Hi, I have created the code as below to write a record into hbase table of 1.1.2 version. I have included all the jars present in 1.1.2 hbase lib folder but while executing that I am getting the Error Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/hadoop/hbase/HBaseConfiguration Code package com.hp; import java.io.IOExceptionimport org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Get;
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.client.Table;
import org.apache.hadoop.hbase.util.Bytes;
public class HbasePut
{
public static void main(String[] args) throws IOException
{// You need a configuration object to tell the client where to connect.
// When you create a HBaseConfiguration, it reads in whatever you've set
// into your hbase-site.xml and in hbase-default.xml, as long as these can
// be found on the CLASSPATH
Configuration config = HBaseConfiguration.create();
// Next you need a Connection to the cluster. Create one. When done with it,
// close it (Should start a try/finally after this creation so it gets closed
// for sure but leaving this out for readibility's sake).
Connection connection = ConnectionFactory.createConnection(config); try
{
// This instantiates a Table object that connects you to
// the "myLittleHBaseTable" table (TableName.valueOf turns String into TableName instance).
// When done with it, close it (Should start a try/finally after this creation so it gets
// closed for sure but leaving this out for readibility's sake).
Table table = connection.getTable(TableName.valueOf("myLittleHBaseTable"));
try
{
// To add to a row, use Put. A Put constructor takes the name of the row
// you want to insert into as a byte array. In HBase, the Bytes class has
// utility for converting all kinds of java types to byte arrays.
//In the below, we are converting the String "myLittleRow" into a byte array to
// use as a row key for our update. Once you have a Put instance, you can
// adorn it by setting the names of columns you want to update on the row,
// the timestamp to use in your update, etc.If no timestamp, the server
// applies current time to the edits.
Put p = new Put(Bytes.toBytes("myLittleRow"));
// To set the value you'd like to update in the row 'myLittleRow', specify
// the column family, column qualifier, and value of the table cell you'd
// like to update. The column family must already exist in your table
// schema. The qualifier can be anything. All must be specified as byte
// arrays as hbase is all about byte arrays. Lets pretend the table
// 'myLittleHBaseTable' was created with a family 'myLittleFamily'.
p.add(Bytes.toBytes("myLittleFamily"), Bytes.toBytes("cf1"),Bytes.toBytes("SomeValue"));
// Once you've adorned your Put instance with all the updates you want to
// make, to commit it do the following (The HTable#put method takes the
// Put instance you've been building and pushes the changes you made into // hbase)
table.put(p);
// Now, to retrieve the data we just wrote. The values that come back are
// Result instances. Generally, a Result is an object that will package up
// the hbase return into the form you find most palatable.
/*Get g = new Get(Bytes.toBytes("myLittleRow"));
Result r = table.get(g);
byte [] value = r.getValue(Bytes.toBytes("myLittleFamily"), Bytes.toBytes("cf1"));
// If we convert the value bytes, we should get back 'Some Value', the
// value we inserted at this location.
String valueStr = Bytes.toString(value);
System.out.println("GET: " + valueStr);
// Sometimes, you won't know the row you're looking for. In this case, you
// use a Scanner. This will give you cursor-like interface to the contents
// of the table. To set up a Scanner, do like you did above making a Put
// and a Get, create a Scan. Adorn it with column names, etc.
Scan s = new Scan();
s.addColumn(Bytes.toBytes("myLittleFamily"), Bytes.toBytes("cf1"));
ResultScanner scanner = table.getScanner(s);
try
{
// Scanners return Result instances.
// Now, for the actual iteration. One way is to use a while loop like so:
for (Result rr = scanner.next(); rr != null; rr = scanner.next())
{ // print out the row we found and the columns we were looking for
System.out.println("Found row: " + rr);
}
// The other approach is to use a foreach loop. Scanners are iterable! //
for (Result rr : scanner)
{ //
System.out.println("Found row: " + rr); //
}
}
finally
{
// Make sure you close your scanners when you are done!
// Thats why we have it inside a try/finally clause
scanner.close();
}
*/
// Close your table and cluster connection.
}
finally
{
if (table != null)
table.close();
}
}
finally
{
connection.close();
} }
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