org.apache.hadoop.io

クラス DefaultStringifier<T>

java.lang.Object

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

型パラメータ:

T - the class of the objects to stringify

すべての実装されたインタフェース:

Closeable, AutoCloseable, Stringifier<T>

@InterfaceAudience.Public
 @InterfaceStability.Stable
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.

コンストラクタのサマリー

コンストラクタ

コンストラクタと説明
DefaultStringifier(Configuration conf, Class<T> c)

メソッドのサマリー

修飾子とタイプ	メソッドと説明
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

クラスから継承されたメソッド java.lang.Object

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

コンストラクタの詳細

DefaultStringifier

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

メソッドの詳細

fromString

public T fromString(String str)
             throws IOException

インタフェースからコピーされた説明: Stringifier

Restores the object from its string representation.

定義:

fromString インタフェース内 Stringifier<T>

パラメータ:

str - the string representation of the object

戻り値:

restored object

例外:

IOException - if the object cannot be restored

toString

public String toString(T obj)
                throws IOException

インタフェースからコピーされた説明: Stringifier

Converts the object to a string representation

定義:

toString インタフェース内 Stringifier<T>

パラメータ:

obj - the object to convert

戻り値:

the string representation of the object

例外:

IOException - if the object cannot be converted

close

public void close()
           throws IOException

インタフェースからコピーされた説明: Stringifier

Closes this object.

定義:

close インタフェース内 Closeable

定義:

close インタフェース内 AutoCloseable

定義:

close インタフェース内 Stringifier<T>

例外:

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.

型パラメータ:

K - the class of the item

パラメータ:

conf - the configuration to store

item - the object to be stored

keyName - the name of the key to use

例外:

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.

型パラメータ:

K - the class of the item

パラメータ:

conf - the configuration to use

keyName - the name of the key to use

itemClass - the class of the item

戻り値:

restored object

例外:

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.

型パラメータ:

K - the class of the item

パラメータ:

conf - the configuration to use

items - the objects to be stored

keyName - the name of the key to use

例外:

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.

型パラメータ:

K - the class of the item

パラメータ:

conf - the configuration to use

keyName - the name of the key to use

itemClass - the class of the item

戻り値:

restored object

例外:

IOException - : forwards Exceptions from the underlying Serialization classes.