Hbase基本操作示例

Hadoop Hbase通过行关键字、列（列族名：列名）和时间戳的三元组确定一个存储单元（cell），即由

{row key, column family, column name, timestamp} 可以唯一确定一个存储值，即一个键值对：

{row key, column family, column name, timestamp} -> value

下面演示了Hbase的基本操作。包括

1、创建表

2、删除表

3、添加记录

4、删除记录

5、查询记录等

忘记的时候可以过来看看。

import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HBaseAdmin;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;

public class HBaseOperation {

	// 相关属性
	private Configuration conf;
	private HBaseAdmin admin;

	public HBaseOperation(Configuration conf) throws IOException {
		this.conf = HBaseConfiguration.create(conf);
		this.conf.set("hbase.zookeeper.quorum", "namenode");
		this.conf.set("hbase.zookeeper.property.clientPort", "2181");
		this.admin = new HBaseAdmin(this.conf);
	}

	public HBaseOperation() throws IOException {
		Configuration cnf = new Configuration();
		this.conf = HBaseConfiguration.create(cnf);
		this.conf.set("hbase.zookeeper.quorum", "namenode");
		this.conf.set("hbase.zookeeper.property.clientPort", "2181");
		this.admin = new HBaseAdmin(this.conf);
	}

	/**
	 * 创建表
	 * @param tableName		表名
	 * @param colFamilies	<span style="white-space:pre">	</span>列族
	 * @throws IOException
	 */
	public void createTable(String tableName, String colFamilies[])
			throws IOException {

		if (this.admin.tableExists(tableName)) { // 表已经存在
			System.out.println("Table: " + tableName + " already exists !");
			this.admin.deleteTable(tableName); // 删除表
		}

		HTableDescriptor dsc = new HTableDescriptor(tableName); // 新建表描述
		int len = colFamilies.length;
		for (int i = 0; i < len; i++) {
			HColumnDescriptor family = new HColumnDescriptor(colFamilies[i]);
			dsc.addFamily(family); // 在表描述中添加列族
		}
		admin.createTable(dsc); // 创建表
		System.out.println("create table " + tableName + " ok.");
	}

	/**
	 * 删除一张表
	 * @param tableName
	 * @throws IOException
	 */
	public void deleteTable(String tableName) throws IOException {
		if (this.admin.tableExists(tableName)) {
			admin.disableTable(tableName);
			admin.deleteTable(tableName);
			System.out.println("delete table " + tableName + " ok.");
		} else {
			System.out.println("Table Not Exists !");
		}
	}

	/**
	 * 添加记录
	 * @param tableName	 表名字
	 * @param rowkey 	 行关键字
	 * @param family  	 列族
	 * @param qualifier 列名
	 * @param value		值
	 * @throws IOException
	 */
	public void insertRecord(String tableName, String rowkey, String family,
			String qualifier, String value) throws IOException {

		HTable table = new HTable(this.conf, tableName);
		Put put = new Put(rowkey.getBytes());
		put.add(family.getBytes(), qualifier.getBytes(), value.getBytes());
		table.put(put);

		System.out.println("insert recored " + rowkey + " to table "
				+ tableName + " ok.");
		table.close();
	}

	/**
	 * 添加一组记录
	 * @param tableName
	 * @param putList
	 * @throws IOException
	 */
	public void insertRecordList(String tableName, List<Put> putList)
			throws IOException {
		HTable table = new HTable(this.conf, tableName);

		for (int i = 0; i < putList.size(); i++) {
			Put put = putList.get(i);
			table.put(put);
		}
		putList.clear();
		table.close();
	}

	/**
	 * 删除一行数据
	 * @param tableName	表名
	 * @param rowkey	行关键字
	 * @throws IOException
	 */
	public void deleteRecord(String tableName, String rowkey)
			throws IOException {

		HTable table = new HTable(this.conf, tableName);
		Delete del = new Delete(rowkey.getBytes());
		table.delete(del);
		System.out.println("del recored " + rowkey + " ok.");
		table.close();
	}

	/**
	 * 获取一条记录
	 * @param tableName	表名
	 * @param rowkey	行关键字
	 * @return
	 * @throws IOException
	 */
	public Result getOneRecord(String tableName, String rowkey)
			throws IOException {
		HTable table = new HTable(this.conf, tableName);
		Get get = new Get(rowkey.getBytes());		//get对象
		Result rs = table.get(get);
		for (KeyValue kv : rs.raw()) {
			System.out.print(new String(kv.getRow()) + " ");
			System.out.print(new String(kv.getFamily()) + ":");
			System.out.print(new String(kv.getQualifier()) + " ");
			System.out.print(kv.getTimestamp() + " ");
			System.out.println(new String(kv.getValue()));
		}
		table.close();
		return rs;
	}

	/**
	 * 获取一张表的所有数据
	 * @param tableName
	 * @return
	 * @throws IOException
	 */
	public List<Result> getAllRecord(String tableName) throws IOException {

		HTable table = new HTable(this.conf, tableName);
		Scan scan = new Scan();			//Scan对象
		ResultScanner scanner = table.getScanner(scan);
		List<Result> list = new ArrayList<Result>();
		for (Result r : scanner) {
			list.add(r);
		}
		scanner.close();
		table.close();

		for (Result r : scanner) {
			for (KeyValue kv : r.raw()) {
				System.out.print(new String(kv.getRow()) + " ");
				System.out.print(new String(kv.getFamily()) + ":");
				System.out.print(new String(kv.getQualifier()) + " ");
				System.out.print(kv.getTimestamp() + " ");
				System.out.println(new String(kv.getValue()));
			}
		}
		return list;
	}
}