private static boolean reload_all() {
   // 载入新的配置
   ConfigInitializer loader = new ConfigInitializer(true);
   Map<String, UserConfig> users = loader.getUsers();
   Map<String, SchemaConfig> schemas = loader.getSchemas();
   Map<String, PhysicalDBNode> dataNodes = loader.getDataNodes();
   Map<String, PhysicalDBPool> dataHosts = loader.getDataHosts();
   CloudbCluster cluster = loader.getCluster();
   QuarantineConfig quarantine = loader.getQuarantine();
   // 应用新配置
   CloudbConfig conf = CloudbServer.getInstance().getConfig();
   conf.setDataNodes(dataNodes);
   Map<String, PhysicalDBPool> cNodes = conf.getDataHosts();
   boolean reloadStatus = true;
   for (PhysicalDBPool dn : dataHosts.values()) {
     dn.setSchemas(
         CloudbServer.getInstance().getConfig().getDataNodeSchemasOfDataHost(dn.getHostName()));
     // init datahost
     String index = DnPropertyUtil.loadDnIndexProps().getProperty(dn.getHostName(), "0");
     if (!"0".equals(index)) {
       LOGGER.info("init datahost: " + dn.getHostName() + "  to use datasource index:" + index);
     }
     dn.init(Integer.valueOf(index));
     // dn.init(0);
     if (!dn.isInitSuccess()) {
       reloadStatus = false;
       break;
     }
   }
   // 如果重载不成功,则清理已初始化的资源。
   if (!reloadStatus) {
     LOGGER.warn("reload failed ,clear previously created datasources ");
     for (PhysicalDBPool dn : dataHosts.values()) {
       dn.clearDataSources("reload config");
       dn.stopHeartbeat();
     }
     return false;
   }
   // 应用重载
   conf.reload(users, schemas, dataNodes, dataHosts, cluster, quarantine, true);
   // 处理旧的资源
   for (PhysicalDBPool dn : cNodes.values()) {
     dn.clearDataSources("reload config clear old datasources");
     dn.stopHeartbeat();
   }
   // 清理缓存
   CloudbServer.getInstance().getCacheService().clearCache();
   return true;
 }
 private static Set<String> getTableSet(ServerConnection c, Map<String, String> parm) {
   TreeSet<String> tableSet = new TreeSet<String>();
   CloudbConfig conf = CloudbServer.getInstance().getConfig();
   Map<String, UserConfig> users = conf.getUsers();
   UserConfig user = users == null ? null : users.get(c.getUser());
   if (user != null) {
     Map<String, SchemaConfig> schemas = conf.getSchemas();
     for (String name : schemas.keySet()) {
       if (null != parm.get(SCHEMA_KEY)
           && parm.get(SCHEMA_KEY).toUpperCase().equals(name.toUpperCase())) {
         if (null == parm.get("LIKE_KEY")) {
           tableSet.addAll(schemas.get(name).getTables().keySet());
         } else {
           String p = "^" + parm.get("LIKE_KEY").replaceAll("%", ".*");
           Pattern pattern = Pattern.compile(p, Pattern.CASE_INSENSITIVE);
           Matcher ma;
           for (String tname : schemas.get(name).getTables().keySet()) {
             ma = pattern.matcher(tname);
             if (ma.matches()) {
               tableSet.add(tname);
             }
           }
         }
       }
     }
     ;
   }
   return tableSet;
 }
 private static boolean reload() {
   // 载入新的配置
   ConfigInitializer loader = new ConfigInitializer(false);
   Map<String, UserConfig> users = loader.getUsers();
   Map<String, SchemaConfig> schemas = loader.getSchemas();
   Map<String, PhysicalDBNode> dataNodes = loader.getDataNodes();
   Map<String, PhysicalDBPool> dataHosts = loader.getDataHosts();
   CloudbCluster cluster = loader.getCluster();
   QuarantineConfig quarantine = loader.getQuarantine();
   // 应用新配置
   CloudbServer instance = CloudbServer.getInstance();
   CloudbConfig conf = instance.getConfig();
   // 应用重载
   conf.reload(users, schemas, dataNodes, dataHosts, cluster, quarantine, false);
   // 清理缓存
   instance.getCacheService().clearCache();
   return true;
 }
 public static void execute(ManagerConnection c, final boolean loadAll) {
   final ReentrantLock lock = CloudbServer.getInstance().getConfig().getLock();
   lock.lock();
   try {
     ListenableFuture<Boolean> listenableFuture =
         CloudbServer.getInstance()
             .getListeningExecutorService()
             .submit(
                 new Callable<Boolean>() {
                   @Override
                   public Boolean call() throws Exception {
                     return loadAll ? reload_all() : reload();
                   }
                 });
     Futures.addCallback(
         listenableFuture,
         new ReloadCallBack(c),
         CloudbServer.getInstance().getListeningExecutorService());
   } finally {
     lock.unlock();
   }
 }
 /**
  * response method.
  *
  * @param c
  */
 public static void response(ServerConnection c, String stmt, int type) {
   String showSchemal = SchemaUtil.parseShowTableSchema(stmt);
   String cSchema = showSchemal == null ? c.getSchema() : showSchemal;
   SchemaConfig schema = CloudbServer.getInstance().getConfig().getSchemas().get(cSchema);
   if (schema != null) {
     // 不分库的schema,show tables从后端 mysql中查
     String node = schema.getDataNode();
     if (!Strings.isNullOrEmpty(node)) {
       c.execute(stmt, ServerParse.SHOW, null);
       return;
     }
   } else {
     c.writeErrMessage(ErrorCode.ER_NO_DB_ERROR, "No database selected");
   }
   // 分库的schema,直接从SchemaConfig中获取所有表名
   Map<String, String> parm = buildFields(c, stmt);
   java.util.Set<String> tableSet = getTableSet(c, parm);
   int i = 0;
   byte packetId = 0;
   header.packetId = ++packetId;
   fields[i] =
       PacketUtil.getField("Tables in " + parm.get(SCHEMA_KEY), Fields.FIELD_TYPE_VAR_STRING);
   fields[i++].packetId = ++packetId;
   eof.packetId = ++packetId;
   ByteBuffer buffer = c.allocate();
   // write header
   buffer = header.write(buffer, c, true);
   // write fields
   for (FieldPacket field : fields) {
     buffer = field.write(buffer, c, true);
   }
   // write eof
   buffer = eof.write(buffer, c, true);
   // write rows
   packetId = eof.packetId;
   for (String name : tableSet) {
     RowDataPacket row = new RowDataPacket(FIELD_COUNT);
     row.add(StringUtil.encode(name.toLowerCase(), c.getCharset()));
     row.packetId = ++packetId;
     buffer = row.write(buffer, c, true);
   }
   // write last eof
   EOFPacket lastEof = new EOFPacket();
   lastEof.packetId = ++packetId;
   buffer = lastEof.write(buffer, c, true);
   // post write
   c.write(buffer);
 }
 /**
  * 从全局的schema列表中查询指定的schema是否存在, 如果存在则替换connection属性中原有的schema, 如果不存在,则throws
  * SQLNonTransientException,表示指定的schema 不存在
  *
  * @param sysConfig
  * @param schema
  * @param sqlType
  * @param realSQL
  * @param charset
  * @param info
  * @param cachePool
  * @param hintSQLValue
  * @return
  * @throws SQLNonTransientException
  */
 @Override
 public RouteResultset route(
     SystemConfig sysConfig,
     SchemaConfig schema,
     int sqlType,
     String realSQL,
     String charset,
     ServerConnection sc,
     LayerCachePool cachePool,
     String hintSQLValue)
     throws SQLNonTransientException {
   SchemaConfig tempSchema = CloudbServer.getInstance().getConfig().getSchemas().get(hintSQLValue);
   if (tempSchema != null) {
     return routeStrategy.route(
         sysConfig, tempSchema, sqlType, realSQL, charset, sc, cachePool, null);
   } else {
     String msg = "can't find hint schema:" + hintSQLValue;
     LOGGER.warn(msg);
     throw new SQLNonTransientException(msg);
   }
 }