Package org.apache.hadoop.util

Class Options

java.lang.Object

org.apache.hadoop.util.Options

public class Options
extends java.lang.Object

This class allows generic access to variable length type-safe parameter lists.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Options.BooleanOption
static class	Options.ClassOption
static class	Options.FSDataInputStreamOption
static class	Options.FSDataOutputStreamOption
static class	Options.IntegerOption
static class	Options.LongOption
static class	Options.PathOption
static class	Options.ProgressableOption
static class	Options.StringOption

Constructor Summary

Constructors

Constructor	Description
Options()

Method Summary

Modifier and Type	Method	Description
static <base,T extends base> T	getOption(java.lang.Class<T> cls, base[] opts)	Find the first option of the required class.
static <T> T[]	prependOptions(T[] oldOpts, T... newOpts)	Prepend some new options to the old options

Methods inherited from class java.lang.Object

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

Constructor Detail

Options

public Options()

Method Detail

getOption

public static <base,T extends base> T getOption(java.lang.Class<T> cls,
                                                      base[] opts)
                                               throws java.io.IOException

Find the first option of the required class.

Type Parameters:

T - the static class to find

base - the parent class of the array

Parameters:

cls - the dynamic class to find

opts - the list of options to look through

Returns:

the first option that matches

Throws:

java.io.IOException - raised on errors performing I/O.

prependOptions

public static <T> T[] prependOptions(T[] oldOpts,
                                     T... newOpts)

Prepend some new options to the old options

Type Parameters:

T - the type of options

Parameters:

oldOpts - the old options

newOpts - the new options

Returns:

a new array of options