org.apache.hadoop.io

类 DefaultStringifier<T>

java.lang.Object

org.apache.hadoop.io.DefaultStringifier<T>

类型参数:

T - the class of the objects to stringify

所有已实现的接口:

Closeable, AutoCloseable, Stringifier<T>

public class DefaultStringifier<T>
extends Object
implements Stringifier<T>

DefaultStringifier is the default implementation of the Stringifier interface which stringifies the objects using base64 encoding of the serialized version of the objects. The Serializer and Deserializer are obtained from the SerializationFactory.
DefaultStringifier offers convenience methods to store/load objects to/from the configuration.

构造器概要

构造器

构造器和说明
DefaultStringifier(Configuration conf, Class<T> c)

方法概要

方法

限定符和类型	方法和说明
void	close() Closes this object.
T	fromString(String str) Restores the object from its string representation.
static <K> K	load(Configuration conf, String keyName, Class<K> itemClass) Restores the object from the configuration.
static <K> K[]	loadArray(Configuration conf, String keyName, Class<K> itemClass) Restores the array of objects from the configuration.
static <K> void	store(Configuration conf, K item, String keyName) Stores the item in the configuration with the given keyName.
static <K> void	storeArray(Configuration conf, K[] items, String keyName) Stores the array of items in the configuration with the given keyName.
String	toString(T obj) Converts the object to a string representation

从类继承的方法 java.lang.Object

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

构造器详细资料

DefaultStringifier

public DefaultStringifier(Configuration conf,
                  Class<T> c)

方法详细资料

fromString

public T fromString(String str)
             throws IOException

从接口复制的说明: Stringifier

Restores the object from its string representation.

指定者:

fromString 在接口中 Stringifier<T>

参数:

str - the string representation of the object

返回:

restored object

抛出:

IOException - if the object cannot be restored

toString

public String toString(T obj)
                throws IOException

从接口复制的说明: Stringifier

Converts the object to a string representation

指定者:

toString 在接口中 Stringifier<T>

参数:

obj - the object to convert

返回:

the string representation of the object

抛出:

IOException - if the object cannot be converted

close

public void close()
           throws IOException

从接口复制的说明: Stringifier

Closes this object.

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

指定者:

close 在接口中 Stringifier<T>

抛出:

IOException - if an I/O error occurs

store

public static <K> void store(Configuration conf,
             K item,
             String keyName)
                  throws IOException

Stores the item in the configuration with the given keyName.

类型参数:

K - the class of the item

参数:

conf - the configuration to store

item - the object to be stored

keyName - the name of the key to use

抛出:

IOException - : forwards Exceptions from the underlying Serialization classes.

load

public static <K> K load(Configuration conf,
         String keyName,
         Class<K> itemClass)
              throws IOException

Restores the object from the configuration.

类型参数:

K - the class of the item

参数:

conf - the configuration to use

keyName - the name of the key to use

itemClass - the class of the item

返回:

restored object

抛出:

IOException - : forwards Exceptions from the underlying Serialization classes.

storeArray

public static <K> void storeArray(Configuration conf,
                  K[] items,
                  String keyName)
                       throws IOException

Stores the array of items in the configuration with the given keyName.

类型参数:

K - the class of the item

参数:

conf - the configuration to use

items - the objects to be stored

keyName - the name of the key to use

抛出:

IndexOutOfBoundsException - if the items array is empty

IOException - : forwards Exceptions from the underlying Serialization classes.

loadArray

public static <K> K[] loadArray(Configuration conf,
                String keyName,
                Class<K> itemClass)
                     throws IOException

Restores the array of objects from the configuration.

类型参数:

K - the class of the item

参数:

conf - the configuration to use

keyName - the name of the key to use

itemClass - the class of the item

返回:

restored object

抛出:

IOException - : forwards Exceptions from the underlying Serialization classes.