我正在做一个项目,其中我需要插入数据到Cassandra数据库。因此,我使用Pelops client。
我有一个多线程的代码,将插入到卡桑德拉数据库使用Pelops client。我使用ExecutorService来实现这一点。
在我的程序中,每个线程都会在某个范围内工作,比如
Thread1 will work on 1 to 20
Thread2 will work on 21 to 40
...
...下面是我用来插入Cassandra数据库的代码-
private static int noOfThreads = 5;
private static int noOfTasks = 100;
private static int startRange = 1;
public static void main(String[] args) {
LOG.info("Loading data in Cassandra database..!!");
ExecutorService service = Executors.newFixedThreadPool(noOfThreads);
try {
// queue some tasks
for (int i = 0, nextId = startRange; i < noOfThreads; i++, nextId += noOfTasks) {
service.submit(new CassandraTask(nextId, noOfTasks));
}
service.shutdown();
service.awaitTermination(Long.MAX_VALUE, TimeUnit.DAYS);
} catch (InterruptedException e) {
LOG.warn("Threw a Interrupted Exception in" + CNAME + ".PelopsLnPClient: boss told me to stop...Not my fault!!");
} catch (Exception e) {
LOG.error("Threw a Exception in" + CNAME + e);
}
}下面是实现Runnable interface的CassandraTask class
class CassandraTask implements Runnable {
private final int id;
private final int noOfTasks;
private final String nodes = "localhost";
private final String thrift_connection_pool = "Test Cluster";
private final String keyspace = "my_keyspace";
private final String column_family = "PROFILE_USER";
public CassandraTask(int nextId, int noOfTasks) {
this.id = nextId;
this.noOfTasks = noOfTasks;
}
public void run() {
try {
cassandraConnection();
Mutator mutator = Pelops.createMutator(thrift_connection_pool);
for (int userId = id; userId < id + noOfTasks; userId++) {
mutator.writeColumns(column_family, String.valueOf(userId),
mutator.newColumnList(
mutator.newColumn("unt", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("rtising", "{\"lv\":[{\"v\":{\"thirdPartyAdsOnhostdomain\":null,\"hostdomainAdsOnThirdParty\":null,\"userId\":" + userId + "},\"cn\":2}],\"lmd\":20130206211109}"),
mutator.newColumn("selling_price_main_cats", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("and_keyword_rules", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("categories_purchased", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("omer_service", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("graphic", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}"),
mutator.newColumn("rite_searches", "{\"lv\":[{\"v\":{\"regSiteId\":null,\"userState\":null,\"userId\":" + userId + "},\"cn\":1}],\"lmd\":20130206211109}")
));
}
mutator.execute(ConsistencyLevel.ONE);
} catch (Exception e) {
System.err.println("Threw a Exception in " + e);
} finally {
Pelops.shutdown();
}
}
/**
* Making a Cassandra Connection by adding nodes
*
/
private void cassandraConnection() {
Cluster cluster = new Cluster(nodes, 9160);
Pelops.addPool(thrift_connection_pool, cluster, keyspace);
}
}每当我运行上面的程序时,我总是得到下面的异常-
Threw a Exception in java.lang.RuntimeException: exception while registering MBean, com.scale7.cassandra.pelops.pool:type=PooledNode-my_keyspace-localhost有人能帮我解决这个问题吗?我在这里做错了什么?我相信我在这里犯了一些小错误?如果我运行得很慢,那么我就不会得到这个异常。我所说的慢,是指在代码中设置断点。不知怎么的很奇怪。
我正在使用Cassandra 1.2.3
任何帮助都将不胜感激。
发布于 2013-04-09 22:46:56
您使用的是哪个客户端版本?据我所知,每个线程创建一个池(具有相同的名称!)到cassandra,每一个都关闭Pelops客户端。
在主类中移动池创建,只创建一个池并从线程访问它,并且在最后一个线程执行execute方法之前从不调用Pelops.shutdown()。
卡洛
https://stackoverflow.com/questions/15891431
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