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Hbase 基本操作用 在java 上的实现,hbasejava

Hbase 基本操作用 在java 上的实现,hbasejava


点击有惊喜


1.首先确保hbase处于开启状态
2.创建maven 项目 导入依赖

<dependencies>
  
<dependency>
    <groupId>org.apache.hbasegroupId>
    <artifactId>hbase-clientartifactId>
    <version>1.2.0version>
dependency>
  
<dependency>
    <groupId>org.apache.hbasegroupId>
    <artifactId>hbase-serverartifactId>
    <version>1.2.0version>
dependency> 

3.在resources文件下添加两个文件
1.hbase-site.xml

  xml version="1.0"?>
xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<configuration>
        <property>
                <name>hbase.zookeeper.quorumname>
                <value>master,slave1,slave2value>
                <description>The directory shared by RegionServers.description>
        property>

        <property>
        <name>hbase.zookeeper.property.clientPortname>
        <value>2181value>
        property>
configuration>

2.log4j.properties
  # Global logging configuration
log4j.rootLogger=INFO, stdout
# MyBatis logging configuration...
log4j.logger.org 



.mybatis.example.BlogMapper=TRACE
# Console output...
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

4.实现基本操作

package com.test.bd17;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.NavigableMap;
import java.util.Random;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellScanner;
import org.apache.hadoop.hbase.CellUtil;
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;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.util.Bytes;


public class HbaseTest {
    public Connection connection;
    //用hbaseconfiguration初始化配置信息时会自动加载当前应用classpath下的hbase-site.xml
    public static Configuration configuration = HBaseConfiguration.create();
    public Table table;
    public Admin admin;

    public HbaseTest() throws Exception{
        //对connection初始化
        connection = ConnectionFactory.createConnection(configuration);
        admin = connection.getAdmin();
    }
    //创建表
    public void createTable(String tablename,String... cf1) throws Exception{
        //获取admin对象
        Admin admin = connection.getAdmin();
        //创建tablename对象描述表的名称信息
        TableName tname = TableName.valueOf(tablename);//bd17:mytable
        //创建HTableDescriptor对象,描述表信息
        HTableDescriptor tDescriptor = new HTableDescriptor(tname);
        //判断是否表已存在
        if(admin.tableExists(tname)){
            System.out.println("表"+tablename+"已存在");
            return;
        }
        //添加表列簇信息
        for(String cf:cf1){
            HColumnDescriptor famliy = new HColumnDescriptor(cf);
            tDescriptor.addFamily(famliy);
        }
        //调用admin的createtable方法创建表
        admin.createTable(tDescriptor);
        System.out.println("表"+tablename+"创建成功");
    }
    //删除表
    public void deleteTable(String tablename) throws Exception{
        Admin admin = connection.getAdmin();
        TableName tName = TableName.valueOf(tablename);
        if(admin.tableExists(tName)){
            admin.disableTable(tName);
            admin.deleteTable(tName);
            System.out.println("删除表"+tablename+"成功!");
        }else{
            System.out.println("表"+tablename+"不存在。");
        }
    }
    //新增数据到表里面Put
    public void putData() throws Exception{
        TableName tableName = TableName.valueOf("bd17:fromjava");
        Table table = connection.getTable(tableName);
        Random random = new Random();
        List batPut = new ArrayList();
        for(int i=0;i<10;i++){
            //构建put的参数是rowkey   rowkey_i (Bytes工具类,各种java基础数据类型和字节数组之间的相互转换)
            Put put = new Put(Bytes.toBytes("rowkey_"+i));
            put.addColumn(Bytes.toBytes("i"), Bytes.toBytes("username"), Bytes.toBytes("un_"+i));
            put.addColumn(Bytes.toBytes("i"), Bytes.toBytes("age"), Bytes.toBytes(random.nextInt(50)+1));
            put.addColumn(Bytes.toBytes("i"), Bytes.toBytes("birthday"), Bytes.toBytes("20170"+i+"01"));
            put.addColumn(Bytes.toBytes("j"), Bytes.toBytes("phone"), Bytes.toBytes("电话_"+i));
            put.addColumn(Bytes.toBytes("j"), Bytes.toBytes("email"), Bytes.toBytes("email_"+i));
            //单记录put
//          table.put(put);
            batPut.add(put);
        }
        table.put(batPut);
        System.out.println("表插入数据成功!");
    }
    public void getData() throws Exception{
        TableName tableName = TableName.valueOf("bd17:fromjava");
        table = connection.getTable(tableName);
        //构建get对象
        List gets = new ArrayList();
        for(int i=0;i<5;i++){
            Get get = new Get(Bytes.toBytes("rowkey_"+i));
            gets.add(get);
        }
        Result[] results = table.get(gets);
        for(Result result:results){
            //一行一行读取数据
//          NavigableMap<><>>> maps = result.getMap();
//          for(byte[] cf:maps.keySet()){
//              NavigableMap<>> valueWithColumnQualify = maps.get(cf);
//              for(byte[] columnQualify:valueWithColumnQualify.keySet()){
//                  NavigableMap valueWithTimeStamp = valueWithColumnQualify.get(columnQualify);
//                  for(Long ts:valueWithTimeStamp.keySet()){
//                      byte[] value = valueWithTimeStamp.get(ts);
//                      System.out.println("rowkey:"+Bytes.toString(result.getRow())+",columnFamliy:"+
//                              Bytes.toString(cf)+",comlumnQualify:"+Bytes.toString(columnQualify)+",timestamp:"
//                              +new Date(ts)+",value:"+Bytes.toString(value)
//                              );
//                  }
//              }
//          }

            //使用字段名称和列簇名称来获取value值
//          System.out.println("rowkey:"+Bytes.toString(result.getRow())+",columnfamily:i,columnqualify:username,value:"+
//                  Bytes.toString(result.getValue(Bytes.toBytes("i"), Bytes.toBytes("username")))
//                  );
//          System.out.println("rowkey:"+Bytes.toString(result.getRow())+",columnfamily:i,columnqualify:age,value:"+
//                  Bytes.toInt(result.getValue(Bytes.toBytes("i"), Bytes.toBytes("age")))
//                  );

            //使用cell获取result里面的数据
            CellScanner cellScanner = result.cellScanner();
            while(cellScanner.advance()){
                Cell cell = cellScanner.current();
                //从单元格cell中把数据获取并输出
                //使用 CellUtil工具类,从cell中把数据获取出来
                String famliy = Bytes.toString(CellUtil.cloneFamily(cell));
                String qualify = Bytes.toString(CellUtil.cloneQualifier(cell));
                String rowkey = Bytes.toString(CellUtil.cloneRow(cell));
                String value = Bytes.toString(CellUtil.cloneValue(cell));
                System.out.println("rowkey:"+rowkey+",columnfamily:"+famliy+",qualify:"+qualify+",value:"+value);
            }
        }
    }
    //关闭连接
    public void cleanUp() throws Exception{
        connection.close();
    }
    public static void main(String[] args) throws Exception {
        HbaseTest hbaseTest = new HbaseTest();
//      hbaseTest.createTable("bd17:fromjava", "i","j");
//      hbaseTest.deleteTable("bd17:fromjava");
//      hbaseTest.putData();
        hbaseTest.getData();
        hbaseTest.cleanUp();
    }
}

点击有惊喜


www.htsjk.Com true http://www.htsjk.com/hbase/36047.html NewsArticle Hbase 基本操作用 在java 上的实现,hbasejava 点击有惊喜 1.首先确保hbase处于开启状态 2.创建maven 项目 导入依赖 dependencies !-- https://mvnrepository.com/artifact/org.apache.hbase/hbase-client -- dependency g...
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