Hbase简单操作

来源：互联网发布：专科解题软件编辑：程序博客网时间：2024/05/22 08:25

Hbase是我接触的新东西。项目组也准备使用它开发一个大的服务平台。我也趁机学习学习，先看看Hbase的简单操作方法吧：

虽然Hbase与传统的关系型数据库有很大的不同，但首先建张表还是必须的：

/**
* 定义几个常量
*/
public static HBaseConfiguration conf = new HBaseConfiguration();
static HTable table = null;
/**
* 创建hbase table
* @param table
* @throws IOException
*/
public static void creatTable(String tablename) throws IOException {
HBaseAdmin admin = new HBaseAdmin(conf);
if (!admin.tableExists(new Text(tablename))) { //判断该表名存不存在
HTableDescriptor tableDesc = new HTableDescriptor(tablename);
tableDesc.addFamily(new HColumnDescriptor("ip:")); // 添加表的列族。
tableDesc.addFamily(new HColumnDescriptor("time:"));
tableDesc.addFamily(new HColumnDescriptor("type:"));
tableDesc.addFamily(new HColumnDescriptor("cookie:"));
//注意这个C列,下面我会简单以此列来说明列存储
tableDesc.addFamily(new HColumnDescriptor("c:"));
admin.createTable(tableDesc); //生成表
System.out.println("table create ok!!!");
} else {
System.out.println("table Already exists");
}
}

表建好了就可以插入数据了：

/**
* 插入数据
* @throws Exception
*/
public static void insertData() throws Exception{
//读取日志文件
BufferedReader reader = new BufferedReader(new FileReader("此处为读入的文件名"));
if(table==null)
table = new HTable(conf, new Text(tablename));
String line;
while((line = reader.readLine()) != null){ //是否读到文件的最后一行
//这里我就不说了,先前有说明
LogAccess log = new LogAccess(line);
//这里我使用time+cookie为row关键字,确保不重复,如果cookie记录有重复,将区别对待,这里暂不多做说明
String row = createRow(log.getTime(),log.getCookie());
long lockid = table.startUpdate(new Text(row));
if(!log.getIp().equals("") && log.getIp()!=null)
table.put(lockid, new Text("ip:"), log.getIp().getBytes());
if(!log.getTime().equals("") && log.getTime()!=null)
table.put(lockid, new Text("time:"), log.getTime().getBytes());
if(!log.getType().equals("") && log.getType()!=null)
table.put(lockid, new Text("type:"), log.getType().getBytes());
if(!log.getCookie().equals("") && log.getCookie()!=null)
table.put(lockid, new Text("cookie:"), log.getCookie().getBytes());
//这里要注意,我是往c列中写入了5个字段,你可以想象,我在c列中存入了一个map
if(!log.getRegmark().equals("") && log.getRegmark()!=null)
table.put(lockid, new Text("c:_regmark"), log.getRegmark().getBytes());
if(!log.getRegmark2().equals("") && log.getRegmark2()!=null)
table.put(lockid, new Text("c:_regmark2"), log.getRegmark2().getBytes());
if(!log.getSendshow().equals("") && log.getSendshow()!=null)
table.put(lockid, new Text("c:_sendshow"), log.getSendshow().getBytes());
if(!log.getCurrenturl().equals("") && log.getCurrenturl()!=null)
table.put(lockid, new Text("c:_currenturl"), log.getCurrenturl().getBytes());
if(!log.getAgent().equals("") && log.getAgent()!=null)
table.put(lockid, new Text("c:_agent"), log.getAgent().getBytes());
//存入数据
table.commit(lockid);
}
}