使用hbase Java api完成以下操作： 1.建表userfollower 2.用户Mary有一个粉丝Alice，Alice关注列表中也存在Mary 3.用户Jack有两个粉丝Bob和Ben 4.Jack还关注了Mary 5.查看Jack被哪些人关注，Jack关注了谁 6.Bob取关了Jack 7.扫描全表数据 导入以下包完成import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.;import org.apache.hadoop.hbase.client.;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;使用Table table = connection.getTable(TableName.valueOf(tableName));创建表

代码如下：

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
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.util.Bytes;
import java.io.IOException;

public class HBaseExample {
    private static Configuration conf = null;
    private static Connection connection = null;

    static {
        conf = HBaseConfiguration.create();
        try {
            connection = ConnectionFactory.createConnection(conf);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) throws IOException {
        String tableName = "userfollower";
        createTable(tableName);

        addUserFollower("Mary", "Alice");
        addUserFollower("Jack", "Bob");
        addUserFollower("Jack", "Ben");
        addUserFollower("Jack", "Mary");

        System.out.println("Jack is followed by: " + getFollowers("Jack"));
        System.out.println("Jack follows: " + getFollowed("Jack"));

        removeUserFollower("Bob", "Jack");

        scanTable(tableName);
    }

    private static void createTable(String tableName) throws IOException {
        Admin admin = connection.getAdmin();
        TableName table = TableName.valueOf(tableName);
        if (!admin.tableExists(table)) {
            TableDescriptorBuilder tableDescriptorBuilder = TableDescriptorBuilder.newBuilder(table);
            ColumnFamilyDescriptor columnFamilyDescriptor = ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("cf")).build();
            tableDescriptorBuilder.setColumnFamily(columnFamilyDescriptor);
            admin.createTable(tableDescriptorBuilder.build());
        }
    }

    private static void addUserFollower(String user, String follower) throws IOException {
        Table table = connection.getTable(TableName.valueOf("userfollower"));
        Put put = new Put(Bytes.toBytes(user));
        put.addColumn(Bytes.toBytes("cf"), Bytes.toBytes("follower"), Bytes.toBytes(follower));
        table.put(put);
        table.close();
    }

    private static void removeUserFollower(String user, String follower) throws IOException {
        Table table = connection.getTable(TableName.valueOf("userfollower"));
        Delete delete = new Delete(Bytes.toBytes(user));
        delete.addColumn(Bytes.toBytes("cf"), Bytes.toBytes("follower"), Bytes.toBytes(follower));
        table.delete(delete);
        table.close();
    }

    private static String getFollowers(String user) throws IOException {
        Table table = connection.getTable(TableName.valueOf("userfollower"));
        Get get = new Get(Bytes.toBytes(user));
        Result result = table.get(get);
        byte[] value = result.getValue(Bytes.toBytes("cf"), Bytes.toBytes("follower"));
        table.close();
        return Bytes.toString(value);
    }

    private static String getFollowed(String user) throws IOException {
        Table table = connection.getTable(TableName.valueOf("userfollower"));
        Scan scan = new Scan();
        scan.addColumn(Bytes.toBytes("cf"), Bytes.toBytes("follower"));
        ResultScanner resultScanner = table.getScanner(scan);
        StringBuilder sb = new StringBuilder();
        for (Result result : resultScanner) {
            byte[] row = result.getRow();
            byte[] value = result.getValue(Bytes.toBytes("cf"), Bytes.toBytes("follower"));
            String follower = Bytes.toString(value);
            if (follower.equals(user)) {
                sb.append(Bytes.toString(row)).append(" ");
            }
        }
        resultScanner.close();
        table.close();
        return sb.toString();
    }

    private static void scanTable(String tableName) throws IOException {
        Table table = connection.getTable(TableName.valueOf(tableName));
        Scan scan = new Scan();
        ResultScanner resultScanner = table.getScanner(scan);
        for (Result result : resultScanner) {
            byte[] row = result.getRow();
            byte[] value = result.getValue(Bytes.toBytes("cf"), Bytes.toBytes("follower"));
            System.out.println(Bytes.toString(row) + " follows " + Bytes.toString(value));
        }
        resultScanner.close();
        table.close();
    }
}

需要注意的是，程序运行前需要先启动 HBase 的服务。