/* * 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. */ import java.util.concurrent.TimeUnit; import com.google.common.util.concurrent.Uninterruptibles; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import org.apache.cassandra.cql3.QueryProcessor; import org.apache.cassandra.cql3.UntypedResultSet; import org.apache.cassandra.db.ConsistencyLevel; import org.apache.cassandra.exceptions.RequestExecutionException; import org.apache.cassandra.exceptions.RequestValidationException; import org.apache.cassandra.service.*; public class ClientOnlyExample { private static final Logger logger = LoggerFactory.getLogger(ClientOnlyExample.class); private static final String KEYSPACE = "keyspace1"; private static final String COLUMN_FAMILY = "standard1"; private static void startClient() throws Exception { StorageService.instance.initClient(); } private static void testWriting() throws Exception { // do some writing. for (int i = 0; i < 100; i++) { QueryProcessor.process(String.format("INSERT INTO %s.%s (id, name, value) VALUES ( 'key%d', 'colb', 'value%d')", KEYSPACE, COLUMN_FAMILY, i, i), ConsistencyLevel.QUORUM); System.out.println("wrote key" + i); } System.out.println("Done writing."); } private static void testReading() throws Exception { // do some queries. for (int i = 0; i < 100; i++) { String query = String.format("SELECT id, name, value FROM %s.%s WHERE id = 'key%d'", KEYSPACE, COLUMN_FAMILY, i); UntypedResultSet.Row row = QueryProcessor.process(query, ConsistencyLevel.QUORUM).one(); System.out.println(String.format("ID: %s, Name: %s, Value: %s", row.getString("id"), row.getString("name"), row.getString("value"))); } } /** * First, bring one or more nodes up. Then run ClientOnlyExample with these VM arguments: * <p/> * -Xmx1G * -Dcassandra.config=/Users/gary/cassandra/conf/cassandra.yaml (optional, will first look for cassandra.yaml on classpath) * <p/> * Pass "write" or "read" into the program to exercise the various methods. * <p/> * Caveats: * <p/> * 1. Much of cassandra is not reentrant. That is, you can't spin a client up, down, then back up in the same jvm. * 2. Because of the above, you still need to force-quit the process. StorageService.stopClient() doesn't (can't) * spin everything down. */ public static void main(String args[]) throws Exception { startClient(); setupKeyspace(); testWriting(); logger.info("Writing is done. Sleeping, then will try to read."); Uninterruptibles.sleepUninterruptibly(1, TimeUnit.SECONDS); testReading(); // no need to do this: // StorageService.instance().decommission(); // do this instead: StorageService.instance.stopClient(); System.exit(0); // the only way to really stop the process. } private static void setupKeyspace() throws RequestExecutionException, RequestValidationException, InterruptedException { QueryProcessor.process("CREATE KEYSPACE IF NOT EXISTS " + KEYSPACE + " WITH replication = {'class': 'SimpleStrategy', 'replication_factor': '1'}", ConsistencyLevel.ANY); QueryProcessor.process("CREATE TABLE IF NOT EXISTS " + KEYSPACE + "." + COLUMN_FAMILY + " (id ascii PRIMARY KEY, name ascii, value ascii )", ConsistencyLevel.ANY); TimeUnit.MILLISECONDS.sleep(1000); } }