dubbo-cluster/src/main/java/org/apache/dubbo/rpc/cluster/loadbalance/
ConsistentHashLoadBalance.java
![image](https://user-images.githubusercontent.com/30815149/55045041-740f4980-5077-11e9-8b6c-7a2b18b0d58e.png)
我看其他地方都是用Constants进行替换，这里是不是可以使用Constants类里的属性进行替换
public static final String ENVIRONMENT = "environment";
    /**
     * Test environment key.
     */
    public static final String TEST_ENVIRONMENT = "test";
    /**
     * Development environment key.
     */
    public static final String DEVELOPMENT_ENVIRONMENT = "develop";
    /**
     * Production environment key.
     */
    public static final String PRODUCTION_ENVIRONMENT = "product";
    public static final String ETCD3_NOTIFY_MAXTHREADS_KEYS = "etcd3.notify.maxthreads";
    public static final int DEFAULT_ETCD3_NOTIFY_THREADS = DEFAULT_IO_THREADS;
    public static final String DEFAULT_ETCD3_NOTIFY_QUEUES_KEY = "etcd3.notify.queues";
    public static final int DEFAULT_GRPC_QUEUES = 300_0000;
    /**
     * metrics
     */
    public static final String DUBBO_PROVIDER = "dubbo.provider";
    public static final String DUBBO_CONSUMER = "dubbo.consumer";
    public static final String DUBBO_PROVIDER_METHOD = "dubbo.provider.method";
    public static final String DUBBO_CONSUMER_METHOD = "dubbo.consumer.method";
    public static final String SERVICE = "service";
    public static final String METHOD = "method";
    public static final String DUBBO_GROUP = "dubbo";
    public static final String METRICS_KEY = "metrics";
}