Java API 与HBase交互实例

HBase提供了Java API，可以通过API来实现对HBase的一些操作。

package hbase;

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

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
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;
import org.apache.hadoop.hbase.util.Bytes;

public class HBaseOperation {

	private Configuration config;
	private HBaseAdmin admin;

	public HBaseOperation() {
	}

	public HBaseOperation(Configuration config)
			throws MasterNotRunningException, ZooKeeperConnectionException,
			IOException {
		this.config = config;
		this.admin = new HBaseAdmin(config);
	}

	/**
	 * 创建表
	 * 
	 * @param tableName
	 *            表名
	 * @param family
	 *            列族名
	 */
	public void createTable(String tableName, String[] colFamilies)
			throws IOException {

		HTableDescriptor desc = new HTableDescriptor(
				TableName.valueOf(tableName));
		for (int i = 0; i < colFamilies.length; i++) {
			desc.addFamily(new HColumnDescriptor(colFamilies[i]));
		}
		if (this.admin.tableExists(tableName)) {
			System.out.println("table exists!");
			System.exit(0);
		} else {
			this.admin.createTable(desc);
			System.out.println("create table success!");
		}

	}

	/**
	 * 删除表
	 * 
	 * @param tableName
	 *            表名
	 */
	public void deleteTable(String tableName) throws IOException {
		if (this.admin.tableExists(tableName)) {
			admin.deleteTable(tableName);
			System.out.println("delete table success!");
		} else {
			System.out.println("table not exists!");
		}
	}

	/**
	 * 
	 * @param tableName
	 *            表名
	 * @param rowkey
	 *            行键
	 * @param family
	 *            列族名
	 * @param qualifier
	 *            列名
	 * @param value
	 *            列的值
	 */
	public void insertRecord(String tableName, String rowkey, String family,
			String qualifier, String value) throws IOException {
		HTable table = new HTable(config, tableName);// HTabel负责跟记录相关的操作如增删改查等
		Put put = new Put(Bytes.toBytes(rowkey));// 设置rowkey
		put.add(Bytes.toBytes(family), Bytes.toBytes(qualifier),
				Bytes.toBytes(value));// 将指定的列族中的某一列以及该列的值添加到put实例中
		table.put(put);
		System.out.println("insert record success！");
		table.close();
	}

	/**
	 * 根据rowkey查询某一行记录
	 * 
	 * @param tableName
	 *            表名
	 * @param rowkey
	 *            行键
	 * @return
	 */
	public Result getRecord(String tableName, String rowkey) throws IOException {
		HTable table = new HTable(config, tableName);

		Get get = new Get(Bytes.toBytes(rowkey));
		Result result = table.get(get);

		table.close();
		return result;
	}

	/**
	 * 查询某一列的值
	 * 
	 * @param tableName
	 *            表名
	 * @param rowkey
	 *            行键
	 * @param family
	 *            列族名
	 * @param qualifier
	 *            列名
	 */
	public Result getRecordByColumn(String tableName, String rowkey,
			String family, String qualifier) throws IOException {
		HTable table = new HTable(config, tableName);

		Get get = new Get(Bytes.toBytes(rowkey));
		get.addColumn(Bytes.toBytes(family), Bytes.toBytes(qualifier));
		Result result = table.get(get);

		table.close();
		return result;
	}

	/**
	 * 遍历查询所有记录
	 * 
	 * @param tableName
	 *            表名
	 */
	public List<Result> getAllRecord(String tableName) throws IOException {
		HTable table = new HTable(config, tableName);
		Scan scan = new Scan();
		ResultScanner scanner = table.getScanner(scan);
		List<Result> list = new ArrayList<Result>();
		for (Result result : scanner) {
			list.add(result);
		}
		table.close();
		return list;
	}

	/**
	 * 删除一行记录
	 * 
	 * @param tableName
	 *            表名
	 * @param rowkey
	 *            行键
	 */
	public void deleteRow(String tableName, String rowkey) throws IOException {
		HTable table = new HTable(config, tableName);

		Delete delete = new Delete(Bytes.toBytes(rowkey));
		table.delete(delete);

		System.out.println("row are deleted!");
		table.close();
	}

	public void deleteColumn(String tableName, String rowkey, String family,
			String qualifier) throws IOException {
		HTable table = new HTable(config, tableName);

		Delete delete = new Delete(Bytes.toBytes(rowkey));
		delete.deleteColumn(Bytes.toBytes(family), Bytes.toBytes(qualifier));
		table.delete(delete);

		System.out.println("clomun are deleted！");
		table.close();
	}
}

测试类：

package hbase;

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

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
import org.apache.hadoop.hbase.client.Result;

public class HBaseTest {
	public static void main(String[] args) throws MasterNotRunningException,
			ZooKeeperConnectionException, IOException {
		// 1.初始化HBaseOperation
		Configuration config = new Configuration();
		config.set("hbase.zookeeper.quorum", "H01,H02,H03");
		config.set("hbase.zookeeper.property.clientPort", "2181");
		HBaseOperation hbase = new HBaseOperation(config);

		// 2. 测试相应操作
		// 2.1 创建表
		String tableName = "blog";
		String colFamilies[] = { "article", "author" };
		hbase.createTable(tableName, colFamilies);

		// 2.2 插入一条记录
		hbase.insertRecord(tableName, "row1", "article", "title", "hadoop");
		hbase.insertRecord(tableName, "row1", "author", "name", "tom");
		hbase.insertRecord(tableName, "row1", "author", "nickname", "tt");

		// 2.2 查询一条记录
		Result rs1 = hbase.getRecord(tableName, "row1");
		for (Cell cell : rs1.rawCells()) {
			System.out.println(new String(cell.getRowArray()));
			System.out.println(new String(cell.getFamilyArray()));
			System.out.println(new String(cell.getQualifierArray()));
			System.out.println(new String(cell.getValueArray()));
		}

		// 2.3 查询所有记录
		List<Result> list = hbase.getAllRecord(tableName);
		Iterator<Result> it = list.iterator();
		while (it.hasNext()) {
			Result rs2 = it.next();
			for (Cell cell : rs2.rawCells()) {
				System.out.println("row key is : "
						+ new String(cell.getRowArray()));
				System.out.println("family is  : "
						+ new String(cell.getFamilyArray()));
				System.out.println("qualifier is:"
						+ new String(cell.getQualifierArray()));
				System.out.print("timestamp is:" + cell.getTimestamp());
				System.out.println("Value  is  : "
						+ new String(cell.getValueArray()));
			}
		}
		
		
	}
}