com.aliyun.odps.io

Class MapWritable

java.lang.Object

com.aliyun.odps.io.AbstractMapWritable

com.aliyun.odps.io.MapWritable

All Implemented Interfaces:

Configurable, Writable, Map<Writable,Writable>

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

可以用于序列化的Map，使用方法相同，可以在com.aliyun.odps.mapreduce.Mapper 中调用 com.aliyun.odps.mapreduce.MapContext#write(Object, Object)写出。

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K,V>

Constructor Summary

Constructors

Constructor and Description
MapWritable() 默认构造函数。
MapWritable(MapWritable other) 拷贝构造函数

Method Summary

Modifier and Type	Method and Description
void	clear()
boolean	containsKey(Object key)
boolean	containsValue(Object value)
Set<Map.Entry<Writable,Writable>>	entrySet()
boolean	equals(Object obj)
Writable	get(Object key)
int	hashCode()
boolean	isEmpty()
Set<Writable>	keySet()
Writable	put(Writable key, Writable value)
void	putAll(Map<? extends Writable,? extends Writable> t)
void	readFields(DataInput in) 从指定的 DataInput in 反序列化.
Writable	remove(Object key)
int	size()
String	toString()
Collection<Writable>	values()
void	write(DataOutput out) 序列化到指定的 DataOutput out.

Methods inherited from class com.aliyun.odps.io.AbstractMapWritable

getConf, setConf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

Constructor Detail

MapWritable

public MapWritable()

默认构造函数。

MapWritable

public MapWritable(MapWritable other)

拷贝构造函数

Parameters:

另一个待拷贝的 -

Method Detail

clear

public void clear()

Specified by:

clear in interface Map<Writable,Writable>

containsKey

public boolean containsKey(Object key)

Specified by:

containsKey in interface Map<Writable,Writable>

containsValue

public boolean containsValue(Object value)

Specified by:

containsValue in interface Map<Writable,Writable>

entrySet

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

Specified by:

entrySet in interface Map<Writable,Writable>

equals

public boolean equals(Object obj)

Specified by:

equals in interface Map<Writable,Writable>

Overrides:

equals in class Object

get

public Writable get(Object key)

Specified by:

get in interface Map<Writable,Writable>

hashCode

public int hashCode()

Specified by:

hashCode in interface Map<Writable,Writable>

Overrides:

hashCode in class Object

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface Map<Writable,Writable>

keySet

public Set<Writable> keySet()

Specified by:

keySet in interface Map<Writable,Writable>

put

public Writable put(Writable key,
                    Writable value)

Specified by:

put in interface Map<Writable,Writable>

putAll

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

Specified by:

putAll in interface Map<Writable,Writable>

remove

public Writable remove(Object key)

Specified by:

remove in interface Map<Writable,Writable>

size

public int size()

Specified by:

size in interface Map<Writable,Writable>

values

public Collection<Writable> values()

Specified by:

values in interface Map<Writable,Writable>

write

public void write(DataOutput out)
           throws IOException

Description copied from interface: Writable

序列化到指定的 DataOutput out.

Specified by:

write in interface Writable

Overrides:

write in class AbstractMapWritable

Throws:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

Description copied from interface: Writable

从指定的 DataInput in 反序列化.

Specified by:

readFields in interface Writable

Overrides:

readFields in class AbstractMapWritable

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object