# Reactor Learning

**Repository Path**: tzj2015/reactor-learning

## Basic Information

- **Project Name**: Reactor Learning
- **Description**: No description available
- **Primary Language**: Java
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-04-11
- **Last Updated**: 2021-06-04

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

## JDK 9 Reactive Stream
### 背压

### Flow.class
- Flow
    - Publisher 发布者
    - Subscription 处理器
    - Subscriber 订阅者

## Servlet 3.0
### 异步 Servlet

#### 为什么使用异步Servlet，同步Servlet阻塞了什么?
1. 同步、异步是后台服务器概念，对客户端来讲是同步
2. 异步Servlet不会阻塞Tomcat的Servlet线程,Servlet线程可以同时处理多个请求
3. 同步Servlet阻塞了Servlet线程，多个请求需要排队处理

#### Code
```java
// 开启异步支持
@WebServlet(name = "AsyncServlet", value = "/async", asyncSupported = true)
public class AsyncServlet extends HttpServlet {
    private static final long serialVersionUID = -5652269288262248102L;

    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // 开启异步
        AsyncContext asyncContext = request.startAsync();

        // 执行异步方法
        CompletableFuture.runAsync(() -> doAsyncSomething(asyncContext, asyncContext.getRequest(), asyncContext.getResponse()));
    }

    private void doAsyncSomething(AsyncContext asyncContext, ServletRequest request, ServletResponse response) {
        response.setContentType("text/html");
        try {
            TimeUnit.SECONDS.sleep(4);
            PrintWriter out = response.getWriter();
            out.println("Async Done");
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            asyncContext.complete();
        }
    }
}
```

## Reactor
> reactor = jdk8 stream + jdk9 reactive stream

- **Mono** return 0 - 1
- **Flux** return 1 - N