使用
RichAsyncFunction 加 CacheBuilder
CacheBuilder.newBuilder()
//最多存储10000条
.maximumSize(10000)
//过期时间为1分钟
.expireAfterWrite(60, TimeUnit.SECONDS)
.build();
public class LRU extends RichAsyncFunction<String,Order> {
private static final Logger LOGGER = LoggerFactory.getLogger(LRU.class);
String table = "info";
Cache<String, String> cache = null;
private HBaseClient client = null;
@Override
public void open(Configuration parameters) throws Exception {
super.open(parameters);
//创建hbase客户端
client = new HBaseClient("127.0.0.1","7071");
cache = CacheBuilder.newBuilder()
//最多存储10000条
.maximumSize(10000)
//过期时间为1分钟
.expireAfterWrite(60, TimeUnit.SECONDS)
.build();
}
@Override
public void asyncInvoke(String input, ResultFuture<Order> resultFuture) throws Exception {
JSONObject jsonObject = JSONObject.parseObject(input);
Integer cityId = jsonObject.getInteger("city_id");
String userName = jsonObject.getString("user_name");
String items = jsonObject.getString("items");
//读缓存
String cacheCityName = cache.getIfPresent(cityId);
//如果缓存获取失败再从hbase获取维度数据
if(cacheCityName != null){
Order order = new Order();
order.setCityId(cityId);
order.setItems(items);
order.setUserName(userName);
order.setCityName(cacheCityName);
resultFuture.complete(Collections.singleton(order));
}else {
client.get(new GetRequest(table,String.valueOf(cityId))).addCallback((Callback<String, ArrayList<KeyValue>>) arg -> {
for (KeyValue kv : arg) {
String value = new String(kv.value());
Order order = new Order();
order.setCityId(cityId);
order.setItems(items);
order.setUserName(userName);
order.setCityName(value);
resultFuture.complete(Collections.singleton(order));
cache.put(String.valueOf(cityId), value);
}
return null;
});
}
}
}