springboot 基于google 缓存，实现防重复提交

在Spring Boot应用中，可以使用Google Guava缓存来实现防重复提交功能。Guava提供了强大的缓存机制，可以方便地实现对请求的去重处理。。

1. 添加依赖

首先，在你的pom.xml文件中添加Guava的依赖：

<dependency><groupId>com.google.guava</groupId><artifactId>guava</artifactId><version>31.0.1-jre</version>
</dependency>

2. 创建缓存配置类

创建一个配置类来初始化Guava缓存：

import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;import java.util.concurrent.TimeUnit;@Configuration
public class CacheConfig {@Beanpublic Cache<String, String> requestCache() {return CacheBuilder.newBuilder().expireAfterWrite(5, TimeUnit.MINUTES) // 设置缓存过期时间.build();}
}

3. 创建防重复提交拦截器

接下来，创建一个拦截器来检查请求是否重复：

import com.google.common.cache.Cache;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.servlet.HandlerInterceptor;import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;@Component
public class DuplicateSubmissionInterceptor implements HandlerInterceptor {@Autowiredprivate Cache<String, String> requestCache;@Overridepublic boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {String key = generateKey(request);if (key != null && requestCache.getIfPresent(key) != null) {response.setStatus(HttpServletResponse.SC_CONFLICT); // 409 Conflictreturn false;} else {requestCache.put(key, "");return true;}}private String generateKey(HttpServletRequest request) {// 根据请求生成唯一键，例如可以根据URL和参数生成MD5值String url = request.getRequestURI();String queryString = request.getQueryString();return url + (queryString != null ? "?" + queryString : "");}
}

4. 注册拦截器

最后，将拦截器注册到Spring MVC中：

mport org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.InterceptorRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;@Configuration
public class WebConfig implements WebMvcConfigurer {@Autowiredprivate DuplicateSubmissionInterceptor duplicateSubmissionInterceptor;@Overridepublic void addInterceptors(InterceptorRegistry registry) {registry.addInterceptor(duplicateSubmissionInterceptor).addPathPatterns("/**"); // 对所有请求进行拦截}
}