SpringBoot中关于Fegin调用报错：failed and no fallback available

        首先不能随意导入依赖，因为在openapi-gateway部分里面导入了openapi-cache的依赖以致于我在openapi-gateway里面使用CacheService被认为需要再次使用openapi-cache模块里通过gitee才能连接redis。

        其次，在CacheService添加下面的注释之后要编写相应的Fallback文件

@FeignClient(value ="OPENAPI-CACHE" ,fallback = CacheServiceFallback.class)

         CacheServiceFallback代码如下：

package com.zgz.openplatform.gateway.feign;

import com.netflix.hystrix.contrib.javanica.annotation.HystrixCommand;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Component;
import org.springframework.web.bind.annotation.*;

import java.util.Map;
import java.util.Set;
import java.util.concurrent.TimeUnit;



@Component
public class CacheServiceFallback   implements CacheService{

    //日志在logback-spring.xml里面写好了，这里调用一下
    private static Logger logger = LoggerFactory.getLogger(CacheServiceFallback.class);

    
    public boolean save2Redis( String key, String value, long expireTime) throws Exception {
        logger.error("save2Redis出现异常进行降级,{},{}",key,value);         //打印出日志里面记录的异常
        return false;
    }


    public String getFromRedis( String key) throws Exception {
        logger.error("getFromRedis出现异常进行降级,{}",key);
        return null;
    }


    public boolean deleteKey( String key) throws Exception {
        logger.error("save2Redis出现异常进行降级,{}",key);         //打印出日志里面记录的异常
        return false;
    }


    public boolean expire( String key,  long expireTime) throws Exception {
        logger.error("save2Redis出现异常进行降级,{}",key);         //打印出日志里面记录的异常
        return false;
    }

    public Long getAutoIncrementId( String key) throws Exception {
        logger.error("getautoincrementidFallBack出现异常进行降级,{}",key);         //打印出日志里面记录的异常
        return null;
    }

    public Set