HBase API java二次开发

几个重要HBase API类和数据模型之间的对应关系

java类	HBase数据模型
HBaseAdmin HBaseConfiguration	数据库
HTable	表（Table）
HTableDescriptor	列表（CF）
Put Get Scanner	列表修饰符

1.HBaseAdmin
作用：提供了一个接口来管理HBase数据库表信息，它提供的方法包括：创建表，删除表，列出表，使表有效或无效以及添加或删除列祖或成员等

函数	描述
addColumn	向一个已经存在的表中添加列
checkHBaseAvailable	静态函数，查看Hbase是否处于运行状态
createTable	创建一个表，同步操作
deleteTable	删除一个已经存在的表
enableTable	使表处于有效状态
disableTable	使表处于无效状态
listTables()	列出所有用户控件表项
modifyTable	修改表的模式，使异步的操作，可能需要花费一定的时间
tableExists	检查表是否存在

2.HBaseConfiguration
作用：对HBase进行配置
3.HTableDescriptor
作用：包含了表的名字及其对应的表的列族
4.HColumDescriptor
作用：维护着关于列祖的信息，例如版本号，压缩设置等，通常在创建表或者为表添加列族的时候使用

代码实现

package Hbase;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.*;
import org.apache.hadoop.hbase.util.Bytes;

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


public class hbasedemo {
    private Configuration conf;
    private Connection conn;
    private Admin hbAdmin;

    public void init() throws Exception{
        conf=new Configuration();
        conf.set("hbase.zookeeper.quorum","node01:2181,node02:2181,node03:2181");

//        conf= HBaseConfiguration.create();
        conn= ConnectionFactory.createConnection(conf);
        hbAdmin=conn.getAdmin();//创建表首先要创建一个Admin对象，然后让它来创建一张表

    }
    /**
     *
     * 表是否已经存在
     *
     */
    public void testExists() throws IOException{
        System.out.println(hbAdmin.tableExists(TableName.valueOf("mytest")));
    }

    /**
     * hbase表的创建
     */
    public void creat() throws IOException{
        TableName tablename= TableName.valueOf("mytest");//定义表名
        if (!hbAdmin.tableExists(tablename)){
            HTableDescriptor tabledesc = new HTableDescriptor(tablename);//定义表对象
            HColumnDescriptor familyDesc1 =new HColumnDescriptor(Bytes.toBytes("info1"));//定义列族对象
            HColumnDescriptor familyDesc2 =new HColumnDescriptor(Bytes.toBytes("info2"));
            familyDesc1.setMaxVersions(3);//设置数据保存的最大保存数
            tabledesc.addFamily(familyDesc1);//添加
            tabledesc.addFamily(familyDesc2);
            hbAdmin.createTable(tabledesc);//创建表

        } else {

        }

    }

    /**
     *
     * 禁用表
     */
    public void testdisable() throws IOException{
        TableName tablename =TableName.valueOf("mytest");
        hbAdmin.disableTable(tablename);
    }
    public void testIsDisable()throws IOException{
        TableName tablename =TableName.valueOf("mytest");
        System.out.println(hbAdmin.isTableDisabled(tablename));
    }
    public void testdrop()throws IOException{
        TableName tablename = TableName.valueOf("mytest");
        hbAdmin.deleteTable(tablename);
    }

    /**
     *一次增加一个单元格
     */
    public void testput()throws IOException {
        TableName tablename = TableName.valueOf("mytest");
        Table table = conn.getTable(tablename);
        Put put = new Put(Bytes.toBytes("aa"));//定义行
        put.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("name"), Bytes.toBytes("zhangfei"));
        table.put(put);
    }




    /**
     * 一次增加多个单元格
     */
    public void testputbatch()throws IOException {
        TableName tablename = TableName.valueOf("mytest");
        Table table = conn.getTable(tablename);
        List<Put> list = new ArrayList<>();
        Put put1 = new Put(Bytes.toBytes("aa"));
        put1.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("name"), Bytes.toBytes("guanYu"));
        Put put2 = new Put(Bytes.toBytes("aa"));
        put2.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("age"), Bytes.toBytes("20"));
        Put put3 = new Put(Bytes.toBytes("aa"));
        put3.addColumn(Bytes.toBytes("info2"), Bytes.toBytes("name"), Bytes.toBytes("liuBei"));
        Put put4 = new Put(Bytes.toBytes("aa"));
        put4.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("otherName"), Bytes.toBytes("guan2"));


        list.add(put1);
        list.add(put2);
        list.add(put3);
        list.add(put4);
        table.put(list);
    }
    /**
     * 删除一个单元格
     */
    public void testDelete() throws IOException{
        TableName tablename=TableName.valueOf("mytest");
        Table table =conn.getTable(tablename);
        Delete delete =new Delete(Bytes.toBytes("aa"));
        delete.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("otherName"));
        table.delete(delete);
    }
    /**
     * 查询一行数据(一个rowKey对应的数据),hbase shell中get操作
     * @throws IOException
     */

    public void testGet() throws IOException {
        TableName tableName = TableName.valueOf("mytest");
        Table table = conn.getTable(tableName);
        Get get = new Get(Bytes.toBytes("aa"));//指定行键
//		get.addColumn(Bytes.toBytes("info1"), Bytes.toBytes("name"));
        get.addFamily(Bytes.toBytes("info1"));//指定列族
        Result result = table.get(get);

        for(Cell cell : result.rawCells()) {
            System.out.print("行键:"+ Bytes.toString(CellUtil.cloneRow(cell))+"\t");
            System.out.print("列族:"+ Bytes.toString(CellUtil.cloneFamily(cell))+"\t");
            System.out.print("列标识:"+ Bytes.toString(CellUtil.cloneQualifier(cell))+"\t");
            System.out.println("值:"+ Bytes.toString(CellUtil.cloneValue(cell)));
        }
    }

    /**
     *扫描表中的数据
     * 
     */
    
    public void testscan() throws IOException{
        TableName tableName = TableName.valueOf("mytest");
        Table table = conn.getTable(tableName);
        Scan scan =new Scan();//得到用于扫描region的对象
        ResultScanner rs = table.getScanner(scan);//使用Htable得到resultscanner实现类的对象
        this.showResult(rs);
    }

    private void showResult(ResultScanner rs) {
        for(Result result : rs) {
            Cell[] cells = result.rawCells();

            for(Cell cell : cells) {
                System.out.print("rowkey:" + Bytes.toString(CellUtil.cloneRow(cell))+"\t");
                System.out.print("family:" + Bytes.toString(CellUtil.cloneFamily(cell))+"\t");
                System.out.print("qualifier:" + Bytes.toString(CellUtil.cloneQualifier(cell))+"\t");
                System.out.println("value:" + Bytes.toString(CellUtil.cloneValue(cell)));
            }
        }
    }

    /*
    * 行键过滤器扫描
    * */
    public  void testfilterscan() throws IOException{
        TableName tableName =TableName.valueOf("mytest");
        Table table = conn.getTable(tableName);
        Scan scan =new Scan();
        //正则表达式匹配
        Filter filter = new RowFilter(CompareFilter.CompareOp.EQUAL,new RegexStringComparator("^\\[a-z][0-9]$"));
        scan.setFilter(filter);
        this.showResult(table.getScanner(scan));

    }

    /*
    *
    * 列族过滤器*/
    public void testFamilyFilterScan() throws IOException {
        TableName tableName = TableName.valueOf("test001");
        Table table = conn.getTable(tableName);
        Scan scan = new Scan();
        scan.addFamily(Bytes.toBytes("info1"));

        Filter filter = new FamilyFilter(
                CompareFilter.CompareOp.EQUAL,
                new BinaryComparator(Bytes.toBytes("info2"))
        );
        scan.setFilter(filter);

        this.showResult(table.getScanner(scan));
    }

    /*
    *
    * 列标识过滤器*/
    public void testQualifierFilterScan() throws IOException {
        TableName tableName = TableName.valueOf("test001");
        Table table = conn.getTable(tableName);
        Scan scan = new Scan();

        Filter filter = new QualifierFilter(
                CompareFilter.CompareOp.EQUAL,
                new RegexStringComparator("^\\w*m\\w*$")
        );
        scan.setFilter(filter);

        this.showResult(table.getScanner(scan));
    }


    /*
    *
    * 值过滤器 ，对所有列族下所有列的值进行过滤*/
    public void testValueFilterScan() throws IOException {
        TableName tableName = TableName.valueOf("test001");
        Table table = conn.getTable(tableName);
        Scan scan = new Scan();
        scan.setStartRow(Bytes.toBytes("info1"));//指定开始键值

//		Filter filter = new ValueFilter(
//				CompareOp.EQUAL,
//				new RegexStringComparator("^\\d+")
//				);
        Filter filter = new ValueFilter(
                CompareFilter.CompareOp.EQUAL,
                new SubstringComparator("100")
        );
        scan.setFilter(filter);

        this.showResult(table.getScanner(scan));
    }





    public static void main(String[] args) throws Exception {
        System.setProperty("hadoop.home.dir", "E:\\hadoop-2.6.5\\");
        hbasedemo testa=new hbasedemo();
        testa.init();//抛出异常  alt+enter

        testa.creat();
        testa.testputbatch();
//        testa.testGet();
        testa.testscan();



    }







}