The default exception handler is simply: (e) -> e.printStackTrace(); The default debounce time is unspecified and may change in the future, but is typically around 1 second or less.

FileWatcher

public FileWatcher(java.util.function.Consumer<java.lang.Exception> exceptionHandler)

Creates a new FileWatcher with the default debounce time and the given exception handler.

The default debounce time is unspecified and may change in the future, but is typically around 1 second or less.

FileWatcher

public FileWatcher(java.time.Duration debounceTime)

Creates a new FileWatcher with a default exception handler. The default exception handler is simply: (e) -> e.printStackTrace();

Parameters:

debounceTime - hwo much time to wait after each modification of a file before triggering the change handler

FileWatcher

public FileWatcher(java.time.Duration debounceTime,
                   java.util.function.Consumer<java.lang.Throwable> exceptionHandler)

Creates a new FileWatcher with the given exception handler.

Parameters:

debounceTime - delay between each call of the file's changeHandler.

exceptionHandler - called when an exception occurs during the handling of file events

Method Detail

defaultInstance

public static FileWatcher defaultInstance()

Gets the default, global instance of FileWatcher. If the previous global instance has been stopped, create and start a new instance.

Returns:

the default FileWatcher

addWatch

public void addWatch(java.io.File file,
                     java.lang.Runnable changeHandler)

Watches a file, if not already watched by this FileWatcher. The file's parent directory must exist.

Parameters:

file - the file to watch

changeHandler - the handler to call when the file is modified

addWatch

public void addWatch(java.nio.file.Path file,
                     java.lang.Runnable changeHandler)

Watches a file, if not already watched by this FileWatcher. The file's parent directory must exist.

Parameters:

file - the file to watch

changeHandler - the handler to call when the file is modified

setWatch

public void setWatch(java.io.File file,
                     java.lang.Runnable changeHandler)

Watches a file. If the file is already watched by this FileWatcher, its changeHandler is replaced. The file's parent directory must exist.

Parameters:

file - the file to watch

changeHandler - the handler to call when the file is modified

setWatch

public void setWatch(java.nio.file.Path file,
                     java.lang.Runnable changeHandler)

Watches a file. If the file is already watched by this FileWatcher, its changeHandler is replaced. The file's parent directory must exist.

Parameters:

file - the file to watch

changeHandler - the handler to call when the file is modified

removeWatch

public void removeWatch(java.io.File file)

Stops watching a file.

Parameters:

file - the file to stop watching

removeWatch

public void removeWatch(java.nio.file.Path file)

Stops watching a file.

Parameters:

file - the file to stop watching

stop

public void stop()

Stops this FileWatcher. The underlying ressources (ie the WatchServices) are closed, and the file modification handlers won't be called anymore.