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HBASE-18269 Jython docs out of date 

Signed-off-by: Mike Drob <mdrob@apache.org>
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Artem Ervits 2018-06-20 09:42:38 -07:00 committed by Mike Drob
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src/main/asciidoc/_chapters/external_apis.adoc
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@ -851,23 +851,14 @@ println(Bytes.toString(value))
=== Setting the Classpath === Setting the Classpath
To use Jython with HBase, your CLASSPATH must include HBase's classpath as well as To use Jython with HBase, your CLASSPATH must include HBase's classpath as well as
the Jython JARs required by your code. First, use the following command on a server the Jython JARs required by your code.
running the HBase RegionServer process, to get HBase's classpath.
Set the path to directory containing the `jython.jar` and each additional Jython-related JAR needed for
your project. Then export HBASE_CLASSPATH pointing to the $JYTHON_HOME env. variable.
[source, bash] [source, bash]
---- ----
$ ps aux |grep regionserver| awk -F 'java.library.path=' {'print $2'} | awk {'print $1'} $ export HBASE_CLASSPATH=/directory/jython.jar
/usr/lib/hadoop/lib/native:/usr/lib/hbase/lib/native/Linux-amd64-64
----
Set the `$CLASSPATH` environment variable to include the path you found in the previous
step, plus the path to `jython.jar` and each additional Jython-related JAR needed for
your project.
[source, bash]
----
$ export CLASSPATH=$CLASSPATH:/usr/lib/hadoop/lib/native:/usr/lib/hbase/lib/native/Linux-amd64-64:/path/to/jython.jar
---- ----
Start a Jython shell with HBase and Hadoop JARs in the classpath: Start a Jython shell with HBase and Hadoop JARs in the classpath:
@ -877,55 +868,52 @@ $ bin/hbase org.python.util.jython
.Table Creation, Population, Get, and Delete with Jython .Table Creation, Population, Get, and Delete with Jython
==== ====
The following Jython code example creates a table, populates it with data, fetches The following Jython code example checks for table,
the data, and deletes the table. if it exists, deletes it and then creates it. Then it
populates the table with data and fetches the data.
[source,jython] [source,jython]
---- ----
import java.lang import java.lang
from org.apache.hadoop.hbase import HBaseConfiguration, HTableDescriptor, HColumnDescriptor, HConstants, TableName from org.apache.hadoop.hbase import HBaseConfiguration, HTableDescriptor, HColumnDescriptor, TableName
from org.apache.hadoop.hbase.client import HBaseAdmin, HTable, Get from org.apache.hadoop.hbase.client import Admin, Connection, ConnectionFactory, Get, Put, Result, Table
from org.apache.hadoop.hbase.io import Cell, RowResult from org.apache.hadoop.conf import Configuration
# First get a conf object. This will read in the configuration # First get a conf object. This will read in the configuration
# that is out in your hbase-*.xml files such as location of the # that is out in your hbase-*.xml files such as location of the
# hbase master node. # hbase master node.
conf = HBaseConfiguration() conf = HBaseConfiguration.create()
connection = ConnectionFactory.createConnection(conf)
admin = connection.getAdmin()
# Create a table named 'test' that has two column families, # Create a table named 'test' that has a column family
# one named 'content, and the other 'anchor'. The colons # named 'content'.
# are required for column family names. tableName = TableName.valueOf("test")
tablename = TableName.valueOf("test") table = connection.getTable(tableName)
desc = HTableDescriptor(tablename) desc = HTableDescriptor(tableName)
desc.addFamily(HColumnDescriptor("content:")) desc.addFamily(HColumnDescriptor("content"))
desc.addFamily(HColumnDescriptor("anchor:"))
admin = HBaseAdmin(conf)
# Drop and recreate if it exists # Drop and recreate if it exists
if admin.tableExists(tablename): if admin.tableExists(tableName):
admin.disableTable(tablename) admin.disableTable(tableName)
admin.deleteTable(tablename) admin.deleteTable(tableName)
admin.createTable(desc)
tables = admin.listTables() admin.createTable(desc)
table = HTable(conf, tablename)
# Add content to 'column:' on a row named 'row_x' # Add content to 'column:' on a row named 'row_x'
row = 'row_x' row = 'row_x'
update = Get(row) put = Put(row)
update.put('content:', 'some content') put.addColumn("content", "qual", "some content")
table.commit(update) table.put(put)
# Now fetch the content just added, returns a byte[] # Now fetch the content just added, returns a byte[]
data_row = table.get(row, "content:") get = Get(row)
data = java.lang.String(data_row.value, "UTF8")
result = table.get(get)
data = java.lang.String(result.getValue("content", "qual"), "UTF8")
print "The fetched row contains the value '%s'" % data print "The fetched row contains the value '%s'" % data
# Delete the table.
admin.disableTable(desc.getName())
admin.deleteTable(desc.getName())
---- ----
==== ====
@ -935,24 +923,23 @@ This example scans a table and returns the results that match a given family qua
[source, jython] [source, jython]
---- ----
# Print all rows that are members of a particular column family
# by passing a regex for family qualifier
import java.lang import java.lang
from org.apache.hadoop.hbase import TableName, HBaseConfiguration
from org.apache.hadoop.hbase.client import Connection, ConnectionFactory, Result, ResultScanner, Table, Admin
from org.apache.hadoop.conf import Configuration
conf = HBaseConfiguration.create()
connection = ConnectionFactory.createConnection(conf)
admin = connection.getAdmin()
tableName = TableName.valueOf('wiki')
table = connection.getTable(tableName)
from org.apache.hadoop.hbase import HBaseConfiguration cf = "title"
from org.apache.hadoop.hbase.client import HTable attr = "attr"
scanner = table.getScanner(cf)
conf = HBaseConfiguration()
table = HTable(conf, "wiki")
col = "title:.*$"
scanner = table.getScanner([col], "")
while 1: while 1:
result = scanner.next() result = scanner.next()
if not result: if not result:
break break
print java.lang.String(result.row), java.lang.String(result.get('title:').value) print java.lang.String(result.row), java.lang.String(result.getValue(cf, attr))
---- ----
==== ====