HBase-----JAVA API

package com.bpf.hbase;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.client.Delete;
import org.apache.hadoop.hbase.client.Get;
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;
import org.apache.hadoop.io.IOUtils;

/* 
 * CRUD
 * */
@SuppressWarnings("deprecation")
public class HBaseOperation {
    
    public static  HTable getHtableByTablename(String tableName) throws Exception {
        Configuration conf = HBaseConfiguration.create();
            
        //get table instance
        HTable table = new HTable(conf, tableName);
        
        return table;
        
    }
    
    public static void getData() throws Exception {
        
        String tableName = "user";
        HTable table = getHtableByTablename(tableName);
        
        //create Get with rowkey
        Get get = new Get(Bytes.toBytes("1001"));
        
        //add column
        get.addColumn(Bytes.toBytes("info"), Bytes.toBytes("name"));
        get.addColumn(Bytes.toBytes("info"), Bytes.toBytes("age"));
        
        //get data
        Result result = table.get(get);
        Cell[] cells = result.rawCells();
        for (Cell cell : cells) {
            System.out.println(      
                Bytes.toString(CellUtil.cloneFamily(cell)) + ":" + 
                Bytes.toString(CellUtil.cloneQualifier(cell)) + ":" + 
                Bytes.toString(CellUtil.cloneValue(cell))                          
            );
        }
        
        table.close();  
    }
    
    public static void putData() throws Exception {
     
        String tableName = "user";
        HTable table = getHtableByTablename(tableName);
     
        // put data
        Put put = new Put(Bytes.toBytes("1003"));
        //add columns
        put.add(Bytes.toBytes("info"), Bytes.toBytes("name"), Bytes.toBytes("calvin"));
        put.add(Bytes.toBytes("info"), Bytes.toBytes("age"), Bytes.toBytes(25));
        put.add(Bytes.toBytes("info"), Bytes.toBytes("address"), Bytes.toBytes("UK"));
        
        table.put(put);
        table.close();

    }
    
    public static void deleteData() throws Exception {
        
        String tableName = "user";
        HTable table = getHtableByTablename(tableName);

        Delete delete = new Delete(Bytes.toBytes("1003"));
        
        //刪除某列
        //列有多版本，deleteColumn刪除最新的版本 deleteColumns刪除所有版本
        //delete.deleteColumn(Bytes.toBytes("info"), Bytes.toBytes("address"));
        
        //刪除整行(一個列族一個列族刪)
        delete.deleteFamily(Bytes.toBytes("info"));
        
        table.delete(delete);
        table.close();
    }
    
    public static void scanData() {

        
        String tableName = "user";
        HTable table = null;
        ResultScanner scanner = null;
        try {
            
            table = getHtableByTablename(tableName);
            Scan scan = new Scan();
            
            //range 
            scan.setStartRow(Bytes.toBytes("1001"));
            scan.setStopRow(Bytes.toBytes("1002"));
            //也可以在實例化時構造函數中指定
            //Scan scan2 = new Scan(startRow, stopRow);
            
            //添加scan的條件
            //scan.addFamily(family);
            //scan.addColumn(family, qualifier)
            
            //filter---->PageFilter分頁,PrefixFilter前綴            
            //scan.setFilter(filter)
            
            //scan.setCacheBlocks(cacheBlocks);
            //scan.setCaching(caching);
            
            
            scanner = table.getScanner(scan);
            for (Result result : scanner) {
                System.out.println(Bytes.toString(result.getRow()));
                System.out.println(result);
                System.out.println("----------------------------");
                
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } finally {
            IOUtils.closeStream(scanner);
            IOUtils.closeStream(table);
        }
    
    }

    public static void main(String[] args) {
        
    }
}