jredis分片选择数据库且支持服务器故障动态过滤

1 JedisShardInfo 默认不支持选择数据库

扩展后的代码

package redis.clients.jedis.ext;import redis.clients.jedis.Jedis;import redis.clients.jedis.JedisShardInfo;public class JedisDBShardInfo extends JedisShardInfo {    private int database;    public JedisDBShardInfo(String host,int database) {super(host, 6379);this.database=database;}public JedisDBShardInfo(String host, String name,int database) {super(host, 6379, name);this.database=database;}public JedisDBShardInfo(String host, int port,int database) {super(host, port, 2000);this.database=database;}public JedisDBShardInfo(String host, int port, String name,int database) {super(host, port, 2000, name);this.database=database;}public JedisDBShardInfo(String host, int port, int timeout,int database) {super(host, port, timeout, 1);this.database=database;}public JedisDBShardInfo(String host, int port, int timeout, String name,int database) {super(host, port, timeout, name);this.database=database;}public Jedis createResource() {Jedis jedis=new Jedis(this);try {if (this.database != 0&&jedis.ping().equals("PONG")) {jedis.select(this.database);return jedis;}} catch (Exception e) {System.out.println("连接异常=>"+getHost()+":"+getPort()+":"+getDatabase());//e.printStackTrace();}return null;}public int getDatabase() {return database;}public void setDatabase(int database) {this.database = database;}}

2 目前发现，当分片的时候，只要其中一台服务器出现问题，导致所有的分片jedis都无法使用，没法实现动态的将故障服务器暂时的过滤到，修改了源代码

package redis.clients.util; import java.util.ArrayList;import java.util.Collection;import java.util.Collections;import java.util.LinkedHashMap;import java.util.List;import java.util.Map;import java.util.TreeMap;import java.util.regex.Matcher;import java.util.regex.Pattern; public class Sharded<R, S extends ShardInfo<R>> {     public static final int DEFAULT_WEIGHT = 1;    private TreeMap<Long, S> nodes;    private final Hashing algo;    private final Map<ShardInfo<R>, R> resources = new LinkedHashMap<ShardInfo<R>, R>();     /**     * The default pattern used for extracting a key tag. The pattern must have     * a group (between parenthesis), which delimits the tag to be hashed. A     * null pattern avoids applying the regular expression for each lookup,     * improving performance a little bit is key tags aren't being used.     */    private Pattern tagPattern = null;    // the tag is anything between {}    public static final Pattern DEFAULT_KEY_TAG_PATTERN = Pattern            .compile("\\{(.+?)\\}");     public Sharded(List<S> shards) {        this(shards, Hashing.MURMUR_HASH); // MD5 is really not good as we works        // with 64-bits not 128    }     public Sharded(List<S> shards, Hashing algo) {        this.algo = algo;        initialize(shards);    }     public Sharded(List<S> shards, Pattern tagPattern) {        this(shards, Hashing.MURMUR_HASH, tagPattern); // MD5 is really not good        // as we works with        // 64-bits not 128    }     public Sharded(List<S> shards, Hashing algo, Pattern tagPattern) {        this.algo = algo;        this.tagPattern = tagPattern;        initialize(shards);    }     private void initialize(List<S> shards) {        nodes = new TreeMap<Long, S>();         for (int i = 0; i != shards.size(); ++i) {            final S shardInfo = shards.get(i);   <span style="color:#999999;">   </span><span style="color:#ff9966;">      //增加动态的 结合分片扩展          R r=shardInfo.createResource();          if(r!=null){          if (shardInfo.getName() == null){                  for (int n = 0; n < 128 * shardInfo.getWeight(); n++) {                    nodes.put(this.algo.hash("SHARD-" + i + "-NODE-" + n), shardInfo);                  }                }               else{                  for (int n = 0; n < 128 * shardInfo.getWeight(); n++) {                    nodes.put(this.algo.hash(shardInfo.getName() + ":" + n), shardInfo);                  }               }                resources.put(shardInfo,r);          }        }</span>    }    public R getShard(byte[] key) {        return resources.get(getShardInfo(key));    }     public R getShard(String key) {        return resources.get(getShardInfo(key));    }     public S getShardInfo(byte[] keyBytes) {      //$this->initialize();      //$ringKeys = $this->_ringKeys;             Long key = this.algo.hash(keyBytes);             List<Long> keys = new ArrayList<Long>();      keys.addAll(nodes.keySet());      int upper = keys.size() - 1;      int lower = 0;       while (lower <= upper) {          int index = (lower + upper) >> 1;          Long item  = keys.get(index);          if (item > key) {              upper = index - 1;          }          else if (item < key) {              lower = index + 1;          }          else {              return nodes.get(item);          }      }      return nodes.get(keys.get(wrapAroundStrategy(upper, lower, keys.size())));     }         protected int wrapAroundStrategy(int upper, int lower, int ringKeysCount) {          return upper >= 0 ? upper : ringKeysCount - 1;    }     public S getShardInfo(String key) {        return getShardInfo(SafeEncoder.encode(getKeyTag(key)));    }     /**     * A key tag is a special pattern inside a key that, if preset, is the only     * part of the key hashed in order to select the server for this key.     *     * @see http://code.google.com/p/redis/wiki/FAQ#I     *      'm_using_some_form_of_key_hashing_for_partitioning,_but_wh     * @param key     * @return The tag if it exists, or the original key     */    public String getKeyTag(String key) {        if (tagPattern != null) {            Matcher m = tagPattern.matcher(key);            if (m.find())                return m.group(1);        }        return key;    }     public Collection<S> getAllShardInfo() {        return Collections.unmodifiableCollection(nodes.values());    }     public Collection<R> getAllShards() {        return Collections.unmodifiableCollection(resources.values());    }}