架构师训练营第五周作业

package connsistent;



import java.util.ArrayList;
import java.util.List;
import java.util.TreeMap;

public class ConsistentHash {
    TreeMap<Integer, Cache> map = new TreeMap<>();
    List<Cache> servers = new ArrayList<>();

    public ConsistentHash(List<Cache> servers) {
        this.servers = servers;
    }

    public void addServers(String[] servers, int virtualNo) {
        if (servers != null) {
            for (String server : servers) {
                Cache cacheServer = (Cache) new CacheServer(server);
                map.put(hashCode(server), cacheServer);
                for (int i = 1; i <= virtualNo; i++) {
                    map.put(getVirutalHashCode(server, i), cacheServer);
                }

                this.servers.add(cacheServer);
            }
        }
    }

    private int getVirutalHashCode(String key, int i) {
        key = key + "&&Virtual" + i;
        return hashCode(key);
    }

    public static int hashCode(String key) {
        final int p = 16777619;
        int ret = (int) 2166136261L;
        for (int i = 0; i < key.length(); i++) {
            ret = (ret ^ key.charAt(i)) * p;
        }
        ret += ret << 13;
        ret ^= ret >> 7;
        ret += ret << 3;
        ret ^= ret >> 17;
        ret += ret << 5;

        return ret < 0 ? -ret : ret;
    }

}



package connsistent;

import cn.beinet.Cache;

import java.util.HashMap;
import java.util.Map;

 
public class CacheServer implements Cache {
    private Map<String, String> caches = new HashMap<>();

    private String serverName;

    public CacheServer(String serverName) {
        this.serverName = serverName;
    }

    public String getServerName() {
        return serverName;
    }

    public Map<String, String> getCaches() {
        return caches;
    }

    @Override
    public String get(String key) {
        return caches.get(key);
    }

    @Override
    public void set(String key, String val) {
        caches.put(key, val);
    }
}


package connsistent;

public interface Cache {

    String get(String key);

    void set(String key, String val);
}