org.apache.pig.backend.hadoop.executionengine.util

Class MapRedUtil

java.lang.Object

org.apache.pig.backend.hadoop.executionengine.util.MapRedUtil

public class MapRedUtil
extends Object

A class of utility static methods to be used in the hadoop map reduce backend

Field Summary

Fields

Modifier and Type	Field and Description
static String	FILE_SYSTEM_NAME

Constructor Summary

Constructors

Constructor and Description
MapRedUtil()

Method Summary

Methods

Modifier and Type	Method and Description
static FileSpec	checkLeafIsStore(PhysicalPlan plan, PigContext pigContext)
static void	copyTmpFileConfigurationValues(org.apache.hadoop.conf.Configuration fromConf, org.apache.hadoop.conf.Configuration toConf)
static List<org.apache.hadoop.fs.FileStatus>	getAllFileRecursively(List<org.apache.hadoop.fs.FileStatus> files, org.apache.hadoop.conf.Configuration conf) Get all files recursively from the given list of files
static List<List<org.apache.hadoop.mapreduce.InputSplit>>	getCombinePigSplits(List<org.apache.hadoop.mapreduce.InputSplit> oneInputSplits, long maxCombinedSplitSize, org.apache.hadoop.conf.Configuration conf)
static long	getPathLength(org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.FileStatus status)
static long	getPathLength(org.apache.hadoop.fs.FileSystem fs, org.apache.hadoop.fs.FileStatus status, long max) Returns the total number of bytes for this file, or if a directory all files in the directory.
String	inputSplitToString(org.apache.hadoop.mapreduce.InputSplit[] splits)
static <E> Map<E,Pair<Integer,Integer>>	loadPartitionFileFromLocalCache(String keyDistFile, Integer[] totalReducers, byte keyType, org.apache.hadoop.conf.Configuration mapConf) Loads the key distribution sampler file
static void	setupStreamingDirsConfMulti(PigContext pigContext, org.apache.hadoop.conf.Configuration conf) Sets up output and log dir paths for a multi-store streaming job
static void	setupStreamingDirsConfSingle(POStore st, PigContext pigContext, org.apache.hadoop.conf.Configuration conf) Sets up output and log dir paths for a single-store streaming job
static void	setupUDFContext(org.apache.hadoop.conf.Configuration job)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

FILE_SYSTEM_NAME

public static final String FILE_SYSTEM_NAME

See Also:

Constant Field Values

Constructor Detail

MapRedUtil

public MapRedUtil()

Method Detail

loadPartitionFileFromLocalCache

public static <E> Map<E,Pair<Integer,Integer>> loadPartitionFileFromLocalCache(String keyDistFile,
                                                               Integer[] totalReducers,
                                                               byte keyType,
                                                               org.apache.hadoop.conf.Configuration mapConf)
                                                                    throws IOException

Loads the key distribution sampler file

Parameters:

keyDistFile - the name for the distribution file

totalReducers - gets set to the total number of reducers as found in the dist file

keyType - Type of the key to be stored in the return map. It currently treats Tuple as a special case.

Throws:

IOException

copyTmpFileConfigurationValues

public static void copyTmpFileConfigurationValues(org.apache.hadoop.conf.Configuration fromConf,
                                  org.apache.hadoop.conf.Configuration toConf)

setupUDFContext

public static void setupUDFContext(org.apache.hadoop.conf.Configuration job)
                            throws IOException

Throws:

IOException

setupStreamingDirsConfSingle

public static void setupStreamingDirsConfSingle(POStore st,
                                PigContext pigContext,
                                org.apache.hadoop.conf.Configuration conf)
                                         throws IOException

Sets up output and log dir paths for a single-store streaming job

Parameters:

st - - POStore of the current job

pigContext -

conf -

Throws:

IOException

setupStreamingDirsConfMulti

public static void setupStreamingDirsConfMulti(PigContext pigContext,
                               org.apache.hadoop.conf.Configuration conf)
                                        throws IOException

Sets up output and log dir paths for a multi-store streaming job

Parameters:

pigContext -

conf -

Throws:

IOException

checkLeafIsStore

public static FileSpec checkLeafIsStore(PhysicalPlan plan,
                        PigContext pigContext)
                                 throws ExecException

Throws:

ExecException

getAllFileRecursively

public static List<org.apache.hadoop.fs.FileStatus> getAllFileRecursively(List<org.apache.hadoop.fs.FileStatus> files,
                                                          org.apache.hadoop.conf.Configuration conf)
                                                                   throws IOException

Get all files recursively from the given list of files

Parameters:

files - a list of FileStatus

conf - the configuration object

Returns:

the list of fileStatus that contains all the files in the given list and, recursively, all the files inside the directories in the given list

Throws:

IOException

getPathLength

public static long getPathLength(org.apache.hadoop.fs.FileSystem fs,
                 org.apache.hadoop.fs.FileStatus status)
                          throws IOException

Throws:

IOException

getPathLength

public static long getPathLength(org.apache.hadoop.fs.FileSystem fs,
                 org.apache.hadoop.fs.FileStatus status,
                 long max)
                          throws IOException

Returns the total number of bytes for this file, or if a directory all files in the directory.

Parameters:

fs - FileSystem

status - FileStatus

max - Maximum value of total length that will trigger exit. Many times we're only interested whether the total length of files is greater than X or not. In such case, we can exit the function early as soon as the max is reached.

Returns:

Throws:

IOException

getCombinePigSplits

public static List<List<org.apache.hadoop.mapreduce.InputSplit>> getCombinePigSplits(List<org.apache.hadoop.mapreduce.InputSplit> oneInputSplits,
                                                                     long maxCombinedSplitSize,
                                                                     org.apache.hadoop.conf.Configuration conf)
                                                                              throws IOException,
                                                                                     InterruptedException

Throws:

IOException

InterruptedException

inputSplitToString

public String inputSplitToString(org.apache.hadoop.mapreduce.InputSplit[] splits)
                          throws IOException,
                                 InterruptedException

Throws:

IOException

InterruptedException