HBase Java客户端编程

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HBase Java客户端编程

2013年02月09日 ⁄ 综合 ⁄ 共 8239字 ⁄ 字号小中大 ⁄ 评论关闭

文章目录

1. 准备工作
2. 搭建开发环境
3. HBase基本操作代码示例

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：

 <configuration>
 <property>
 <name>hbase.rootdir</name>
 <value>hdfs://hostname:9000/hbase</value>
 </property>
 <property>
 <name>hbase.cluster.distributed</name>
 <value>true</value>
 </property>
 <property>
 <name>hbase.zookeeper.quorum</name>
 <value>*.*.*.*, *.*.*.*, *.*.*.*</value>
 </property>
 <property skipInDoc="true">
 <name>hbase.defaults.for.version</name>
 <value>0.90.2</value>
 </property>
 </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

 /**
  * 创建表操作
  * @throws IOException
 */
 publicvoid 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！");
     }
 }

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

 /**
  * 插入一行记录
  * @param tablename
  * @param cfs
 */
 publicvoid writeRow(String tablename, String[] cfs) {
 try {
         HTable table =new HTable(conf, tablename);
         Put put =new Put(Bytes.toBytes("rows1"));
 for (int j =0; j < cfs.length; j++) {
             put.add(Bytes.toBytes(cfs[j]),
                     Bytes.toBytes(String.valueOf(1)),
                     Bytes.toBytes("value_1"));
             table.put(put);
         }
     } catch (IOException e) {
         e.printStackTrace();
     }
 }

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

 /**
  * 查找一行记录
  * @param tablename
  * @param rowkey
 */
 publicstaticvoid selectRow(String tablename, String rowKey)
 throws IOException {
     HTable table =new HTable(conf, tablename);
     Get g =new Get(rowKey.getBytes());
     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()));
     }
 }

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

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作者: chatty

该日志由 chatty 于11年前发表在综合分类下，最后更新于 2013年02月09日.
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