<!--Java项目广泛依赖 的核心库-->
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>23.0</version>
</dependency>
package com.citydo.dialogue.controller;
import com.google.common.util.concurrent.RateLimiter;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RestController;
import java.util.Collections;
@RestController
public class HomeController {
// 这里的1表示每秒允许处理的量为10个
private RateLimiter limiter = RateLimiter.create(10.0);
//RateLimiter.create(doublepermitsPerSecond, long warmupPeriod, TimeUnit unit);
//RateLimiter limiter = RateLimiter.create(5, 1000, TimeUnit.MILLISECONDS);
//permitsPerSecond: 表示 每秒新增 的令牌数
// warmupPeriod: 表示在从 冷启动速率 过渡到 平均速率 的时间间隔
@GetMapping("/test/{name}")
public String Test(@PathVariable("name") String name){
// 请求RateLimiter, 超过permits会被阻塞
final double acquire = limiter.acquire();
System.out.println("--------" acquire);
//判断double是否为空或者为0
if(acquire>=(-1e-6)&&acquire<=(1e-6)){
return name;
}else{
return "操作太频繁";
}
}
}
package com.citydo.dialogue.config;
import com.citydo.dialogue.service.AccessLimitInterceptor;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport;
/**
* 拦截器配置
* @author nick
*/
@Configuration
public class InterceptorConfig extends WebMvcConfigurationSupport {
@Override
public void addInterceptors(InterceptorRegistry registry) {
//addPathPatterns 添加拦截规则
registry.addInterceptor(new AccessLimitInterceptor())
//添加需要拦截请求的路径
.addPathPatterns("/**");
//swagger2 放行 .excludePathPatterns("/swagger-resources/**", "/webjars/**", "/v2/**", "/swagger-ui.html/**");
//.excludePathPatterns("/*")
//去除拦截请求的路径
}
@Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/");
}
}
package com.citydo.dialogue.service;
import com.citydo.dialogue.entity.AccessLimit;
import com.citydo.dialogue.utils.IpUtil;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.concurrent.TimeUnit;
public class AccessLimitInterceptor implements HandlerInterceptor {
//使用RedisTemplate操作redis
@Autowired
private RedisTemplate<String, Integer> redisTemplate;
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
if (handler instanceof HandlerMethod) {
HandlerMethod handlerMethod = (HandlerMethod) handler;
Method method = handlerMethod.getMethod();
if (!method.isAnnotationPresent(AccessLimit.class)) {
return true;
}
AccessLimit accessLimit = method.getAnnotation(AccessLimit.class);
if (accessLimit == null) {
return true;
}
int limit = accessLimit.limit();
int sec = accessLimit.sec();
String key = IpUtil.getIpAddr(request) request.getRequestURI();
//资源唯一标识
String formatDate=new SimpleDateFormat("yyyyMMddHHmm").format(new Date());
//String key="request_" formatDate;
Integer maxLimit = redisTemplate.opsForValue().get(key);
if (maxLimit == null) {
//set时一定要加过期时间
redisTemplate.opsForValue().set(key, 1, sec, TimeUnit.SECONDS);
} else if (maxLimit < limit) {
redisTemplate.opsForValue().set(key, maxLimit 1, sec, TimeUnit.SECONDS);
} else {
output(response, "请求太频繁!");
return false;
}
}
return true;
}
public void output(HttpServletResponse response, String msg) throws IOException {
response.setContentType("application/json;charset=UTF-8");
ServletOutputStream outputStream = null;
try {
outputStream = response.getOutputStream();
outputStream.write(msg.getBytes("UTF-8"));
} catch (IOException e) {
e.printStackTrace();
} finally {
outputStream.flush();
outputStream.close();
}
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
}
@Override
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
}
}
package com.citydo.dialogue.entity;
import java.lang.annotation.*;
@Inherited
@Documented
@Target({ElementType.FIELD,ElementType.TYPE,ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface AccessLimit {
//标识 指定sec时间段内的访问次数限制
int limit() default 5;
//标识 时间段
int sec() default 5;
}
package com.citydo.dialogue.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
/**
* 解决redis乱码问题
* 解决配置问题
* @author nick
*/
@Configuration
public class RedisConfig {
/**
* 此方法解决存储乱码
*/
@Bean
public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) {
RedisTemplate<Object, Object> template = new RedisTemplate<Object, Object>();
template.setConnectionFactory(redisConnectionFactory);
template.setKeySerializer(new StringRedisSerializer());
template.setValueSerializer(new GenericJackson2JsonRedisSerializer());
template.setHashKeySerializer(new GenericJackson2JsonRedisSerializer());
template.setHashValueSerializer(new GenericJackson2JsonRedisSerializer());
template.afterPropertiesSet();
return template;
}
}
try{
if(atomic.incrementAndGet() > 限流数) {
//拒绝请求
} else {
//处理请求
}
} finally {
atomic.decrementAndGet();
}
LoadingCache counter = CacheBuilder.newBuilder()
.expireAfterWrite(2, TimeUnit.SECONDS)
.build(newCacheLoader() {
@Override
public AtomicLong load(Long seconds) throws Exception {
return newAtomicLong(0);
}
});
longlimit =1000;
while(true) {
// 得到当前秒
long currentSeconds = System.currentTimeMillis() /1000;
if(counter.get(currentSeconds).incrementAndGet() > limit) {
System.out.println("限流了: " currentSeconds);
continue;
}
// 业务处理
}