一、限流
public static class RateLimiterChangeHandler {
private static final RateLimiter rateLimiter;
static {
rateLimiter = RateLimiter.create(getQueryLimitSpeed());
}
public static RateLimiter getRateLimiter() {
int queryLimitSpeed = getQueryLimitSpeed();
double curLimitSpeed = rateLimiter.getRate();
if (curLimitSpeed != queryLimitSpeed) {
rateLimiter.setRate(queryLimitSpeed);
}
return rateLimiter;
}
}
//阻塞限流
RateLimiterChangeHandler.getRateLimiter().acquire();
//尝试获取令牌
RateLimiterChangeHandler.getRateLimiter().tryAcquire()
二、线程池
private static ExecutorService executorService = new ThreadPoolExecutor(10, 100, 60L,
TimeUnit.SECONDS, new ArrayBlockingQueue<Runnable>(500), Executors.defaultThreadFactory(), new ThreadPoolExecutor.CallerRunsPolicy());
executorService.submit(new Runnable() {
@Override
public void run() {
try {
} catch (InterruptedException e) {
} finally {
}
}
});
三、重试
for (int retry = 0; retry < 3; retry++) {
try {
……
break;
} catch (Exception e) {
}
}
四、缓存
private LoadingCache<String, Optional<City>> cityNameCache = CacheBuilder.newBuilder().maximumSize(5000)
.expireAfterWrite(30, TimeUnit.MINUTES).build(new CacheLoader<String, Optional<City>>() {
@Override
public Optional<City> load(String cityName) {
return getCityByCityName(cityName);
}
});
public Optional<City> getCityByCityName(@Nullable String cityName) {
if (StringUtils.isBlank(cityName)) {
return Optional.absent();
}
try {
City city = cityService.getValidByCityName(cityName);
if (null != city && city.getId() > 0) {
return Optional.of(city);
}
} catch (Exception e) {
logger.error(e);
}
return Optional.absent();
}
