Java在HBase数据库创建表

作者：chszs，版权所有，未经同意，不得转载。博主主页：http://blog.csdn.net/chszs

要通过Java在Hbase中创建一个数据表，首先需要导入hbase-client.jar驱动包。可以在项目pom.xml配置文件中添加依赖：

org.apache.hbase

hbase-client

1.1.0.1

在添加依赖后，我们需要创建Configuration对象，并指定core-site.xml和hbase-site.xml作为资源文件。

Configuration config = HBaseConfiguration.create();

config.addResource(new Path("/etc/hbase/conf/hbase-site.xml"));

config.addResource(new Path("/etc/hadoop/conf/core-site.xml"));

还需要在Configuration对象中设置hbase.zookeeper.quorum参数和hbase.zookeeper.property.clientPort参数的值，这些值也可以在hbase-site.xml配置文件中找到：

Configuration config = HBaseConfiguration.create();

config.set("hbase.zookeeper.quorum", "127.0.0.1");

config.set("hbase.zookeeper.property.clientPort", "2181");

Configuration对象创建完成后，接着创建连接到HBase数据库的Connection对象，并通过此对象获取Admin对象，它负责实现创建数据表的操作：

Connection connection = ConnectionFactory.createConnection(config);

Admin admin = connection.getAdmin();

一旦创建了Admin对象后，可以通过下面的代码创建数据表了：

String tableName = "users";

if (!admin.isTableAvailable(TableName.valueOf(tableName))) {

HTableDescriptor hbaseTable = new HTableDescriptor(TableName.valueOf(tableName));

hbaseTable.addFamily(new HColumnDescriptor("name"));

hbaseTable.addFamily(new HColumnDescriptor("contact_info"));

hbaseTable.addFamily(new HColumnDescriptor("personal_info"));

admin.createTable(hbaseTable);

}

会严重是否存在“users”名的数据表，如果此表不存在就会创建一个新表，列名包括：家庭名、联系信息和个人信息。

完整的程序如下：

package com.wordpress.khodeprasad;

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.TableName;

import org.apache.hadoop.hbase.client.Admin;

import org.apache.hadoop.hbase.client.Connection;

import org.apache.hadoop.hbase.client.ConnectionFactory;

/**

* @author Prasad Khode

*

*/

public class CreateTable {

public static void main(String[] args) {

CreateTable object = new CreateTable();

object.createTable();

}

public void createTable() {

Configuration config = HBaseConfiguration.create();

config.set("hbase.zookeeper.quorum", "127.0.0.1");

config.set("hbase.zookeeper.property.clientPort", "2181");

Connection connection = null;

Admin admin = null;

try {

connection = ConnectionFactory.createConnection(config);

admin = connection.getAdmin();

String tableName = "users";

if (!admin.isTableAvailable(TableName.valueOf(tableName))) {

HTableDescriptor hbaseTable = new HTableDescriptor(TableName.valueOf(tableName));

hbaseTable.addFamily(new HColumnDescriptor("name"));

hbaseTable.addFamily(new HColumnDescriptor("contact_info"));

hbaseTable.addFamily(new HColumnDescriptor("personal_info"));

admin.createTable(hbaseTable);

}

} catch (Exception e) {

e.printStackTrace();

} finally {

try {

if (admin != null) {

admin.close();

}

if (connection != null && !connection.isClosed()) {

connection.close();

}

} catch (Exception e2) {

e2.printStackTrace();

}

}

}

}