com.vaadin.base.devserver.FileWatcher Maven / Gradle / Ivy
/*
* Copyright 2000-2024 Vaadin Ltd.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.vaadin.base.devserver;
import java.io.File;
import java.io.IOException;
import java.util.Objects;
import io.methvin.watcher.DirectoryWatcher;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.vaadin.flow.function.SerializableConsumer;
/**
* Watches for the file or sub-directory changes in the given directory.
*/
public class FileWatcher {
private DirectoryWatcher watcher;
/**
* Creates an instance of the file watcher for the given directory.
*
* Reports the changed file or directory as a {@link File} instance to the
* provided consumer.
*
* Watches the files create/delete and directory create/delete events.
*
* @param onChangeConsumer
* to be called when any change detected
* @param watchDirectory
* the directory to watch for changes, cannot be empty
* @throws IOException
*/
public FileWatcher(SerializableConsumer onChangeConsumer,
File watchDirectory) throws IOException {
Objects.requireNonNull(watchDirectory,
"Watch directory cannot be null");
Objects.requireNonNull(onChangeConsumer,
"Change listener cannot be null");
watcher = DirectoryWatcher.builder().path(watchDirectory.toPath())
.listener(e -> {
onChangeConsumer.accept(e.path().toFile());
}).build();
}
/**
* Starts the file watching.
*/
public void start() {
watcher.watchAsync().exceptionally((e) -> {
getLogger().error("Error starting file watcher", e);
return null;
});
}
/**
* Stops the file watching.
*
* @throws IOException
* if an error occurs during stop
*/
public void stop() throws IOException {
watcher.close();
}
private static Logger getLogger() {
return LoggerFactory.getLogger(FileWatcher.class);
}
}