HBase Java客户端编程

时间:2023-01-12 08:30:28

本文以HBase 0.90.2为例,介绍如何在Windows系统,Eclipse IDE集成环境下,使用Java语言,进行HBase客户端编程,包含建立表、删除表、插入记录、删除记录、各种方式下的查询操作等。

1. 准备工作

1、下载后安装jdk包(这里使用的是jdk-6u10-rc2-bin-b32-windows-i586-p-12_sep_2008);

2、下载eclipse,解压到本地(这里使用的是eclipse-java-helios-SR2-win32);

3、下载HBase包,解压安装包到本地(这里使用的是hbase-0.90.2)。

2. 搭建开发环境

1、运行Eclipse,创建一个新的Java工程“HBaseClient”,右键项目根目录,选择 “Properties”->“Java Build Path”->“Library”->“Add External JARs”,将HBase解压后根目录下的hbase-0.90.2.jar、hbase-0.90.2-tests.jar和lib子目录下所有jar 包添加到本工程的Classpath下。

2、按照步骤1中的操作,将自己所连接的HBase的配置文件hbase-site.xml添加到本工程的Classpath中,如下所示为配置文件的一个示例:

 
 
 
  1. <configuration>
  2. <property>
  3. <name>hbase.rootdir</name>
  4. <value>hdfs://hostname:9000/hbase</value>
  5. </property>
  6. <property>
  7. <name>hbase.cluster.distributed</name>
  8. <value>true</value>
  9. </property>
  10. <property>
  11. <name>hbase.zookeeper.quorum</name>
  12. <value>*.*.*.*, *.*.*.*, *.*.*.*</value>
  13. </property>
  14. <property skipInDoc="true">
  15. <name>hbase.defaults.for.version</name>
  16. <value>0.90.2</value>
  17. </property>
  18. </configuration>

3、下面可以在Eclipse环境下进行HBase编程了。

3. HBase基本操作代码示例

3.1 初始化配置

1 privatestatic Configuration conf =null;
2 /**
3 * 初始化配置
4 */
5 static {
6 conf = HBaseConfiguration.create();
7 }

3.2 创建表

 
 
 
  1. /**
  2. * 创建表操作
  3. * @throws IOException
  4. */
  5. publicvoid createTable(String tablename, String[] cfs) throws IOException {
  6. HBaseAdmin admin =new HBaseAdmin(conf);
  7. if (admin.tableExists(tablename)) {
  8. System.out.println("表已经存在!");
  9. }
  10. else {
  11. HTableDescriptor tableDesc =new HTableDescriptor(tablename);
  12. for (int i =0; i < cfs.length; i++) {
  13. tableDesc.addFamily(new HColumnDescriptor(cfs[i]));
  14. }
  15. admin.createTable(tableDesc);
  16. System.out.println("表创建成功!");
  17. }
  18. }

3.3 删除表

 1 /**
2 * 删除表操作
3 * @param tablename
4 * @throws IOException
5 */
6 publicvoid deleteTable(String tablename) throws IOException {
7 try {
8 HBaseAdmin admin =new HBaseAdmin(conf);
9 admin.disableTable(tablename);
10 admin.deleteTable(tablename);
11 System.out.println("表删除成功!");
12 } catch (MasterNotRunningException e) {
13 e.printStackTrace();
14 } catch (ZooKeeperConnectionException e) {
15 e.printStackTrace();
16 }
17 }

3.4 插入一行记录

 
 
 
  1. /**
  2. * 插入一行记录
  3. * @param tablename
  4. * @param cfs
  5. */
  6. publicvoid writeRow(String tablename, String[] cfs) {
  7. try {
  8. HTable table =new HTable(conf, tablename);
  9. Put put =new Put(Bytes.toBytes("rows1"));
  10. for (int j =0; j < cfs.length; j++) {
  11. put.add(Bytes.toBytes(cfs[j]),
  12. Bytes.toBytes(String.valueOf(1)),
  13. Bytes.toBytes("value_1"));
  14. table.put(put);
  15. }
  16. } catch (IOException e) {
  17. e.printStackTrace();
  18. }
  19. }

3.5 删除一行记录

 1 /**
2 * 删除一行记录
3 * @param tablename
4 * @param rowkey
5 * @throws IOException
6 */
7 publicvoid deleteRow(String tablename, String rowkey) throws IOException {
8 HTable table =new HTable(conf, tablename);
9 List list =new ArrayList();
10 Delete d1 =new Delete(rowkey.getBytes());
11 list.add(d1);
12 table.delete(list);
13 System.out.println("删除行成功!");
14 }

3.6 查找一行记录

 
 
 
  1. /**
  2. * 查找一行记录
  3. * @param tablename
  4. * @param rowkey
  5. */
  6. publicstaticvoid selectRow(String tablename, String rowKey)
  7. throws IOException {
  8. HTable table =new HTable(conf, tablename);
  9. Get g =new Get(rowKey.getBytes());
  10. Result rs = table.get(g);
  11. for (KeyValue kv : rs.raw()) {
  12. System.out.print(new String(kv.getRow()) +"");
  13. System.out.print(new String(kv.getFamily()) +":");
  14. System.out.print(new String(kv.getQualifier()) +"");
  15. System.out.print(kv.getTimestamp() +"");
  16. System.out.println(new String(kv.getValue()));
  17. }
  18. }

3.7 查询表中所有行

 1 /**
2 * 查询表中所有行
3 * @param tablename
4 */
5 publicvoid scaner(String tablename) {
6 try {
7 HTable table =new HTable(conf, tablename);
8 Scan s =new Scan();
9 ResultScanner rs = table.getScanner(s);
10 for (Result r : rs) {
11 KeyValue[] kv = r.raw();
12 for (int i =0; i < kv.length; i++) {
13 System.out.print(new String(kv[i].getRow()) +"");
14 System.out.print(new String(kv[i].getFamily()) +":");
15 System.out.print(new String(kv[i].getQualifier()) +"");
16 System.out.print(kv[i].getTimestamp() +"");
17 System.out.println(new String(kv[i].getValue()));
18 }
19 }
20 } catch (IOException e) {
21 e.printStackTrace();
22 }
23 }

 

转自:http://www.cnblogs.com/panfeng412/archive/2011/08/14/2137984.html

 

第二个例子

package com.hbase;

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.MasterNotRunningException;
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 HbaseClient {

	private static Configuration conf = null;
	    
	/**
	 * hbase-0.90.3
	 * 初始化配置
	 */
	static {
		conf = HBaseConfiguration.create();
		conf.set("hbase.master", "192.168.27.12");
	}

	/**
	 * 创建表操作
	 * 
	 * @throws IOException
	 */
	public void createTable(String tablename, String[] cfs) throws IOException {
		HBaseAdmin admin = new HBaseAdmin(conf);
		if (admin.tableExists(tablename)) {
			System.out.println("表已经存在!");
		} else {
			HTableDescriptor tableDesc = new HTableDescriptor(tablename);
			for (int i = 0; i < cfs.length; i++) {
				tableDesc.addFamily(new HColumnDescriptor(cfs[i]));
			}
			admin.createTable(tableDesc);
			System.out.println(" 表创建成功!");
		}
	}

	/**
	 * 删除表操作
	 * 
	 * @param tablename
	 * @throws IOException
	 */
	public void deleteTable(String tablename) throws IOException {
		try {
			HBaseAdmin admin = new HBaseAdmin(conf);
			if (!admin.tableExists(tablename)) {
				System.out.println("表不存在, 无需进行删除操作!");
			}else{
				admin.disableTable(tablename);
				admin.deleteTable(tablename);
				System.out.println(" 表删除成功!");
			}
		} catch (MasterNotRunningException e) {
			e.printStackTrace();
		} catch (ZooKeeperConnectionException e) {
			e.printStackTrace();
		}
	}

	public void insertRow() throws Exception{
         HTable table = new HTable(conf, "test");
         Put put = new Put(Bytes.toBytes("row3"));
         put.add(Bytes.toBytes("cf"), Bytes.toBytes("444"), Bytes.toBytes("value444"));
         table.put(put);
	}
	
	/**
	 * 插入一行记录
	 * 
	 * @param tablename
	 * @param cfs
	 */
	public void writeRow(String tablename, String[] cfs) {
		try {
			HTable table = new HTable(conf, tablename);
			Put put = new Put(Bytes.toBytes("rows3"));
			for (int j = 0; j < cfs.length; j++) {
				put.add(Bytes.toBytes(cfs[j]),
						Bytes.toBytes(cfs[j]+String.valueOf(1)),
						Bytes.toBytes(cfs[j]+"value"));
				
				table.put(put);
			}
			System.out.println("写入成功!");
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	//写多条记录
	public void writeMultRow(String tablename, String[][] cfs) {
		try {
			HTable table = new HTable(conf, tablename);
			List<Put> lists = new ArrayList<Put>();
			for (int i = 0; i < cfs.length; i++) {
				Put put = new Put(Bytes.toBytes(cfs[i][0]));
				put.add(Bytes.toBytes(cfs[i][1]),
						Bytes.toBytes(cfs[i][2]),
						Bytes.toBytes(cfs[i][3]));
				lists.add(put);
			}
			table.put(lists);
			System.out.println("写入成功!");
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	/**
	 * 删除一行记录
	 * 
	 * @param tablename
	 * @param rowkey
	 * @throws IOException
	 */
	public void deleteRow(String tablename, String rowkey) throws IOException {
		HTable table = new HTable(conf, tablename);
		List<Delete> list = new ArrayList<Delete>();
		Delete d1 = new Delete(rowkey.getBytes());
		list.add(d1);
		table.delete(list);
		System.out.println("删除行成功!");
	}

	/**
	 * 查找一行记录
	 * 
	 * @param tablename
	 * @param rowkey
	 */
	public static void selectRow(String tablename, String rowKey)
			throws IOException {
		HTable table = new HTable(conf, tablename);
		Get g = new Get(rowKey.getBytes());
//		g.addColumn(Bytes.toBytes("cf:1"));
		Result rs = table.get(g);
		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()));
		}
	}

	/**
	 * 查询表中所有行
	 * 
	 * @param tablename
	 */
	public void scaner(String tablename) {
		try {
			HTable table = new HTable(conf, tablename);
			Scan s = new Scan();
			ResultScanner rs = table.getScanner(s);
			for (Result r : rs) {
				KeyValue[] kv = r.raw();
				for (int i = 0; i < kv.length; i++) {
					System.out.print(new String(kv[i].getRow()) + "  ");
					System.out.print(new String(kv[i].getFamily()) + ":");
					System.out.print(new String(kv[i].getQualifier()) + "  ");
					System.out.print(kv[i].getTimestamp() + "  ");
					System.out.println(new String(kv[i].getValue()));
				}
			}
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	public static void main(String[] args) throws Exception {
		HbaseClient cli = new HbaseClient();
		
		//删除表
		cli.deleteTable("test");
		
		//创建表
		cli.createTable("test", new String[]{"cf"});
		
		
		//写多条记录
		cli.writeMultRow("test", new String[][]{{"rows1","cf","1","value1"},{"rows1","cf","2","value2"},{"rows2","cf","2","value2"}});
		
		//写一条记录
		cli.writeRow("test", new String[]{"cf"});

		System.out.println("\n查询一个rows1:");
		selectRow("test", "rows1");
		
		System.out.println("\n查询所有:");
		cli.scaner("test");
		
	}
}

转自: http://blog.csdn.net/renren000/article/details/6662595