SpringMVC 限流的範例程式碼，springmvc範例程式碼

SpringMVC 限流的範例程式碼，springmvc範例程式碼

在使用SpringBoot做介面訪問如何做介面的限流，這裡我們可以使用google的Guava包來實現，當然我們也可以自己實現限流，Guava中的限流是久經考驗的我們沒必需重新再去寫一個，如果想瞭解限流原理的同學可以自己查閱一下相關的資料，本文不作過來說明噢。

使用說明

在項目中引入Guava相關包

http://mvnrepository.com/artifact/com.google.guava/guava/21.0

maven項目

<!-- https://mvnrepository.com/artifact/com.google.guava/guava --><dependency>  <groupId>com.google.guava</groupId>  <artifactId>guava</artifactId>  <version>21.0</version></dependency>

gradle項目

// https://mvnrepository.com/artifact/com.google.guava/guavacompile group: 'com.google.guava', name: 'guava', version: '21.0'

寫一個SpringMVC的攔截器

SmoothBurstyInterceptor.java

import com.google.common.util.concurrent.RateLimiter;import org.springframework.web.servlet.ModelAndView;import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.util.concurrent.TimeUnit;public class SmoothBurstyInterceptor extends HandlerInterceptorAdapter {  public enum LimitType {    DROP,//丟棄    WAIT //等待  }  /**   * 限流器   */  private RateLimiter limiter;  /**   * 限流方式   */  private LimitType limitType = LimitType.DROP;  public SmoothBurstyInterceptor() {    this.limiter = RateLimiter.create(10);  }  /**   * @param tps    限流量 (每秒處理量)   * @param limitType 限流類型:等待/丟棄(達到限流量)   */  public SmoothBurstyInterceptor(int tps, SmoothBurstyInterceptor.LimitType limitType) {    this.limiter = RateLimiter.create(tps);    this.limitType = limitType;  }  /**   * @param permitsPerSecond 每秒新增的令牌數   * @param limitType 限流類型:等待/丟棄(達到限流量)   */  public SmoothBurstyInterceptor(double permitsPerSecond, SmoothBurstyInterceptor.LimitType limitType) {    this.limiter = RateLimiter.create(permitsPerSecond, 1000, TimeUnit.MILLISECONDS);    this.limitType = limitType;  }  @Override  public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {    if (limitType.equals(LimitType.DROP)) {      if (limiter.tryAcquire()) {        return super.preHandle(request, response, handler);      }    } else {      limiter.acquire();      return super.preHandle(request, response, handler);    }    throw new Exception("網路異常!");//達到限流後，往頁面提示的錯誤資訊。  }  @Override  public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {    super.postHandle(request, response, handler, modelAndView);  }  @Override  public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {    super.afterCompletion(request, response, handler, ex);  }  public RateLimiter getLimiter() {    return limiter;  }  public void setLimiter(RateLimiter limiter) {    this.limiter = limiter;  }}

SpringMVC攔截配置

WebConfig.java

@Componentpublic class WebConfig extends WebMvcConfigurerAdapter {  @Override  public void addInterceptors(InterceptorRegistry registry) {    // 多個攔截器組成一個攔截器鏈    registry.addInterceptor(new SmoothBurstyInterceptor(100, SmoothBurstyInterceptor.LimitType.DROP)).addPathPatterns("/**");    //限流可配置為SmoothBurstyInterceptor.LimitType.DROP丟棄請求或者SmoothBurstyInterceptor.LimitType.WAIT等待，100為每秒的速率    super.addInterceptors(registry);  }}

以上就是本文的全部內容，希望對大家的學習有所協助，也希望大家多多支援幫客之家。