Package org.apache.hadoop.examples.pi

Class Util

java.lang.Object

org.apache.hadoop.examples.pi.Util

public class Util
extends java.lang.Object

Utility methods

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Util.Timer	Timer

Field Summary

Fields

Modifier and Type	Field	Description
static java.io.PrintStream	err	Error stream
static java.io.PrintStream	out	Output stream

Constructor Summary

Constructors

Constructor	Description
Util()

Method Summary

Modifier and Type	Method	Description
static int	accuracy(long terms, boolean print)	Estimate accuracy.
static void	checkDirectory(java.io.File dir)	Check local directory.
static <T extends Combinable<T>> java.util.List<T>	combine(java.util.Collection<T> items)	Combine a list of items.
static java.io.PrintWriter	createWriter(java.io.File dir, java.lang.String prefix)	Create a writer of a local file.
static <T,E extends java.util.concurrent.Callable<T>> void	execute(int nThreads, java.util.List<E> callables)	Execute the callables by a number of threads
static java.lang.String	long2string(long n)	Covert a long to a String in comma separated number format.
static java.lang.String	millis2String(long n)	Covert milliseconds to a String.
static long	parseLongVariable(java.lang.String name, java.lang.String s)	Parse a variable.
static java.lang.String	parseStringVariable(java.lang.String name, java.lang.String s)	Parse a variable.
static java.lang.String	pi2string(double pi, long terms)	Convert a pi value to a String.
static void	printBitSkipped(long b)	Print a "bits skipped" message.
static int	printUsage(java.lang.String[] args, java.lang.String usage)	Print usage messages
static long	string2long(java.lang.String s)	Covert a String to a long.

Methods inherited from class java.lang.Object

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

Field Detail

out

public static final java.io.PrintStream out

Output stream

err

public static final java.io.PrintStream err

Error stream

Constructor Detail

Util

public Util()

Method Detail

millis2String

public static java.lang.String millis2String(long n)

Covert milliseconds to a String.

string2long

public static long string2long(java.lang.String s)

Covert a String to a long. This support comma separated number format.

long2string

public static java.lang.String long2string(long n)

Covert a long to a String in comma separated number format.

parseLongVariable

public static long parseLongVariable(java.lang.String name,
                                     java.lang.String s)

Parse a variable.

parseStringVariable

public static java.lang.String parseStringVariable(java.lang.String name,
                                                   java.lang.String s)

Parse a variable.

execute

public static <T,E extends java.util.concurrent.Callable<T>> void execute(int nThreads,
                                                                                java.util.List<E> callables)
                                                                         throws java.lang.InterruptedException,
                                                                                java.util.concurrent.ExecutionException

Execute the callables by a number of threads

Throws:

java.lang.InterruptedException

java.util.concurrent.ExecutionException

printUsage

public static int printUsage(java.lang.String[] args,
                             java.lang.String usage)

Print usage messages

combine

public static <T extends Combinable<T>> java.util.List<T> combine(java.util.Collection<T> items)

Combine a list of items.

checkDirectory

public static void checkDirectory(java.io.File dir)

Check local directory.

createWriter

public static java.io.PrintWriter createWriter(java.io.File dir,
                                               java.lang.String prefix)
                                        throws java.io.IOException

Create a writer of a local file.

Throws:

java.io.IOException

printBitSkipped

public static void printBitSkipped(long b)

Print a "bits skipped" message.

pi2string

public static java.lang.String pi2string(double pi,
                                         long terms)

Convert a pi value to a String.

accuracy

public static int accuracy(long terms,
                           boolean print)

Estimate accuracy.