HBase 列的详细解析

 
 
import java.io.IOException;
import java.util.List;
 
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.HColumnDescriptor;
import org.apache.hadoop.hbase.HTableDescriptor;
import org.apache.hadoop.hbase.MasterNotRunningException;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
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 HbaseDemo {
    static Configuration hbaseConfiguration = HBaseConfiguration.create();
    static{
        hbaseConfiguration.addResource("hbase-site.xml");
    }
     
    /**
     * 创建表
     * @param tablename 表名
     * @param columnFamily 列族
     * @throws IOException 
     * @throws ZooKeeperConnectionException 
     * @throws MasterNotRunningException 
     */
    public static void CreateTable(String tablename,String columnFamily) throws MasterNotRunningException, ZooKeeperConnectionException, IOException{
        HBaseAdmin admin = new HBaseAdmin(hbaseConfiguration);
        if(admin.tableExists(tablename)){//如果表已经存在
            System.out.println(tablename+"表已经存在!");
        }else{
            TableName tableName =TableName.valueOf(tablename);
            HTableDescriptor tableDesc = new HTableDescriptor(tableName);
            tableDesc.addFamily(new HColumnDescriptor(columnFamily));
            admin.createTable(tableDesc);
            System.out.println(tablename+"表已经成功创建!");
        }
    }
     
    /**
     * 向表中插入一条新数据
     * @param tableName 表名
     * @param row 行键key
     * @param columnFamily 列族
     * @param column 列名
     * @param data 要插入的数据
     * @throws IOException 
     */
    public static void PutData(String tableName,String row,String columnFamily,String column,String data) throws IOException{
        HTable table = new HTable(hbaseConfiguration, tableName);
        Put put = new Put(Bytes.toBytes(row));
        put.add(Bytes.toBytes(columnFamily), Bytes.toBytes(column), Bytes.toBytes(data));
        table.put(put);
        System.out.println("put '"+row+"','"+columnFamily+":"+column+"','"+data+"'");
    }
     
    /**
     * 获取指定行的所有数据
     * @param tableName 表名
     * @param row 行键key
     * @param columnFamily 列族
     * @param column 列名
     * @throws IOException 
     */
    public static void GetData(String tableName,String row,String columnFamily,String column) throws IOException{
         HTable table = new HTable(hbaseConfiguration, tableName);
        // Scan scan = new Scan();
        // ResultScanner  result = table.getScanner(scan);
         Get get = new Get(Bytes.toBytes(row));
         Result result = table.get(get);
         byte[] rb = result.getValue(Bytes.toBytes(columnFamily), Bytes.toBytes(column));
         String value = new String(rb,"UTF-8");
         System.out.println(value);
    }
     
    /**
     * 获取指定表的所有数据
     * @param tableName 表名
     * @throws IOException 
     */
    public static void ScanAll(String tableName) throws IOException{
         HTable table = new HTable(hbaseConfiguration, tableName);
         Scan scan = new Scan();
         ResultScanner resultScanner = table.getScanner(scan);
         for (Result result : resultScanner) {
             List<Cell> cells= result.listCells();
             for (Cell cell : cells) {
                 byte[] rb = cell.getValueArray();
                 String row = new String(result.getRow(),"UTF-8");
                 String family = new String(CellUtil.cloneFamily(cell),"UTF-8");
                 String qualifier = new String(CellUtil.cloneQualifier(cell),"UTF-8");
                 String value = new String(CellUtil.cloneValue(cell),"UTF-8");
                 System.out.println("[row:"+row+"],[family:"+family+"],[qualifier:"+qualifier+"],[value:"+value+"]");
            }
        }
    }
     
    /**
     * @param args
     */
    public static void main(String[] args) {
        try {
            //HbaseDemo.CreateTable("userinfo", "baseinfo");
            //HbaseDemo.PutData("userinfo", "row2", "baseinfo", "vio2", "驾驶车辆违法信息2：");
            //HbaseDemo.GetData("userinfo", "row2","baseinfo","vio2");
            HbaseDemo.ScanAll("userinfo");
            HbaseDemo.ScanAll("userinfo");
        } catch (Exception e) {
            e.printStackTrace();
        }
         
    }
 
}