From 46f56338de571f2d2e3d5752eafd0b38dc698da5 Mon Sep 17 00:00:00 2001 From: erik Date: Thu, 8 Feb 2007 12:48:51 +0000 Subject: [PATCH 1/1] --- .../java/org/wamblee/io/DirectoryMonitor.java | 80 +++++++++++++++++++ 1 file changed, 80 insertions(+) create mode 100644 support/src/main/java/org/wamblee/io/DirectoryMonitor.java diff --git a/support/src/main/java/org/wamblee/io/DirectoryMonitor.java b/support/src/main/java/org/wamblee/io/DirectoryMonitor.java new file mode 100644 index 00000000..5fe2e573 --- /dev/null +++ b/support/src/main/java/org/wamblee/io/DirectoryMonitor.java @@ -0,0 +1,80 @@ +/* + * Copyright 2006 the original author or authors. + * + * 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 org.wamblee.io; + +import java.io.File; +import java.io.FileFilter; +import java.util.ArrayList; +import java.util.Date; +import java.util.HashMap; +import java.util.List; +import java.util.Map; + +import org.apache.commons.logging.Log; +import org.apache.commons.logging.LogFactory; + +/** + * Monitors a directory for changes. + */ +public class DirectoryMonitor { + + private static final Log LOG = LogFactory.getLog(DirectoryMonitor.class); + + public static interface Listener { + void fileChanged(File aFile); + void fileCreated(File aFile); + void fileDeleted(File aFile); + }; + + private File _directory; + private FileFilter _filter; + private Listener _listener; + private Map _contents; + + public DirectoryMonitor(File aDirectory, FileFilter aFilefilter, Listener aListener) { + _directory = aDirectory; + _filter = aFilefilter; + _listener = aListener; + _contents = new HashMap(); + } + + public void poll() { + LOG.info("Polling " + _directory); + Map newContents = new HashMap(); + File[] files = _directory.listFiles(_filter); + for (File file: files) { + if ( _contents.containsKey(file)) { + Date oldDate = _contents.get(file); + if (file.lastModified() != oldDate.getTime()) { + _listener.fileChanged(file); + } else { + // No change. + } + _contents.remove(file); + newContents.put(file, new Date(file.lastModified())); + } else { + _listener.fileCreated(file); + newContents.put(file, new Date(file.lastModified())); + } + } + for (File file: _contents.keySet()) { + _listener.fileDeleted(file); + } + _contents = newContents; + } + +} -- 2.31.1