实验三：熟悉常用的HBase操作

实验环境：
(1)操作系统：linux(建议 ubuntu 16.04 或 Ubuntu 18.04)。
(2)hadoop 版本：3.1.3。
(3)HBase 版本：2.2.2。
(4)jdk 版本：1.8。
(5)Java IDE: Eclipse。
实验内容与完成情况：
(1)现有以下关系数据库中的表和数据(见表14-3〜表14-5),要求将其转换为适合于
HBase存储的表并插入数据。


在这里插入图片描述

（1）学生Student表
创建表的HBase shell命令语句如下：

第二行数据

第三行数据

（2）课程Course表
创建表的HBase Shell命令语句如下：

（3）选课表
创建表的HBase Shell命令语句如下：

(2)编程实现以下功能。
①createTable(String tableName, String]] fields)。
创建表，参数tableName 表的名称，字符串数组fields *存储记录各字段名的数组。 要求当HBase已经存在名为tableName的表时，先删除原有的表，再创建新的表。
Java代码：

package com.xusheng.HBase.shiyan31;import org.apache.hadoop.conf.Configuration;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.*;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;public class CreateTable {    public static Configuration configuration;    public static Connection connection;    public static Admin admin;    public static void createTable(String tableName,String[] fields) throws IOException {        init();        TableName tablename = TableName.valueOf(tableName);        if(admin.tableExists(tablename)){            System.out.println("table is exists!");            admin.disableTable(tablename);            admin.deleteTable(tablename);//删除原来的表        }        TableDescriptorBuilder tableDescriptor = TableDescriptorBuilder.newBuilder(tablename);        for(String str : fields){            tableDescriptor.setColumnFamily(ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes(str)).build());            admin.createTable(tableDescriptor.build());        }        close();    }    //建立连接    public static void init() {        configuration = HBaseConfiguration.create();        //configuration.set("hbase.rootdir", "hdfs://hadoop102:8020/HBase");        configuration.set("hbase.ZooKeeper.quorum","hadoop102,hadoop103,hadoop104");        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();        }    }    public static void main(String[] args) {        String[] fields = {"Score"};        try {            createTable("person", fields);        } catch (IOException e) {            e.printStackTrace();        }    }}

结果：

②addRecord(String tableName, String row, String]] fields, String口 values) 。
向表tableName、行row(用S_Name表示)和字符串数组fields指定的单元格中添加对 应的数据valueso其中,fields中每个元素如果对应的列族下还有相应的列限定符，用 “columnFamily： column"表示。例如，同时向MathComputerEnglish三列添加成绩时，字 符串数组 fields 为( “Score： Math” ," Score: Computer" , “Score： English” ｝，数组 values 存储 这三门课的成绩。

Java代码：

package com.xusheng.HBase.shiyan31;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.TableName;import org.apache.hadoop.hbase.client.*;import java.io.IOException;public class addRecord {    public static Configuration configuration;    public static Connection connection;    public static Admin admin;    public static void addRecord(String tableName, String row, String[] fields, String[] values) throws IOException {        init();        Table table = connection.getTable(TableName.valueOf(tableName));        for (int i = 0; i != fields.length; i++) {            Put put = new Put(row.getBytes());            String[] cols = fields[i].split(":");            put.addColumn(cols[0].getBytes(), cols[1].getBytes(), values[i].getBytes());            table.put(put);        }        table.close();        close();    }    public static void init() {        configuration = HBaseConfiguration.create();        //configuration.set("hbase.rootdir", "hdfs://hadoop102:8020/HBase");        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");        try {            connection = ConnectionFactory.createConnection(configuration);            admin = connection.getAdmin();        } catch (IOException e) {            e.printStackTrace();        }    }    public static void close() {        try {            if (admin != null) {                admin.close();            }            if (null != connection) {                connection.close();            }        } catch (IOException e) {            e.printStackTrace();        }    }    public static void main(String[] args) {        String[] fields = {"Score:Math", "Score:Computer Science", "Score:English"};        String[] values = {"99", "80", "100"};        try {            addRecord("tableName", "Score", fields, values);        } catch (IOException e) {            e.printStackTrace();        }    }}

结果：

③scanColumn(String tableName, String column) 。
浏览表tableName某列的数据，如果某行记录中该列数据不存在，则返回null。要求 当参数column为某列族名时，如果底下有若干个列限定符，则要列出每个列限定符代表 的列的数据；当参数column为某列具体名(例如“ Score: Math")时，只需要列出该列的 数据。

Java代码：

package com.xusheng.HBase.shiyan31;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.TableName;import org.apache.hadoop.hbase.client.*;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;public class scanColumn {    public static Configuration configuration;    public static Connection connection;    public static Admin admin;    public static void scanColumn(String tableName, String column) throws IOException {        init();        Table table = connection.getTable(TableName.valueOf(tableName));        Scan scan = new Scan();        scan.addFamily(Bytes.toBytes(column));        ResultScanner scanner = table.getScanner(scan);        for (Result result = scanner.next(); result != null; result = scanner.next()) {            showCell(result);        }        table.close();        close();    }    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)) + " ");        }    }    public static void init() {        configuration = HBaseConfiguration.create();        //configuration.set("hbase.rootdir", "hdfs://hadoop102:8020/HBase");        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");        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();        }    }    public static void main(String[] args) {        try {            scanColumn("tableName", "Score");        } catch (IOException e) {            e.printStackTrace();        }    }}

结果：

④modifyData(String tableName, String row, String column) 。
修改表tableName,即修改行row(可以用学生姓名S_Name表示)、列column指定的 单元格的数据。

Java代码：

package com.xusheng.HBase.shiyan31;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.Cell;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.TableName;import org.apache.hadoop.hbase.client.*;import java.io.IOException;public class modifyData {    public static long ts;    public static Configuration configuration;    public static Connection connection;    public static Admin admin;    public static void modifyData(String tableName, String row, String column, String val) throws IOException {        init();        Table table = connection.getTable(TableName.valueOf(tableName));        Put put = new Put(row.getBytes());        Scan scan = new Scan();        ResultScanner resultScanner = table.getScanner(scan);        for (Result r : resultScanner) {            for (Cell cell : r.getColumnCells(row.getBytes(), column.getBytes())) {                ts = cell.getTimestamp();            }        }        put.addColumn(row.getBytes(), column.getBytes(), ts, val.getBytes());        table.put(put);        table.close();        close();    }    public static void init() {        configuration = HBaseConfiguration.create();        //configuration.set("hbase.rootdir", "hdfs://hadoop102:8020/HBase");        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");        try {            connection = ConnectionFactory.createConnection(configuration);            admin = connection.getAdmin();        } catch (IOException e) {            e.printStackTrace();        }    }    public static void close() {        try {            if (admin != null) {                admin.close();            }            if (null != connection) {                connection.close();            }        } catch (IOException e) {            e.printStackTrace();        }    }    public static void main(String[] args) {        try {            modifyData("tableName", "Score", "Math", "100");        } catch (IOException e) {            e.printStackTrace();        }    }}

结果：

⑤deleteRow(String tableName, String row)。
删除表tableName中row指定的行的记录。

Java代码：

package com.xusheng.HBase.shiyan31;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.Cell;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.TableName;import org.apache.hadoop.hbase.client.*;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;public class deleteRow {    public static long ts;    public static Configuration configuration;    public static Connection connection;    public static Admin admin;    public static void deleteRow(String tableName, String row) throws IOException {        init();        Table table = connection.getTable(TableName.valueOf(tableName));        Delete delete=new Delete(row.getBytes());        table.delete(delete);        table.close();        close();    }    public static void init() {        configuration = HBaseConfiguration.create();        //configuration.set("hbase.rootdir", "hdfs://hadoop102:8020/HBase");        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");        try {            connection = ConnectionFactory.createConnection(configuration);            admin = connection.getAdmin();        } catch (IOException e) {            e.printStackTrace();        }    }    public static void close() {        try {            if (admin != null) {                admin.close();            }            if (null != connection) {                connection.close();            }        } catch (IOException e) {            e.printStackTrace();        }    }    public static void main(String[] args) {        try {            deleteRow("tableName", "Score");        } catch (IOException e) {            e.printStackTrace();        }    }}

结果：

来源地址：https://blog.csdn.net/m0_52014276/article/details/130874212