org.apache.hadoop.io

类 MapWritable

java.lang.Object

org.apache.hadoop.io.AbstractMapWritable

org.apache.hadoop.io.MapWritable

所有已实现的接口:

Map<Writable,Writable>, Configurable, Writable

public class MapWritable
extends AbstractMapWritable
implements Map<Writable,Writable>

A Writable Map.

嵌套类概要

从接口继承的嵌套类/接口 java.util.Map

Map.Entry<K,V>

构造器概要

构造器

构造器和说明
MapWritable() Default constructor.
MapWritable(MapWritable other) Copy constructor.

方法概要

方法

限定符和类型	方法和说明
void	clear()
boolean	containsKey(Object key)
boolean	containsValue(Object value)
Set<Map.Entry<Writable,Writable>>	entrySet()
Writable	get(Object key)
boolean	isEmpty()
Set<Writable>	keySet()
Writable	put(Writable key, Writable value)
void	putAll(Map<? extends Writable,? extends Writable> t)
void	readFields(DataInput in) Deserialize the fields of this object from in.
Writable	remove(Object key)
int	size()
Collection<Writable>	values()
void	write(DataOutput out) Serialize the fields of this object to out.

从类继承的方法 org.apache.hadoop.io.AbstractMapWritable

addToMap, copy, getClass, getConf, getId, setConf

从类继承的方法 java.lang.Object

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

从接口继承的方法 java.util.Map

equals, hashCode

构造器详细资料

MapWritable

public MapWritable()

Default constructor.

MapWritable

public MapWritable(MapWritable other)

Copy constructor.

参数:

other - the map to copy from

方法详细资料

clear

public void clear()

指定者:

clear 在接口中 Map<Writable,Writable>

containsKey

public boolean containsKey(Object key)

指定者:

containsKey 在接口中 Map<Writable,Writable>

containsValue

public boolean containsValue(Object value)

指定者:

containsValue 在接口中 Map<Writable,Writable>

entrySet

public Set<Map.Entry<Writable,Writable>> entrySet()

指定者:

entrySet 在接口中 Map<Writable,Writable>

get

public Writable get(Object key)

指定者:

get 在接口中 Map<Writable,Writable>

isEmpty

public boolean isEmpty()

指定者:

isEmpty 在接口中 Map<Writable,Writable>

keySet

public Set<Writable> keySet()

指定者:

keySet 在接口中 Map<Writable,Writable>

put

public Writable put(Writable key,
           Writable value)

指定者:

put 在接口中 Map<Writable,Writable>

putAll

public void putAll(Map<? extends Writable,? extends Writable> t)

指定者:

putAll 在接口中 Map<Writable,Writable>

remove

public Writable remove(Object key)

指定者:

remove 在接口中 Map<Writable,Writable>

size

public int size()

指定者:

size 在接口中 Map<Writable,Writable>

values

public Collection<Writable> values()

指定者:

values 在接口中 Map<Writable,Writable>

write

public void write(DataOutput out)
           throws IOException

Serialize the fields of this object to out.

指定者:

write 在接口中 Writable

覆盖:

write 在类中 AbstractMapWritable

参数:

out - DataOuput to serialize this object into.

抛出:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

指定者:

readFields 在接口中 Writable

覆盖:

readFields 在类中 AbstractMapWritable

参数:

in - DataInput to deseriablize this object from.

抛出:

IOException