我不能让批处理扫描仪只扫描特定的行,当设置启动和停止键到同一件事时,我没有得到任何条目,当使用扫描仪时,我得到了这个异常:
“java.lang.IllegalArgumentException:开始键必须小于范围内的结束键(测试:[] 0 false,测试:[] 0 false)”...
我在 Visual Studio 2010 中用 C# 编写,并在项目中使用 Thrift(版本 0.9.1.1)和 Accumulo(版本 1.5.0)proxy.thrift 代码。
这是我的代码,一切“正常”,但我没有得到任何条目client.nextK
class Program
{
static byte[] GetBytes(string str)
{
return Encoding.ASCII.GetBytes(str);
}
static string GetString(byte[] bytes)
{
return Encoding.ASCII.GetString(bytes);
}
static void Main(string[] args)
{
try
{
/** connect **/
TTransport transport = new TSocket("192.168.58.62", 42424);
transport = new TFramedTransport(transport);
TCompactProtocol protocol = new TCompactProtocol(transport);
transport.Open();
AccumuloProxy.Client client = new AccumuloProxy.Client(protocol);
Dictionary<string, string> passwd = new Dictionary<string,string>();
passwd.Add("password", "password");
var login = client.login("root", passwd);
/** connect end **/
/** Get all data from one "Row" **/
var bScanner = new BatchScanOptions();
Range range = new Range();
range.Start = new Key();
range.Start.Row = GetBytes("Test");
range.Stop = new Key();
range.Stop.Row = GetBytes("Test");
bScanner.Ranges = new List<Range>();
bScanner.Ranges.Add(range);
var scanId = client.createBatchScanner(login, "firstTable", bScanner);
var more = true;
while (more)
{
var scan = client.nextK(scanId, 10);
more = scan.More;
foreach (var entry in scan.Results)
{
Console.WriteLine("{0} {1}:{2} [{3}] {4}", GetString(entry.Key.Row), GetString(entry.Key.ColFamily), GetString(entry.Key.ColQualifier), GetString(entry.Key.ColVisibility), GetString(entry.Value));
}
}
client.closeScanner(scanId);
Console.WriteLine();
/** Get data end **/
}
catch (Exception e)
{
Console.WriteLine(e);
}
}
}
Accumulo 1.5 的用户手册显示了这个代码片段,这与我正在做的相同(但在 C# 中):(http://accumulo.apache.org/1.5/accumulo_user_manual.html#_basic_table)
Range r = new Range(userid, userid); // single row
Scanner s = conn.createScanner("userdata", auths);
s.setRange(r);
s.fetchColumnFamily(new Text("age"));
for(Entry<Key,Value> entry : s)
System.out.println(entry.getValue().toString());