Connection connection = ConnectionFactory.createConnection(conf);

try {
    Table table = connection.getTable(TableName.valueOf("tablename”));
    // 插入数据
    Put put = new Put(Bytes.toBytes("row"));
    put.addColumn(Bytes.toBytes("family"), Bytes.toBytes("qualifier"), Bytes.toBytes("value"));
    table.put(put);
    // 单行读取
    Get get = new Get(Bytes.toBytes("row"));
    Result res = table.get(get);
    // 删除一行数据
    Delete delete = new Delete(Bytes.toBytes("row"));
    table.delete(delete);
}catch (IOException e) {
     //.....       
} finally {
    table.close();
    connection.close();     
}

protected final PoolMap<ConnectionId, T> connections;

//….

this.connections = new PoolMap<>(getPoolType(conf), getPoolSize(conf));

public class ConnectionManager {
    private Map<String, Connection> connectionMap = new ConcurrentHashMap<>();

    public Connection getConnection(String resourceId, Configuration configuration) {
        ResourceInfo resourceInfo = ResourceInfoCache.getResourceInfoByCache(resourceId);
        if (resourceInfo == null) {
            throw new IllegalArgumentException("error resourceid: " + resourceId);
        }
        String key = getClusterKey(resourceInfo);
        if (connectionMap.containsKey(key)) {
            return connectionMap.get(key);
        }
        synchronized (this) {
            //DCL检查
            if (connectionMap.containsKey(key)) {
                return connectionMap.get(key);
            }
            Connection connection = null;
            try {
                connection = ConnectionFactory.createConnection(configuration);
            } catch (IOException e) {
                return null;
            }
            connectionMap.put(key, connection);
            return connection;
        }
    }

    @PreDestroy
    public void doDestroy() {
        for (Map.Entry<String, Connection> entry : connectionMap.entrySet()) {
            Connection connection = entry.getValue();
            if (connection != null) {
               try {
                    connection.close();
                } catch (IOException e) {
                    //。。。。
                }
            }
        }
    }
}