HBase 的一个典型例子
1、例子一
import java.io.IOException;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Scanner;
import org.apache.hadoop.hbase.io.BatchUpdate;
import org.apache.hadoop.hbase.io.Cell;
import org.apache.hadoop.hbase.io.RowResult;
public class MyClient {
public static void main(String args[]) throws IOException {
// You need a configuration object to tell the client where to connect.
// But don't worry, the defaults are pulled from the local config file.
HBaseConfiguration config = new HBaseConfiguration();
// This instantiates an HTable object that connects you to the "myTable"
// table.
HTable table = new HTable(config, "myTable");
// To do any sort of update on a row, you use an instance of the BatchUpdate
// class. A BatchUpdate takes a row and optionally a timestamp which your
// updates will affect.
BatchUpdate batchUpdate = new BatchUpdate("myRow");
// The BatchUpdate#put method takes a Text that describes what cell you want
// to put a value into, and a byte array that is the value you want to
// store. Note that if you want to store strings, you have to getBytes()
// from the string for HBase to understand how to store it. (The same goes
// for primitives like ints and longs and user-defined classes - you must
// find a way to reduce it to bytes.)
batchUpdate.put("myColumnFamily:columnQualifier1",
"columnQualifier1 value!".getBytes());
// Deletes are batch operations in HBase as well.
batchUpdate.delete("myColumnFamily:cellIWantDeleted");
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