Hadoop——HBase配置、shell编程和api编程

disable 'student'
drop 'student'

package hbaseTest;

import java.io.IOException;

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.KeyValue;
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.Delete;
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.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.util.Bytes;

public class HbaseTest{
    // hadoop配置
    public static Configuration configuration;
    // hbase客户端连接
    public static Connection connection;
    //获取管理员权限
    public static Admin admin;

    //主函数中的语句请逐句执行，只需删除其前的//即可，如：执行insertRow时请将其他语句注释
    public static void main(String[] args)throws Exception{
        //创建一个表，表名为Score，列族为sname,course
//        createTable("Score",new String[]{"sname","course","age","sex"});
        //查看已有的表
//        listTables();
        //查看表的所有记录
//      selectAll("Score");

        //在Score表中插入一条数据，其行键为95001,sname为Mary（因为sname列族下没有子列所以第四个参数为空）
        //等价命令：put 'Score','95001','sname','Mary'
//        insertRow("Score", "95001", "sname", "", "Mary");
        //在Score表中插入一条数据，其行键为95001,course:Math为88（course为列族，Math为course下的子列）
        //等价命令：put 'Score','95001','score:Math','88'
//        insertRow("Score", "95001", "course", "Math", "88");
        //在Score表中插入一条数据，其行键为95001,course:English为85（course为列族，English为course下的子列）
        //等价命令：put 'Score','95001','score:English','85'
//        insertRow("Score", "95001", "course", "English", "85");

        //1、删除Score表中指定列数据，其行键为95001,列族为course，列为Math
        //执行这句代码前请deleteRow方法的定义中，将删除指定列数据的代码取消注释注释，将删除制定列族的代码注释
        //等价命令：delete 'Score','95001','score:Math'
        //deleteRow("Score", "95001", "course", "Math");

        //2、删除Score表中指定列族数据，其行键为95001,列族为course（95001的Math和English的值都会被删除）
        //执行这句代码前请deleteRow方法的定义中，将删除指定列数据的代码注释，将删除制定列族的代码取消注释
        //等价命令：delete 'Score','95001','score'
        //deleteRow("Score", "95001", "course", "");

        //3、删除Score表中指定行数据，其行键为95001
        //执行这句代码前请deleteRow方法的定义中，将删除指定列数据的代码注释，以及将删除制定列族的代码注释
        //等价命令：deleteall 'Score','95001'
//        deleteRow("Score", "95001", "", "");

        //查询Score表中，行键为95001，列族为course，列为Math的值
        getData("Score", "95001", "course", "Math");
        //查询Score表中，行键为95001，列族为sname的值（因为sname列族下没有子列所以第四个参数为空）
        getData("Score", "95001", "sname", "");

        //删除Score表
//        deleteTable("Score");
    }

    //建立连接
    public static void init(){
        configuration  = HBaseConfiguration.create();
        configuration.set("hbase.rootdir","hdfs://192.168.119.128:9000/hbase");
        configuration.set("hbase.zookeeper.quorum","192.168.119.128");  //hbase 服务地址
        configuration.set("hbase.zookeeper.property.clientPort","2181"); //端口号
        try{
            connection = ConnectionFactory.createConnection(configuration);
            admin = connection.getAdmin();
        }catch (IOException e){
            e.printStackTrace();
        }
    }
    //关闭连接
    public static void close(){
        try{
            if(admin != null){
                admin.close();
            }
            if(null != connection){
                connection.close();
            }
        }catch (IOException e){
            e.printStackTrace();
        }
    }


    /**
     * 建表。HBase的表中会有一个系统默认的属性作为主键，主键无需自行创建，默认为put命令操作中表名后第一个数据，因此此处无需创建id列
     * @param myTableName 表名
     * @param colFamily 列族名
     * @throws IOException
     */
    public static void createTable(String myTableName,String[] colFamily) throws IOException {

        init();
        TableName tableName = TableName.valueOf(myTableName);

        if(admin.tableExists(tableName)){
            System.out.println("talbe is exists!");
        }else {
            HTableDescriptor hTableDescriptor = new HTableDescriptor(tableName);
            for(String str:colFamily){
                HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(str);
                hTableDescriptor.addFamily(hColumnDescriptor);
            }
            admin.createTable(hTableDescriptor);
            System.out.println("create table success");
        }
        close();
    }
    /**
     * 删除指定表
     * @param tableName 表名
     * @throws IOException
     */
    public static void deleteTable(String tableName) throws IOException {
        init();
        TableName tn = TableName.valueOf(tableName);
        if (admin.tableExists(tn)) {
            admin.disableTable(tn);
            admin.deleteTable(tn);
        }
        close();
    }

    /**
     * 查看已有表
     * @throws IOException
     */
    public static void listTables() throws IOException {
        init();
        HTableDescriptor hTableDescriptors[] = admin.listTables();
        for(HTableDescriptor hTableDescriptor :hTableDescriptors){
            System.out.println(hTableDescriptor.getNameAsString());
        }
        close();
    }

    /**
     * 向某一行的某一列插入数据
     * @param tableName 表名
     * @param rowKey 行键
     * @param colFamily 列族名
     * @param col 列名（如果其列族下没有子列，此参数可为空）
     * @param val 值
     * @throws IOException
     */
    public static void insertRow(String tableName,String rowKey,String colFamily,String col,String val) throws IOException {
        init();
        Table table = connection.getTable(TableName.valueOf(tableName));
        Put put = new Put(rowKey.getBytes());
        put.addColumn(colFamily.getBytes(), col.getBytes(), val.getBytes());
        table.put(put);
        table.close();
        close();
    }

    /**
     * 删除数据
     * @param tableName 表名
     * @param rowKey 行键
     * @param colFamily 列族名
     * @param col 列名
     * @throws IOException
     */
    public static void deleteRow(String tableName,String rowKey,String colFamily,String col) throws IOException {
        init();
        Table table = connection.getTable(TableName.valueOf(tableName));
        Delete delete = new Delete(rowKey.getBytes());
        //删除指定列族的所有数据
        //delete.addFamily(colFamily.getBytes());
        //删除指定列的数据
        delete.addColumn(colFamily.getBytes(), col.getBytes());

        table.delete(delete);
        table.close();
        close();
    }
    /**
     * 根据行键rowkey查找数据
     * @param tableName 表名
     * @param rowKey 行键
     * @param colFamily 列族名
     * @param col 列名
     * @throws IOException
     */
    public static void getData(String tableName,String rowKey,String colFamily,String col)throws  IOException{
        init();
        Table table = connection.getTable(TableName.valueOf(tableName));
        Get get = new Get(rowKey.getBytes());
        get.addColumn(colFamily.getBytes(),col.getBytes());
        Result result = table.get(get);
        showCell(result);
        table.close();
        close();
    }
    /**
     * 格式化输出
     * @param result
     */
    public static void showCell(Result result){
        Cell[] cells = result.rawCells();
        for(Cell cell:cells){
            System.out.println("RowName:"+new String(CellUtil.cloneRow(cell))+" ");
            System.out.println("Timetamp:"+cell.getTimestamp()+" ");
            System.out.println("column Family:"+new String(CellUtil.cloneFamily(cell))+" ");
            System.out.println("row Name:"+new String(CellUtil.cloneQualifier(cell))+" ");
            System.out.println("value:"+new String(CellUtil.cloneValue(cell))+" ");
        }
    }
   //查询表中所有记录
    @SuppressWarnings("deprecation")
    public static void selectAll(String tableName) throws Exception{
        Table hTable = connection.getTable(TableName.valueOf(tableName));
        Scan scan = new Scan();
        ResultScanner resultScanner = null;
        try {
            resultScanner = hTable.getScanner(scan);
            for (Result result : resultScanner){
                for(KeyValue keyValue :result.raw()){
                    StringBuilder sb = new StringBuilder();
                    sb.append(Bytes.toString(keyValue.getRow())).append("\t");
                    sb.append(Bytes.toString(keyValue.getFamily())).append("\t");
                    sb.append(Bytes.toString(keyValue.getQualifier())).append("\t");
                    sb.append(keyValue.getTimestamp()).append("\t");
                    sb.append(Bytes.toString(keyValue.getValue())).append("\t");
                    System.out.println(sb.toString());
                }
            }
        } catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }finally {
            if (resultScanner != null)
            {
                 resultScanner.close();
            }
            System.out.println("selectAll end");
        }      

    }


}