HBase(2)JAVA Client

HBase(2)JAVA Client

First of all, how to run jar based on maven plugin.
pom.xml
<build>  

 <plugins>   

  <plugin>   

   <groupId>org.apache.maven.plugins</groupId>

   <artifactId>maven-jar-plugin</artifactId>

   <configuration>

    <archive>

     <manifest>

      <mainClass>com.sillycat.easyhbase.ExecutorApp</mainClass>

     </manifest>

    </archive>

   </configuration>

  </plugin>

 </plugins>  

</build>

And the ExecutorApp is just a simplest Java Application.
package com.sillycat.easyhbase;

 

public class ExecutorApp {      

 public static void main(String[] args) {          

   System.out.println("Nice try.");      

 }

}

Fire and build the jar
>mvn clean install

Run the jar
>java -jar target/easyhbase-1.0.jar 
Nice try.


Error Message
08-05 17:15:46 [WARN] org.apache.hadoop.hbase.util.DynamicClassLoader.<init>(DynamicClassLoader.java:106) - Failed to identify the fs of dir hdfs://ubuntu-master:9000/hbase/lib, ignored java.io.IOException: No FileSystem for scheme: hdfs at org.apache.hadoop.fs.FileSystem.getFileSystemClass(FileSystem.java:2385) at org.apache.hadoop.fs.FileSystem.createFileSystem(FileSystem.java:2392) at org.apache.hadoop.fs.FileSystem.access$200(FileSystem.java:89) at org.apache.hadoop.fs.FileSystem$Cache.getInternal(FileSystem.java:2431) at org.apache.hadoop.fs.FileSystem$Cache.get(FileSystem.java:2413) at org.apache.hadoop.fs.FileSystem.get(FileSystem.java:368) at org.apache.hadoop.fs.Path.getFileSystem(Path.java:296) at org.apache.hadoop.hbase.util.DynamicClassLoader.<init>(DynamicClassLoader.java:104) at org.apache.hadoop.hbase.protobuf.ProtobufUtil.<clinit>(ProtobufUtil.java:202)

Solution:
After add this jar, the problem solved.
<dependency>     

 <groupId>org.apache.hadoop</groupId>

  <artifactId>hadoop-hdfs</artifactId>

  <version>${hadoop.version}</version>

</dependency>

Error Message
An internal error occurred during: "Updating Maven Project".
Unsupported IClasspathEntry kind=4

Solution:
Because I am using eclipse, so I use command mvn eclipse:eclipse to generate the jar dependencies. 
Right click on the project [Properties] —> [Java Build Path] —>[Library] 
Remove all the blue entries starting with “M2_REPO”, then I can use Maven—>Update Project again. Even I can download the source codes.

All the codes are in project easyhbase.

The dependencies are as follow:
<properties>  

 <hadoop.version>2.4.1</hadoop.version>  

 <hbase.version>0.98.4-hadoop2</hbase.version>

</properties> 

 

<dependencies>     

 <dependency>          

  <groupId>commons-logging</groupId>          

  <artifactId>commons-logging</artifactId>          

  <version>1.1.3</version>     

 </dependency>     

 

 <dependency>         

  <groupId>org.apache.hbase</groupId>         

  <artifactId>hbase-hadoop2-compat</artifactId>         

  <version>${hbase.version}</version>     

 </dependency>     

 

 <dependency>         

  <groupId>org.apache.hbase</groupId>

  <artifactId>hbase-common</artifactId>         

  <version>${hbase.version}</version>     

 </dependency>     

 

 <dependency>         

  <groupId>org.apache.hbase</groupId>         

  <artifactId>hbase-client</artifactId>         

  <version>${hbase.version}</version>     

 </dependency>     

 

 <dependency>           

  <groupId>org.apache.hadoop</groupId>           

  <artifactId>hadoop-common</artifactId>           

  <version>${hadoop.version}</version>     

 </dependency>     

 

 <dependency>         

  <groupId>org.apache.hadoop</groupId>         

  <artifactId>hadoop-hdfs</artifactId>         

  <version>${hadoop.version}</version>     

 </dependency>     

 

 <dependency>         

  <groupId>log4j</groupId>         

  <artifactId>log4j</artifactId>         

  <version>1.2.17</version>     

 </dependency>

</dependencies>

The JAVA Client Sample Codes
package com.sillycat.easyhbase;

 

import java.io.IOException;

import java.util.ArrayList;

import java.util.List;

import org.apache.hadoop.conf.Configuration;

import org.apache.hadoop.hbase.Cell;

import org.apache.hadoop.hbase.CellUtil;

import org.apache.hadoop.hbase.HBaseConfiguration;

import org.apache.hadoop.hbase.HColumnDescriptor;

import org.apache.hadoop.hbase.HTableDescriptor;

import org.apache.hadoop.hbase.MasterNotRunningException;

import org.apache.hadoop.hbase.TableName;

import org.apache.hadoop.hbase.ZooKeeperConnectionException;

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.Put;

import org.apache.hadoop.hbase.client.Result;

import org.apache.hadoop.hbase.client.ResultScanner;

import org.apache.hadoop.hbase.client.Scan;

import org.apache.hadoop.hbase.util.Bytes;

 

public class HBaseMain {

  private static Configuration conf = null;

 // setting

 static {

  conf = HBaseConfiguration.create();

 }

 // create table

 

 public static void creatTable(String tableName, String[] familys) throws Exception {

  HBaseAdmin admin = new HBaseAdmin(conf);

  if (admin.tableExists(tableName)) {

   System.out.println("table already exists!");

  } else {

   

  TableName tableNameObject = TableName.valueOf(tableName);

  HTableDescriptor tableDesc = new HTableDescriptor(tableNameObject);

  for (inti = 0; i < familys.length; i++) {

   tableDesc.addFamily(new HColumnDescriptor(familys[i]));

  }

  admin.createTable(tableDesc);

  System.out.println("create table " + tableName + " ok.");

 }

}

 

// delete table

public static void deleteTable(String tableName) throws Exception {

  try {

    HBaseAdmin admin = new HBaseAdmin(conf);

    admin.disableTable(tableName);

    admin.deleteTable(tableName);

    System.out.println("delete table " + tableName + " ok.");

  } catch (MasterNotRunningException e) {

    e.printStackTrace();

  } catch (ZooKeeperConnectionException e) {

    e.printStackTrace();

  }

}

 

// insert one line

public static void addRecord(String tableName, String rowKey, String family, String qualifier, String value) throws Exception {

 try {

  HTable table = new HTable(conf, tableName);

  Put put = new Put(Bytes.toBytes(rowKey));

  put.add(Bytes.toBytes(family), Bytes.toBytes(qualifier), Bytes.toBytes(value));

  table.put(put);

  System.out.println("insert recored " + rowKey + " to table " + tableName + " ok.");

 } catch (IOException e) {

  e.printStackTrace();

}

}

// delete one line

public static void delRecord(String tableName, String rowKey) throws IOException {

  HTable table = new HTable(conf, tableName);

  List list = new ArrayList();

  Delete del = new Delete(rowKey.getBytes());

  list.add(del);

  table.delete(list);

  System.out.println("del recored " + rowKey + " ok.");

}

 

// query for one line

public static void getOneRecord(String tableName, String rowKey) throws IOException {

  HTable table = new HTable(conf, tableName);

  Get get = new Get(rowKey.getBytes());

  Result rs = table.get(get);

  for (Cell cell : rs.rawCells()) {

   System.out.print(new String(CellUtil.cloneRow(cell)) + " ");

   System.out.print(new String(CellUtil.cloneFamily(cell)) + ":");

   System.out.print(new String(CellUtil.cloneQualifier(cell)) + " ");

   System.out.print(cell.getTimestamp() + " ");

   System.out.println(new String(CellUtil.cloneValue(cell))); }

}

 

// list all data

public static void getAllRecord(String tableName) {

  try {

   HTable table = new HTable(conf, tableName);

   Scan s = new Scan();

   ResultScanner ss = table.getScanner(s);

   for (Result r : ss) {

     for (Cell cell : r.rawCells()) {

      System.out.print(new String(CellUtil.cloneRow(cell)) + " ");

      System.out.print(new String(CellUtil.cloneFamily(cell)) + ":");

      System.out.print(new String(CellUtil.cloneQualifier(cell)) + " ");

      System.out.print(cell.getTimestamp() + " ");

      System.out.println(new String(CellUtil.cloneValue(cell)));

     }

   }

  } catch (IOException e) {

   e.printStackTrace();

  }

 }

 

public static void getRangeRecord(String tableName,String startRowKey,String endRowKey){

  try {

    HTable table = new HTable(conf, tableName);

    Scan s = new Scan(startRowKey.getBytes(),endRowKey.getBytes());

    ResultScanner ss = table.getScanner(s);

    for (Result r : ss) {

      for (Cell cell : r.rawCells()) {

       System.out.print(new String(CellUtil.cloneRow(cell)) + " ");

       System.out.print(new String(CellUtil.cloneFamily(cell)) + ":");

       System.out.print(new String(CellUtil.cloneQualifier(cell)) + " ");

       System.out.print(cell.getTimestamp() + " ");

       System.out.println(new String(CellUtil.cloneValue(cell)));

      }

     }

    } catch (IOException e) {

      e.printStackTrace();

    }

   }

 

public static void main(String[] args) {

    try {

      String tablename = "scores"; String[] familys = { "grade", "course" };

      HBaseMain.creatTable(tablename, familys);

 

      // add record sillycat

      HBaseMain.addRecord(tablename, "sillycat-20140723", "grade", "", "5");

      HBaseMain.addRecord(tablename, "sillycat-20140723", "course", "math", "97");      

      HBaseMain.addRecord(tablename, "sillycat-20140723", "course", "art", "87");

      HBaseMain.addRecord(tablename, "sillycat-20130723", "grade", "", "5");

      HBaseMain.addRecord(tablename, "sillycat-20130723", "course", "math", "97");

      HBaseMain.addRecord(tablename, "sillycat-20130723", "course", "art", "87");

      HBaseMain.addRecord(tablename, "sillycat-20120723", "grade", "", "5");

      HBaseMain.addRecord(tablename, "sillycat-20120723", "course", "math", "97");

      HBaseMain.addRecord(tablename, "sillycat-20120723", "course", "art", "87");

 

      // add record kiko

      HBaseMain.addRecord(tablename, "kiko-20140723", "grade", "", "4");

      HBaseMain.addRecord(tablename, "kiko-20140723", "course", "math", "89");

 

      System.out.println("===========get one record========");

      HBaseMain.getOneRecord(tablename, "sillycat");

      System.out.println("===========show all record========");

      HBaseMain.getAllRecord(tablename);

      System.out.println("===========del one record========");

      HBaseMain.delRecord(tablename, "kiko");

      HBaseMain.getAllRecord(tablename);

      System.out.println("===========show all record========");

      HBaseMain.getAllRecord(tablename);

      System.out.print("=============show range record=======");

      HBaseMain.getRangeRecord(tablename, "sillycat-20130101", "sillycat-20141231");

    } catch (Exception e) {

      e.printStackTrace();

    }

   }

  }

References:
http://www.cnblogs.com/panfeng412/archive/2011/08/14/hbase-java-client-programming.html
http://lirenjuan.iteye.com/blog/1470645
http://hbase.apache.org/book/hbase_apis.html

http://blog.linezing.com/?tag=hbase
http://f.dataguru.cn/thread-226503-1-1.html
http://www.cnblogs.com/ggjucheng/p/3379459.html
http://blog.sina.com.cn/s/blog_ae33b83901016azb.html
http://blog.nosqlfan.com/html/3694.html
http://www.infoq.com/cn/news/2011/07/taobao-linhao-hbase
http://blog.csdn.net/xunianchong/article/details/8995019

client performance
http://blog.linezing.com/?p=1378
design row key
http://san-yun.iteye.com/blog/1995829