一、異步執(zhí)行

實(shí)現(xiàn)方式二種：

1.使用異步注解@aysnc、啟動(dòng)類：添加@EnableAsync注解

2.JDK 8本身有一個(gè)非常好用的Future類——CompletableFuture

@AllArgsConstructorpublic class AskThread implements Runnable{ private CompletableFuture<Integer> re = null; public void run() { int myRe = 0; try { myRe = re.get() * re.get(); } catch (Exception e) { e.printStackTrace(); } System.out.println(myRe); } public static void main(String[] args) throws InterruptedException { final CompletableFuture<Integer> future = new CompletableFuture<>(); new Thread(new AskThread(future)).start(); //模擬長(zhǎng)時(shí)間的計(jì)算過(guò)程 Thread.sleep(1000); //告知完成結(jié)果 future.complete(60); }}

在該示例中，啟動(dòng)一個(gè)線程，此時(shí)AskThread對(duì)象還沒(méi)有拿到它需要的數(shù)據(jù)，執(zhí)行到 myRe = re.get() * re.get()會(huì)阻塞。我們用休眠1秒來(lái)模擬一個(gè)長(zhǎng)時(shí)間的計(jì)算過(guò)程，并將計(jì)算結(jié)果告訴future執(zhí)行結(jié)果，AskThread線程將會(huì)繼續(xù)執(zhí)行。

public class Calc { public static Integer calc(Integer para) { try { //模擬一個(gè)長(zhǎng)時(shí)間的執(zhí)行 Thread.sleep(1000); } catch (InterruptedException e) { e.printStackTrace(); } return para * para; } public static void main(String[] args) throws ExecutionException, InterruptedException { final CompletableFuture<Void> future = CompletableFuture.supplyAsync(() -> calc(50)) .thenApply((i) -> Integer.toString(i)) .thenApply((str) -> ''' + str + ''') .thenAccept(System.out::println); future.get(); }}

CompletableFuture.supplyAsync方法構(gòu)造一個(gè)CompletableFuture實(shí)例，在supplyAsync()方法中，它會(huì)在一個(gè)新線程中，執(zhí)行傳入的參數(shù)。在這里它會(huì)執(zhí)行calc()方法，這個(gè)方法可能是比較慢的，但這并不影響CompletableFuture實(shí)例的構(gòu)造速度，supplyAsync()會(huì)立即返回。

而返回的CompletableFuture實(shí)例就可以作為這次調(diào)用的契約，在將來(lái)任何場(chǎng)合，用于獲得最終的計(jì)算結(jié)果。supplyAsync用于提供返回值的情況，CompletableFuture還有一個(gè)不需要返回值的異步調(diào)用方法runAsync(Runnable runnable),一般我們?cè)趦?yōu)化Controller時(shí)，使用這個(gè)方法比較多。

這兩個(gè)方法如果在不指定線程池的情況下，都是在ForkJoinPool.common線程池中執(zhí)行，而這個(gè)線程池中的所有線程都是Daemon（守護(hù)）線程，所以，當(dāng)主線程結(jié)束時(shí)，這些線程無(wú)論執(zhí)行完畢都會(huì)退出系統(tǒng)。

核心代碼：

CompletableFuture.runAsync(() -> this.afterBetProcessor(betRequest,betDetailResult,appUser,id));

異步調(diào)用使用Callable來(lái)實(shí)現(xiàn)

@RestController public class HelloController { private static final Logger logger = LoggerFactory.getLogger(HelloController.class); @Autowired private HelloService hello; @GetMapping('/helloworld') public String helloWorldController() { return hello.sayHello(); } /** * 異步調(diào)用restful * 當(dāng)controller返回值是Callable的時(shí)候，springmvc就會(huì)啟動(dòng)一個(gè)線程將Callable交給TaskExecutor去處理 * 然后DispatcherServlet還有所有的spring攔截器都退出主線程，然后把response保持打開(kāi)的狀態(tài) * 當(dāng)Callable執(zhí)行結(jié)束之后，springmvc就會(huì)重新啟動(dòng)分配一個(gè)request請(qǐng)求，然后DispatcherServlet就重新 * 調(diào)用和處理Callable異步執(zhí)行的返回結(jié)果， 然后返回視圖 * * @return */ @GetMapping('/hello') public Callable<String> helloController() { logger.info(Thread.currentThread().getName() + ' 進(jìn)入helloController方法'); Callable<String> callable = new Callable<String>() { @Override public String call() throws Exception { logger.info(Thread.currentThread().getName() + ' 進(jìn)入call方法'); String say = hello.sayHello(); logger.info(Thread.currentThread().getName() + ' 從helloService方法返回'); return say; } }; logger.info(Thread.currentThread().getName() + ' 從helloController方法返回'); return callable; } }

異步調(diào)用的方式 WebAsyncTask

@RestController public class HelloController { private static final Logger logger = LoggerFactory.getLogger(HelloController.class); @Autowired private HelloService hello; /** * 帶超時(shí)時(shí)間的異步請(qǐng)求 通過(guò)WebAsyncTask自定義客戶端超時(shí)間 * * @return */ @GetMapping('/world') public WebAsyncTask<String> worldController() { logger.info(Thread.currentThread().getName() + ' 進(jìn)入helloController方法'); // 3s鐘沒(méi)返回，則認(rèn)為超時(shí) WebAsyncTask<String> webAsyncTask = new WebAsyncTask<>(3000, new Callable<String>() { @Override public String call() throws Exception { logger.info(Thread.currentThread().getName() + ' 進(jìn)入call方法'); String say = hello.sayHello(); logger.info(Thread.currentThread().getName() + ' 從helloService方法返回'); return say; } }); logger.info(Thread.currentThread().getName() + ' 從helloController方法返回'); webAsyncTask.onCompletion(new Runnable() { @Override public void run() { logger.info(Thread.currentThread().getName() + ' 執(zhí)行完畢'); } }); webAsyncTask.onTimeout(new Callable<String>() { @Override public String call() throws Exception { logger.info(Thread.currentThread().getName() + ' onTimeout'); // 超時(shí)的時(shí)候，直接拋異常，讓外層統(tǒng)一處理超時(shí)異常 throw new TimeoutException('調(diào)用超時(shí)'); } }); return webAsyncTask; } /** * 異步調(diào)用，異常處理，詳細(xì)的處理流程見(jiàn)MyExceptionHandler類 * * @return */ @GetMapping('/exception') public WebAsyncTask<String> exceptionController() { logger.info(Thread.currentThread().getName() + ' 進(jìn)入helloController方法'); Callable<String> callable = new Callable<String>() { @Override public String call() throws Exception { logger.info(Thread.currentThread().getName() + ' 進(jìn)入call方法'); throw new TimeoutException('調(diào)用超時(shí)!'); } }; logger.info(Thread.currentThread().getName() + ' 從helloController方法返回'); return new WebAsyncTask<>(20000, callable); } }

二、增加內(nèi)嵌Tomcat的最大連接數(shù)

@Configurationpublic class TomcatConfig { @Bean public ConfigurableServletWebServerFactory webServerFactory() { TomcatServletWebServerFactory tomcatFactory = new TomcatServletWebServerFactory(); tomcatFactory.addConnectorCustomizers(new MyTomcatConnectorCustomizer()); tomcatFactory.setPort(8005); tomcatFactory.setContextPath('/api-g'); return tomcatFactory; } class MyTomcatConnectorCustomizer implements TomcatConnectorCustomizer { public void customize(Connector connector) { Http11NioProtocol protocol = (Http11NioProtocol) connector.getProtocolHandler(); //設(shè)置最大連接數(shù) protocol.setMaxConnections(20000); //設(shè)置最大線程數(shù) protocol.setMaxThreads(2000); protocol.setConnectionTimeout(30000); } }}

三、使用@ComponentScan()定位掃包比@SpringBootApplication掃包更快

四、默認(rèn)tomcat容器改為Undertow（Jboss下的服務(wù)器，Tomcat吞吐量5000，Undertow吞吐量8000）

<exclusions> <exclusion> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </exclusion></exclusions>

改為:

<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-undertow</artifactId></dependency>

五、使用 BufferedWriter 進(jìn)行緩沖

六、Deferred方式實(shí)現(xiàn)異步調(diào)用

@RestControllerpublic class AsyncDeferredController { private final Logger logger = LoggerFactory.getLogger(this.getClass()); private final LongTimeTask taskService; @Autowired public AsyncDeferredController(LongTimeTask taskService) { this.taskService = taskService; } @GetMapping('/deferred') public DeferredResult<String> executeSlowTask() { logger.info(Thread.currentThread().getName() + '進(jìn)入executeSlowTask方法'); DeferredResult<String> deferredResult = new DeferredResult<>(); // 調(diào)用長(zhǎng)時(shí)間執(zhí)行任務(wù) taskService.execute(deferredResult); // 當(dāng)長(zhǎng)時(shí)間任務(wù)中使用deferred.setResult('world');這個(gè)方法時(shí)，會(huì)從長(zhǎng)時(shí)間任務(wù)中返回，繼續(xù)controller里面的流程 logger.info(Thread.currentThread().getName() + '從executeSlowTask方法返回'); // 超時(shí)的回調(diào)方法 deferredResult.onTimeout(new Runnable(){ @Override public void run() { logger.info(Thread.currentThread().getName() + ' onTimeout'); // 返回超時(shí)信息 deferredResult.setErrorResult('time out!'); } }); // 處理完成的回調(diào)方法，無(wú)論是超時(shí)還是處理成功，都會(huì)進(jìn)入這個(gè)回調(diào)方法 deferredResult.onCompletion(new Runnable(){ @Override public void run() { logger.info(Thread.currentThread().getName() + ' onCompletion'); } }); return deferredResult; }}

七、異步調(diào)用可以使用AsyncHandlerInterceptor進(jìn)行攔截

@Componentpublic class MyAsyncHandlerInterceptor implements AsyncHandlerInterceptor { private static final Logger logger = LoggerFactory.getLogger(MyAsyncHandlerInterceptor.class); @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { return true; } @Override public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {// HandlerMethod handlerMethod = (HandlerMethod) handler; logger.info(Thread.currentThread().getName()+ '服務(wù)調(diào)用完成，返回結(jié)果給客戶端'); } @Override public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception { if(null != ex){ System.out.println('發(fā)生異常:'+ex.getMessage()); } } @Override public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { // 攔截之后，重新寫回?cái)?shù)據(jù)，將原來(lái)的hello world換成如下字符串 String resp = 'my name is chhliu!'; response.setContentLength(resp.length()); response.getOutputStream().write(resp.getBytes()); logger.info(Thread.currentThread().getName() + ' 進(jìn)入afterConcurrentHandlingStarted方法'); } }

以上這篇基于Springboot吞吐量?jī)?yōu)化解決方案就是小編分享給大家的全部?jī)?nèi)容了，希望能給大家一個(gè)參考，也希望大家多多支持好吧啦網(wǎng)。