Java tutorial
/** * 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.cassandra.stress; import java.io.IOException; import java.util.ArrayList; import java.util.List; import com.google.common.util.concurrent.RateLimiter; import org.apache.cassandra.stress.generate.*; import org.apache.cassandra.stress.settings.SettingsLog; import org.apache.cassandra.stress.settings.StressSettings; import org.apache.cassandra.stress.util.JavaDriverClient; import org.apache.cassandra.stress.util.ThriftClient; import org.apache.cassandra.stress.util.Timer; import org.apache.cassandra.thrift.InvalidRequestException; import org.apache.cassandra.transport.SimpleClient; public abstract class Operation { public final StressSettings settings; public final Timer timer; protected final DataSpec spec; private final List<PartitionIterator> partitionCache = new ArrayList<>(); protected List<PartitionIterator> partitions; public static final class DataSpec { public final PartitionGenerator partitionGenerator; final SeedManager seedManager; final Distribution partitionCount; final RatioDistribution useRatio; final Integer targetCount; public DataSpec(PartitionGenerator partitionGenerator, SeedManager seedManager, Distribution partitionCount, Integer targetCount) { this(partitionGenerator, seedManager, partitionCount, null, targetCount); } public DataSpec(PartitionGenerator partitionGenerator, SeedManager seedManager, Distribution partitionCount, RatioDistribution useRatio) { this(partitionGenerator, seedManager, partitionCount, useRatio, null); } private DataSpec(PartitionGenerator partitionGenerator, SeedManager seedManager, Distribution partitionCount, RatioDistribution useRatio, Integer targetCount) { this.partitionGenerator = partitionGenerator; this.seedManager = seedManager; this.partitionCount = partitionCount; this.useRatio = useRatio; this.targetCount = targetCount; } } public Operation(Timer timer, StressSettings settings, DataSpec spec) { this.timer = timer; this.settings = settings; this.spec = spec; } public static interface RunOp { public boolean run() throws Exception; public int partitionCount(); public int rowCount(); } boolean ready(WorkManager permits, RateLimiter rateLimiter) { int partitionCount = (int) spec.partitionCount.next(); if (partitionCount <= 0) return false; partitionCount = permits.takePermits(partitionCount); if (partitionCount <= 0) return false; int i = 0; boolean success = true; for (; i < partitionCount && success; i++) { if (i >= partitionCache.size()) partitionCache.add(PartitionIterator.get(spec.partitionGenerator, spec.seedManager)); success = false; while (!success) { Seed seed = spec.seedManager.next(this); if (seed == null) break; success = reset(seed, partitionCache.get(i)); } } partitionCount = i; if (rateLimiter != null) rateLimiter.acquire(partitionCount); partitions = partitionCache.subList(0, partitionCount); return !partitions.isEmpty(); } protected boolean reset(Seed seed, PartitionIterator iterator) { if (spec.useRatio == null) return iterator.reset(seed, spec.targetCount, isWrite()); else return iterator.reset(seed, spec.useRatio.next(), isWrite()); } public boolean isWrite() { return false; } /** * Run operation * @param client Cassandra Thrift client connection * @throws IOException on any I/O error. */ public abstract void run(ThriftClient client) throws IOException; public void run(SimpleClient client) throws IOException { throw new UnsupportedOperationException(); } public void run(JavaDriverClient client) throws IOException { throw new UnsupportedOperationException(); } public void timeWithRetry(RunOp run) throws IOException { timer.start(); boolean success = false; String exceptionMessage = null; int tries = 0; for (; tries < settings.errors.tries; tries++) { try { success = run.run(); break; } catch (Exception e) { switch (settings.log.level) { case MINIMAL: break; case NORMAL: System.err.println(e); break; case VERBOSE: e.printStackTrace(System.err); break; default: throw new AssertionError(); } exceptionMessage = getExceptionMessage(e); } } timer.stop(run.partitionCount(), run.rowCount(), !success); if (!success) { error(String.format("Operation x%d on key(s) %s: %s%n", tries, key(), (exceptionMessage == null) ? "Data returned was not validated" : "Error executing: " + exceptionMessage)); } } private String key() { List<String> keys = new ArrayList<>(); for (PartitionIterator partition : partitions) keys.add(partition.getKeyAsString()); return keys.toString(); } protected String getExceptionMessage(Exception e) { String className = e.getClass().getSimpleName(); String message = (e instanceof InvalidRequestException) ? ((InvalidRequestException) e).getWhy() : e.getMessage(); return (message == null) ? "(" + className + ")" : String.format("(%s): %s", className, message); } protected void error(String message) throws IOException { if (!settings.errors.ignore) throw new IOException(message); else if (settings.log.level.compareTo(SettingsLog.Level.MINIMAL) > 0) System.err.println(message); } }