From 95793600ba2a9e94ce11863ed320463131b165ca Mon Sep 17 00:00:00 2001
From: asahi <mikiyashiki@outlook.com>
Date: Mon, 31 Mar 2025 12:54:04 +0800
Subject: [PATCH] =?UTF-8?q?doc:=20=E9=98=85=E8=AF=BBspring=20reactor?=
 =?UTF-8?q?=E6=96=87=E6=A1=A3?=
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---
 spring/webflux/Reactor.md | 44 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 44 insertions(+)

diff --git a/spring/webflux/Reactor.md b/spring/webflux/Reactor.md
index edf4e6e..e247943 100644
--- a/spring/webflux/Reactor.md
+++ b/spring/webflux/Reactor.md
@@ -37,6 +37,8 @@
       - [异步单线程生成`push`](#异步单线程生成push)
         - [hybird push-pull model](#hybird-push-pull-model)
         - [`sink.onRequest`](#sinkonrequest)
+      - [`onCancel` \& `onDispose`](#oncancel--ondispose)
+      - [Handle](#handle)
 
 
 # Reactor 
@@ -523,5 +525,47 @@ Flux<String> bridge = Flux.create(sink -> {
 });
 ```
 
+#### `onCancel` & `onDispose`
+`sink`支持`onCancel`和`onDispose`回调，其区别如下：
+- `onDispose`回调用于执行cleanup操作，其在`complete`, `error`, `cancel`之后都会被调用。
+- `onCancel`回调用于执行取消操作，其只针对`cancel`执行，并且执行顺序位于cleanup之前
 
+其使用示例如下所示：
+```java
+Flux<String> bridge = Flux.create(sink -> {
+    sink.onRequest(n -> channel.poll(n))
+        .onCancel(() -> channel.cancel())
+        .onDispose(() -> channel.close())
+    });
+```
 
+#### Handle
+`handle`为一个`instance method`（非静态方法），其关联了一个已经存在的source。`Mono`和`Flux`中都存在`handle`方法。
+
+和`generate`类似，`handle`使用`SynchronousSink`，并且只允许逐个发出。`handle`的作用类似`map`和`filter`的组合，可以跳过部分元素，其签名如下
+```java
+Flux<R> handle(BiConsumer<T, SynchronousSink<R>>);
+```
+
+其使用示例如下：
+```java
+public String alphabet(int letterNumber) {
+	if (letterNumber < 1 || letterNumber > 26) {
+		return null;
+	}
+	int letterIndexAscii = 'A' + letterNumber - 1;
+	return "" + (char) letterIndexAscii;
+}
+
+// 由于reactive steam中不允许有null，
+// 故而当通过`alphabet`方法映射可能返回null值时，
+// 可以使用handle对返回值进行过滤，只有不为空时才调用`sink.next`
+Flux<String> alphabet = Flux.just(-1, 30, 13, 9, 20)
+    .handle((i, sink) -> {
+        String letter = alphabet(i); 
+        if (letter != null) 
+            sink.next(letter); 
+    });
+
+alphabet.subscribe(System.out::println);
+```