在Eclipse中运行JAVA代码远程操作HBase的示例
下面是一个在Windows的Eclipse中通过JAVA操作一个Linux上运行的hbase的示例。
Hbase的配置需要注意下面一些要点:
1，服务器端用主机名配置hadoop和hbase，不要用IP
比如如下：
<property>
<name>hbase.zookeeper.quorum</name>
<value>hadoopsrv</value>
</property>
2，hbase运行的机器上的机器名不能叫localhost
改/etc/sysconfig/network中的HOSTNAME
比如:
HOSTNAME=hadoopsrv
3，修改eclipse运行的windows客户端的C:\Windows\System32\drivers\etc\hosts文件.
对应到hbase运行服务器的ip,比如:
192.168.2.6 hadoopsrv
JAVA代码如下
- package org.apache.hadoop.hbase;
- import java.io.IOException;
- import java.util.ArrayList;
- import java.util.List;
- import org.apache.hadoop.conf.Configuration;
- import org.apache.hadoop.hbase.client.Delete;
- import org.apache.hadoop.hbase.client.Get;
- import org.apache.hadoop.hbase.client.HBaseAdmin;
- import org.apache.hadoop.hbase.client.HTable;
- import org.apache.hadoop.hbase.client.HTablePool;
- import org.apache.hadoop.hbase.client.Put;
- import org.apache.hadoop.hbase.client.Result;
- import org.apache.hadoop.hbase.client.ResultScanner;
- import org.apache.hadoop.hbase.client.Scan;
- public class HbaseTest {
- private HBaseAdmin admin = null;
- // 定义配置对象HBaseConfiguration
- private HBaseConfiguration cfg = null;
- public HbaseTest() throws Exception {
- Configuration HBASE_CONFIG = new Configuration();
- HBASE_CONFIG.set("hbase.zookeeper.quorum", "192.168.2.6");
- HBASE_CONFIG.set("hbase.zookeeper.property.clientPort", "2181");
- cfg = new HBaseConfiguration(HBASE_CONFIG);
- admin = new HBaseAdmin(cfg);
- }
- // 创建一张表，指定表名，列族
- public void createTable(String tableName, String columnFarily)
- throws Exception {
- if (admin.tableExists(tableName)) {
- System.out.println(tableName + "存在！");
- System.exit(0);
- } else {
- HTableDescriptor tableDesc = new HTableDescriptor(tableName);
- tableDesc.addFamily(new HColumnDescriptor(columnFarily));
- admin.createTable(tableDesc);
- System.out.println("创建表成功！");
- }
- }
- // Hbase获取所有的表信息
- public List getAllTables() {
- List<String> tables = null;
- if (admin != null) {
- try {
- HTableDescriptor[] allTable = admin.listTables();
- if (allTable.length > 0)
- tables = new ArrayList<String>();
- for (HTableDescriptor hTableDescriptor : allTable) {
- tables.add(hTableDescriptor.getNameAsString());
- System.out.println(hTableDescriptor.getNameAsString());
- }
- } catch (IOException e) {
- e.printStackTrace();
- }
- }
- return tables;
- }
- // Hbase中往某个表中添加一条记录
- public boolean addOneRecord(String table, String key, String family,
- String col, byte[] dataIn) {
- HTablePool tp = new HTablePool(cfg, 1000);
- HTable tb = (HTable) tp.getTable(table);
- Put put = new Put(key.getBytes());
- put.add(family.getBytes(), col.getBytes(), dataIn);
- try {
- tb.put(put);
- System.out.println("插入数据条" + key + "成功！！！");
- return true;
- } catch (IOException e) {
- System.out.println("插入数据条" + key + "失败！！！");
- return false;
- }
- }
- // Hbase表中记录信息的查询
- public void getValueFromKey(String table, String key) {
- HTablePool tp = new HTablePool(cfg, 1000);
- HTable tb = (HTable) tp.getTable(table);
- Get get = new Get(key.getBytes());
- try {
- Result rs = tb.get(get);
- if (rs.raw().length == 0) {
- System.out.println("不存在关键字为" + key + "的行！!");
- } else {
- for (KeyValue kv : rs.raw()) {
- System.out.println(new String(kv.getKey()) + " "
- + new String(kv.getValue()));
- }
- }
- } catch (IOException e) {
- e.printStackTrace();
- }
- }
- // 显示所有数据，通过HTable Scan类获取已有表的信息
- public void getAllData(String tableName) throws Exception {
- HTable table = new HTable(cfg, tableName);
- Scan scan = new Scan();
- ResultScanner rs = table.getScanner(scan);
- for (Result r : rs) {
- for (KeyValue kv : r.raw()) {
- System.out.println(new String(kv.getKey())
- + new String(kv.getValue()));
- }
- }
- }
- // Hbase表中记录信息的删除
- public boolean deleteRecord(String table, String key) {
- HTablePool tp = new HTablePool(cfg, 1000);
- HTable tb = (HTable) tp.getTable(table);
- Delete de = new Delete(key.getBytes());
- try {
- tb.delete(de);
- return true;
- } catch (IOException e) {
- System.out.println("删除记录" + key + "异常！！！");
- return false;
- }
- }
- // Hbase中表的删除
- public boolean deleteTable(String table) {
- try {
- if (admin.tableExists(table)) {
- admin.disableTable(table);
- admin.deleteTable(table);
- System.out.println("删除表" + table + "!!!");
- }
- return true;
- } catch (IOException e) {
- System.out.println("删除表" + table + "异常!!!");
- return false;
- }
- }
- // 测试函数
- public static void main(String[] args) {
- try {
- HbaseTest hbase = new HbaseTest();
- // hbase.createTable("student", "fam1");
- // hbase.getAllTables();
- // hbase.addOneRecord("student","id1","fam1","name","Jack".getBytes());
- // hbase.addOneRecord("student","id1","fam1","address","HZ".getBytes());
- // hbase.getValueFromKey("student","id1");
- // hbase.getAllData("student");
- //hbase.deleteRecord("student", "id1");
- hbase.deleteTable("student");
- } catch (Exception e) {
- e.printStackTrace();
- }
- }
- }