From 0dcf4f9acad3226bcebe29d9b10623543f5004f6 Mon Sep 17 00:00:00 2001
From: Looly <loolly@gmail.com>
Date: Sun, 2 Aug 2020 20:38:04 +0800
Subject: [PATCH] add WatchAction

---
 CHANGELOG.md                                  |  1 +
 .../cn/hutool/core/io/watch/WatchAction.java  | 24 +++++++++++++++++
 .../cn/hutool/core/io/watch/WatchServer.java  | 27 ++++++++++++++-----
 3 files changed, 45 insertions(+), 7 deletions(-)
 create mode 100644 hutool-core/src/main/java/cn/hutool/core/io/watch/WatchAction.java

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 39ef56c3c..316033d7e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -10,6 +10,7 @@
 * 【core  】     StrUtil增加filter方法（pr#149@Gitee）
 * 【core  】     DateUtil增加beginOfWeek重载
 * 【core  】     将有歧义的BeanUtil.mapToBean方法置为过期（使用toBean方法）
+* 【core  】     添加WatchAction（对Watcher的抽象）
 
 ### Bug修复#
 * 【core  】     修复原始类型转换时，转换失败没有抛出异常的问题
diff --git a/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchAction.java b/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchAction.java
new file mode 100644
index 000000000..34f4e45ea
--- /dev/null
+++ b/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchAction.java
@@ -0,0 +1,24 @@
+package cn.hutool.core.io.watch;
+
+import java.nio.file.Path;
+import java.nio.file.WatchEvent;
+
+/**
+ * 监听事件处理函数接口
+ *
+ * @author looly
+ * @since 5.4.0
+ */
+@FunctionalInterface
+public interface WatchAction {
+
+	/**
+	 * 事件处理，通过实现此方法处理各种事件。
+	 *
+	 * 事件可以调用 {@link WatchEvent#kind()}获取，对应事件见{@link WatchKind}
+	 *
+	 * @param event       事件
+	 * @param currentPath 事件发生的当前Path路径
+	 */
+	void doAction(WatchEvent<?> event, Path currentPath);
+}
diff --git a/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchServer.java b/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchServer.java
index 342ca0cb8..5d26441b5 100644
--- a/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchServer.java
+++ b/hutool-core/src/main/java/cn/hutool/core/io/watch/WatchServer.java
@@ -129,10 +129,11 @@ public class WatchServer extends Thread implements Closeable, Serializable {
 	/**
 	 * 执行事件获取并处理
 	 *
-	 * @param watcher     {@link Watcher}
+	 * @param action     监听回调函数，实现此函数接口用于处理WatchEvent事件
 	 * @param watchFilter 监听过滤接口，通过实现此接口过滤掉不需要监听的情况，null表示不过滤
+	 * @since 5.4.0
 	 */
-	public void watch(Watcher watcher, Filter<WatchEvent<?>> watchFilter) {
+	public void watch(WatchAction action, Filter<WatchEvent<?>> watchFilter) {
 		WatchKey wk;
 		try {
 			wk = watchService.take();
@@ -142,15 +143,28 @@ public class WatchServer extends Thread implements Closeable, Serializable {
 		}
 
 		final Path currentPath = watchKeyPathMap.get(wk);
-		WatchEvent.Kind<?> kind;
-		for (WatchEvent<?> event : wk.pollEvents()) {
-			kind = event.kind();
 
+		for (WatchEvent<?> event : wk.pollEvents()) {
 			// 如果监听文件，检查当前事件是否与所监听文件关联
 			if (null != watchFilter && false == watchFilter.accept(event)) {
 				continue;
 			}
 
+			action.doAction(event, currentPath);
+		}
+		wk.reset();
+	}
+
+	/**
+	 * 执行事件获取并处理
+	 *
+	 * @param watcher     {@link Watcher}
+	 * @param watchFilter 监听过滤接口，通过实现此接口过滤掉不需要监听的情况，null表示不过滤
+	 */
+	public void watch(Watcher watcher, Filter<WatchEvent<?>> watchFilter) {
+		watch((event, currentPath)->{
+			WatchEvent.Kind<?> kind = event.kind();
+
 			if (kind == StandardWatchEventKinds.ENTRY_CREATE) {
 				watcher.onCreate(event, currentPath);
 			} else if (kind == StandardWatchEventKinds.ENTRY_MODIFY) {
@@ -160,8 +174,7 @@ public class WatchServer extends Thread implements Closeable, Serializable {
 			} else if (kind == StandardWatchEventKinds.OVERFLOW) {
 				watcher.onOverflow(event, currentPath);
 			}
-		}
-		wk.reset();
+		}, watchFilter);
 	}
 
 	/**