Guava之controller中使用缓存cache

之前介绍过的Guava这个工具包中有很多方便的用法，下面要使用它封装的Cache来实现功能.

示例：

[code=java;toolbar:true">[code]import com.google.common.cache.CacheBuilder;
import com.google.common.cache.CacheLoader;
import com.google.common.cache.LoadingCache;
import org.joda.time.DateTime;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;

import java.util.List;
import java.util.concurrent.TimeUnit;

@RestController
@RequestMapping("/hello")
public class HelloController {

private static Logger logger = LoggerFactory.getLogger(HelloController .class);

public static LoadingCache<String,Object> cacheBuilder;

@Autowired
private OverviewService overviewService;

static OverviewParameter op ;

@RequestMapping(value="/hh",method=RequestMethod.GET)
public Result<?> sayHello(OverviewParameter overviewParameter){
Result<?> result = null;
setOviewParameter(overviewParameter);
ObjectResultEx<SummaryVo> resObj = (ObjectResultEx<SummaryVo>) getDataInCache("summary", overviewParameter);
...
return result;
}

/**
* 根据键值获取缓存中的数据
*/
private Object getDataInCache(final String key, OverviewParameter overviewParameter){
logger.info("before refresh cache, key:{}, param:{}",key, JSONObject.toJSONString(overviewParameter));
op = overviewParameter;
try {
if ((cacheBuilder != null) && ((ObjectResultEx) cacheBuilder.get(key)).isSuccess()){
return cacheBuilder.get(key);
}else {
return commonCache(new CacheLoader<String, Object>() {
@Override
public Object load(String key) throws Exception {
logger.info("refresh cache, key:{}, param:{}",key, JSONObject.toJSONString(op));
switch (key){
case "summary":
return overviewService.overviewSummary(op);
case "grantNums":
return overviewService.overviewGrantNums(op);
case "creditNums":
return overviewService.overviewCreditNums(op);
case "riskNums":
return overviewService.overviewRiskNums(op);
default:
return new ObjectResultEx<>().makeFailedResult();
}
}
}).get(key);
}
} catch (Exception e) {
logger.error("获取缓存中的数据出错", e);
}
return new ObjectResultEx<>().makeFailedResult();
}

/**
* 为缓存设置loader
*/
private LoadingCache<String, Object> commonCache(CacheLoader<String, Object> loader) {
synchronized (logger){
cacheBuilder = CacheBuilder
.newBuilder()
.refreshAfterWrite(1, TimeUnit.MINUTES)
.build(