JavaHBaseBulkGetExample.java

package com.cloudera.sa.spark.hbase.example;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.Increment;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.api.java.function.Function;
import org.apache.spark.hbase.HBaseContext;
import org.apache.spark.hbase.JavaHBaseContext;

public class JavaHBaseBulkGetExample {
  public static void main(String args[]) {
    if (args.length == 0) {
      System.out
          .println("JavaHBaseBulkGetExample  {master} {tableName}");
    }

    String master = args[0];
    String tableName = args[1];

    JavaSparkContext jsc = new JavaSparkContext(master,
        "JavaHBaseBulkGetExample");
    jsc.addJar("SparkHBase.jar");

    List<byte[]> list = new ArrayList<byte[]>();
    list.add(Bytes.toBytes("1"));
    list.add(Bytes.toBytes("2"));
    list.add(Bytes.toBytes("3"));
    list.add(Bytes.toBytes("4"));
    list.add(Bytes.toBytes("5"));

    JavaRDD<byte[]> rdd = jsc.parallelize(list);

    Configuration conf = HBaseConfiguration.create();
    conf.addResource(new Path("/etc/hbase/conf/core-site.xml"));
    conf.addResource(new Path("/etc/hbase/conf/hbase-site.xml"));

    JavaHBaseContext hbaseContext = new JavaHBaseContext(jsc, conf);

    hbaseContext.bulkGet(tableName, 2, rdd, new GetFunction(),
        new ResultFunction());
  }

  public static class GetFunction implements Function<byte[], Get> {

    private static final long serialVersionUID = 1L;

    public Get call(byte[] v) throws Exception {
      return new Get(v);
    }
  }

  public static class ResultFunction implements Function<Result, String> {

    private static final long serialVersionUID = 1L;

    public String call(Result result) throws Exception {
      Iterator<KeyValue> it = result.list().iterator();
      StringBuilder b = new StringBuilder();

      b.append(Bytes.toString(result.getRow()) + ":");

      while (it.hasNext()) {
        KeyValue kv = it.next();
        String q = Bytes.toString(kv.getQualifier());
        if (q.equals("counter")) {
          b.append("(" + Bytes.toString(kv.getQualifier()) + ","
              + Bytes.toLong(kv.getValue()) + ")");
        } else {
          b.append("(" + Bytes.toString(kv.getQualifier()) + ","
              + Bytes.toString(kv.getValue()) + ")");
        }
      }
      return b.toString();
    }
  }
}