There are two ways to read HBase. One is to inherit RichSourceFunction, rewrite the parent method, and the other is to implement the OutputFormat interface. The code is as follows:

Way 1: Inherit RichSourceFunction

package com.my.flink.utils.streaming.hbase;

import com.my.flink.utils.config.ConfigKeys;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.configuration.Configuration;
import org.apache.flink.streaming.api.functions.source.RichSourceFunction;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.util.Iterator;

/**
 * @Description hbase reader
 * @Author jiangxiaozhi
 * @Date 2018/10/17 10:05
 **/
public class HBaseReader extends RichSourceFunction<Tuple2<String, String>> {
    private static final Logger logger = LoggerFactory.getLogger(HBaseReader.class);

    private Connection conn = null;
    private Table table = null;
    private Scan scan = null;

    @Override
    public void open(Configuration parameters) throws Exception {
        super.open(parameters);
        conn = HBaseConnection.getHBaseConn();
        table = conn.getTable(TableName.valueOf(ConfigKeys.HBASE_SOURCE_TABLE()));
        scan = new Scan();
        scan.setStartRow(Bytes.toBytes("1001"));
        scan.setStopRow(Bytes.toBytes("1004"));
        scan.addFamily(Bytes.toBytes(ConfigKeys.HBASE_SOURCE_CF()));

    }

    @Override
    public void run(SourceContext<Tuple2<String, String>> ctx) throws Exception {
        ResultScanner rs = table.getScanner(scan);
        Iterator<Result> iterator = rs.iterator();
        while (iterator.hasNext()) {
            Result result = iterator.next();
            String rowkey = Bytes.toString(result.getRow());
            StringBuffer sb = new StringBuffer();
            for (Cell cell : result.listCells()) {
                String value = Bytes.toString(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());
                sb.append(value).append(",");
            }
            String valueString = sb.replace(sb.length() - 1, sb.length(), "").toString();
            Tuple2<String, String> tuple2 = new Tuple2<>();
            tuple2.setFields(rowkey, valueString);
            ctx.collect(tuple2);
        }

    }

    @Override
    public void cancel() {
        try {
            if (table != null) {
                table.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (IOException e) {
            logger.error("Close HBase Exception:", e.toString());
        }

    }
}

Code and Flink Read and Write Series - Read mysql and write mysql Similarly, specific instructions can be viewed.

Mode 2: Rewrite the TableInputFormat method

    env.createInput(new TableInputFormat[org.apache.flink.api.java.tuple.Tuple2[String, String]] {
      override def mapResultToTuple(r: Result): org.apache.flink.api.java.tuple.Tuple2[String, String] = {
        val rowkey = Bytes.toString(r.getRow)
        val sb = new StringBuffer()
        for (cell: Cell <- r.rawCells()) {
          val value = Bytes.toString(cell.getValueArray, cell.getValueOffset, cell.getValueLength)
          sb.append(value).append(",")
        }
        val valueString = sb.replace(sb.length() - 1, sb.length(), "").toString
        val tuple2 = new org.apache.flink.api.java.tuple.Tuple2[String, String]
        tuple2.setField(rowkey, 0)
        tuple2.setField(valueString, 1)
        tuple2
      }

      override def getTableName: String = HBASE_SOURCE_TABLE

      override def getScanner: Scan = {
        scan
      }

      override def configure(parameters: Configuration): Unit = {
        val conf = HBaseConfiguration.create();
        conf.set(HConstants.ZOOKEEPER_QUORUM, ZOOKEEPER_QUORUM)
        conf.set(HConstants.ZOOKEEPER_CLIENT_PORT, ZOOKEEPER_CLIENT_PORT)
        conn = ConnectionFactory.createConnection(conf)
        table = classOf[HTable].cast(conn.getTable(TableName.valueOf(HBASE_SOURCE_TABLE)))
        scan = new Scan() {
          setStartRow(Bytes.toBytes("1001"))
          setStopRow(Bytes.toBytes("1004"))
          addFamily(Bytes.toBytes(HBASE_SOURCE_CF))
        }
      }

      override def close() = {
        if (table != null) {
          table.close()
        }
        if (conn != null) {
          conn.close()
        }

      }
    })

The env above is Stream Execution Environment.

There are also two ways to write to HBase. Writing is similar to writing to mysql. Here we focus on the implementation of the OutputFormat interface for writing:

package com.my.flink.utils.streaming.hbase;

import com.my.flink.utils.config.ConfigKeys;
import org.apache.flink.api.common.io.OutputFormat;
import org.apache.flink.api.java.tuple.Tuple2;
import org.apache.flink.configuration.Configuration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Table;
import org.apache.hadoop.hbase.util.Bytes;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;

/**
 * @Description HBaseOutputFormat
 * @Author jiangxiaozhi
 * @Date 2018/10/16 14:06
 **/
public class HBaseOutputFormat implements OutputFormat<Tuple2<String, String>> {
    private static final Logger logger = LoggerFactory.getLogger(HBaseOutputFormat.class);

    private org.apache.hadoop.conf.Configuration conf = null;
    private Connection conn = null;
    private Table table = null;

    @Override
    public void configure(Configuration parameters) {
    }

    @Override
    public void open(int taskNumber, int numTasks) throws IOException {
        conn = HBaseConnection.getHBaseConn();
        table = conn.getTable(TableName.valueOf(ConfigKeys.HBASE_SINK_TABLE()));
    }

    @Override
    public void writeRecord(org.apache.flink.api.java.tuple.Tuple2<String, String> record) throws IOException {
        Put put = new Put(Bytes.toBytes(record.f0));
        put.addColumn(Bytes.toBytes(ConfigKeys.HBASE_SINK_CF()), Bytes.toBytes("test1"), Bytes.toBytes(record.f1));
        table.put(put);
    }

    @Override
    public void close() throws IOException {
        if (table != null) {
            table.close();
        }
        if (conn != null) {
            conn.close();
        }
    }
}

In use:

Read HBase:
1. If it's HBaseReader
 Env. addSource (new HBaseReader ()// Generates DataStream
 2. If it is TableInputFormat, see Mode 2 for generating DataStream, env.createInput.....

Store in HBase:
1. If it is HBaseWriter
 Env. addSource (new HBaseWriter ()//HBaseWriter is not implemented, see JdbcWriter
2.dataStream.writeUsingOutputFormat(new HBaseOutputFormat())