HBASE08
第 4 章 HBase API
4.1 环境准备
新建项目后在 pom.xml 中添加依赖：
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-server</artifactId>
<version>1.3.1</version>
</dependency>
<dependency>
<groupId>org.apache.hbase</groupId>
<artifactId>hbase-client</artifactId>
<version>1.3.1</version>
</dependency>
4.2 HBaseAPI
4.2.1 获取 Configuration 对象
public static Configuration conf;
static{
//使用 HBaseConfiguration 的单例方法实例化
conf = HBaseConfiguration.create();
conf.set("hbase.zookeeper.quorum", "192.166.9.102");
conf.set("hbase.zookeeper.property.clientPort", "2181");
}
4.2.2 判断表是否存在
public static boolean isTableExist(String tableName) throws
MasterNotRunningException,
ZooKeeperConnectionException, IOException{
//在 HBase 中管理、访问表需要先创建 HBaseAdmin 对象
//Connection connection =
ConnectionFactory.createConnection(conf);
//HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();
HBaseAdmin admin = new HBaseAdmin(conf);
return admin.tableExists(tableName);
}
4.2.3 创建表
public static void createTable(String tableName, String...
columnFamily) throws
MasterNotRunningException, ZooKeeperConnectionException,
IOException{
HBaseAdmin admin = new HBaseAdmin(conf);
//判断表是否存在
if(isTableExist(tableName)){
System.out.println("表" + tableName + "已存在");
//System.exit(0);
}else{
//创建表属性对象,表名需要转字节
HTableDescriptor descriptor = new
HTableDescriptor(TableName.valueOf(tableName));
//创建多个列族
for(String cf : columnFamily){
descriptor.addFamily(new HColumnDescriptor(cf));
}
//根据对表的配置，创建表
admin.createTable(descriptor);
System.out.println("表" + tableName + "创建成功！");
}
}
4.2.4 删除表
public static void dropTable(String tableName) throws
MasterNotRunningException,
ZooKeeperConnectionException, IOException{
HBaseAdmin admin = new HBaseAdmin(conf);
if(isTableExist(tableName)){
admin.disableTable(tableName);
admin.deleteTable(tableName);
System.out.println("表" + tableName + "删除成功！");
}else{
System.out.println("表" + tableName + "不存在！");
}
}
4.2.5 向表中插入数据
public static void addRowData(String tableName, String rowKey,
String columnFamily, String
column, String value) throws IOException{
//创建 HTable 对象
HTable hTable = new HTable(conf, tableName);
//向表中插入数据
Put put = new Put(Bytes.toBytes(rowKey));
//向 Put 对象中组装数据
put.add(Bytes.toBytes(columnFamily), Bytes.toBytes(column),
Bytes.toBytes(value));
hTable.put(put);
hTable.close();
System.out.println("插入数据成功");
}
