/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.accumulo.examples.simple.client;
import java.util.Arrays;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map.Entry;
import java.util.concurrent.TimeUnit;
import java.util.Random;
import org.apache.accumulo.core.cli.BatchScannerOpts;
import org.apache.accumulo.core.cli.ClientOnRequiredTable;
import org.apache.accumulo.core.client.AccumuloException;
import org.apache.accumulo.core.client.AccumuloSecurityException;
import org.apache.accumulo.core.client.BatchScanner;
import org.apache.accumulo.core.client.Connector;
import org.apache.accumulo.core.client.TableNotFoundException;
import org.apache.accumulo.core.data.Key;
import org.apache.accumulo.core.data.Range;
import org.apache.accumulo.core.data.Value;
import org.apache.hadoop.io.Text;
import org.apache.log4j.Logger;
import static org.apache.accumulo.examples.simple.client.RandomBatchWriter.abs;
import com.beust.jcommander.Parameter;
/**
* Internal class used to verify validity of data read.
*/
class CountingVerifyingReceiver {
private static final Logger log = Logger.getLogger(CountingVerifyingReceiver.class);
long count = 0;
int expectedValueSize = 0;
HashMap<Text,Boolean> expectedRows;
CountingVerifyingReceiver(HashMap<Text,Boolean> expectedRows, int expectedValueSize) {
this.expectedRows = expectedRows;
this.expectedValueSize = expectedValueSize;
}
public void receive(Key key, Value value) {
String row = key.getRow().toString();
long rowid = Integer.parseInt(row.split("_")[1]);
byte expectedValue[] = RandomBatchWriter.createValue(rowid, expectedValueSize);
if (!Arrays.equals(expectedValue, value.get())) {
log.error("Got unexpected value for " + key + " expected : " + new String(expectedValue) + " got : " + new String(value.get()));
}
if (!expectedRows.containsKey(key.getRow())) {
log.error("Got unexpected key " + key);
} else {
expectedRows.put(key.getRow(), true);
}
count++;
}
}
/**
* Simple example for reading random batches of data from Accumulo. See docs/examples/README.batch for instructions.
*/
public class RandomBatchScanner {
private static final Logger log = Logger.getLogger(CountingVerifyingReceiver.class);
/**
* Generate a number of ranges, each covering a single random row.
*
* @param num
* the number of ranges to generate
* @param min
* the minimum row that will be generated
* @param max
* the maximum row that will be generated
* @param r
* a random number generator
* @param ranges
* a set in which to store the generated ranges
* @param expectedRows
* a map in which to store the rows covered by the ranges (initially mapped to false)
*/
static void generateRandomQueries(int num, long min, long max, Random r, HashSet<Range> ranges, HashMap<Text,Boolean> expectedRows) {
log.info(String.format("Generating %,d random queries...", num));
while (ranges.size() < num) {
long rowid = (abs(r.nextLong()) % (max - min)) + min;
Text row1 = new Text(String.format("row_%010d", rowid));
Range range = new Range(new Text(row1));
ranges.add(range);
expectedRows.put(row1, false);
}
log.info("finished");
}
/**
* Prints a count of the number of rows mapped to false.
*
* @return boolean indicating "were all the rows found?"
*/
private static boolean checkAllRowsFound(HashMap<Text,Boolean> expectedRows) {
int count = 0;
boolean allFound = true;
for (Entry<Text,Boolean> entry : expectedRows.entrySet())
if (!entry.getValue())
count++;
if (count > 0) {
log.warn("Did not find " + count + " rows");
allFound = false;
}
return allFound;
}
/**
* Generates a number of random queries, verifies that the key/value pairs returned were in the queried ranges and that the values were generated by
* {@link RandomBatchWriter#createValue(long, int)}. Prints information about the results.
*
* @param num
* the number of queries to generate
* @param min
* the min row to query
* @param max
* the max row to query
* @param evs
* the expected size of the values
* @param r
* a random number generator
* @param tsbr
* a batch scanner
* @return boolean indicating "did the queries go fine?"
*/
static boolean doRandomQueries(int num, long min, long max, int evs, Random r, BatchScanner tsbr) {
HashSet<Range> ranges = new HashSet<Range>(num);
HashMap<Text,Boolean> expectedRows = new java.util.HashMap<Text,Boolean>();
generateRandomQueries(num, min, max, r, ranges, expectedRows);
tsbr.setRanges(ranges);
CountingVerifyingReceiver receiver = new CountingVerifyingReceiver(expectedRows, evs);
long t1 = System.currentTimeMillis();
for (Entry<Key,Value> entry : tsbr) {
receiver.receive(entry.getKey(), entry.getValue());
}
long t2 = System.currentTimeMillis();
log.info(String.format("%6.2f lookups/sec %6.2f secs%n", num / ((t2 - t1) / 1000.0), ((t2 - t1) / 1000.0)));
log.info(String.format("num results : %,d%n", receiver.count));
return checkAllRowsFound(expectedRows);
}
public static class Opts extends ClientOnRequiredTable {
@Parameter(names="--min", description="miniumum row that will be generated")
long min = 0;
@Parameter(names="--max", description="maximum ow that will be generated")
long max = 0;
@Parameter(names="--num", required=true, description="number of ranges to generate")
int num = 0;
@Parameter(names="--size", required=true, description="size of the value to write")
int size = 0;
@Parameter(names="--seed", description="seed for pseudo-random number generator")
Long seed = null;
}
/**
* Scans over a specified number of entries to Accumulo using a {@link BatchScanner}. Completes scans twice to compare times for a fresh query with those for
* a repeated query which has cached metadata and connections already established.
*/
public static void main(String[] args) throws AccumuloException, AccumuloSecurityException, TableNotFoundException {
Opts opts = new Opts();
BatchScannerOpts bsOpts = new BatchScannerOpts();
opts.parseArgs(RandomBatchScanner.class.getName(), args, bsOpts);
Connector connector = opts.getConnector();
BatchScanner batchReader = connector.createBatchScanner(opts.tableName, opts.auths, bsOpts.scanThreads);
batchReader.setTimeout(bsOpts.scanTimeout, TimeUnit.MILLISECONDS);
Random r;
if (opts.seed == null)
r = new Random();
else
r = new Random(opts.seed);
// do one cold
boolean status = doRandomQueries(opts.num, opts.min, opts.max, opts.size, r, batchReader);
System.gc();
System.gc();
System.gc();
if (opts.seed == null)
r = new Random();
else
r = new Random(opts.seed);
// do one hot (connections already established, metadata table cached)
status = status && doRandomQueries(opts.num, opts.min, opts.max, opts.size, r, batchReader);
batchReader.close();
if (!status) {
System.exit(1);
}
}
}