com.scaleoutsoftware.soss.client.util

Class HostToPartitionsMapping

java.lang.Object

com.scaleoutsoftware.soss.client.util.HostToPartitionsMapping

All Implemented Interfaces:

java.io.Serializable

public class HostToPartitionsMapping
extends java.lang.Object
implements java.io.Serializable

This class encapsulates mapping of partitions to hosts. It has method for efficient serialization/deserialization. Current partition layout is returned by getCurrent().

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
HostToPartitionsMapping(java.util.Map<java.net.InetAddress,java.util.Set<java.lang.Integer>> mapping)

Method Summary

Modifier and Type	Method and Description
boolean	equals(java.lang.Object o)
int[]	generateEvenItemDistribution(int numItems) Generates the distribution of items to partition in such way that each host has roughly even share of items.
static HostToPartitionsMapping	getCurrent()
static HostToPartitionsMapping	getCurrent(java.lang.Iterable<com.scaleoutsoftware.soss.client.messaging.GatewayDescriptor> gatewayDescriptors) Gets current partition mapping from the list of gateways provided by the server.
java.net.InetAddress	getForPartition(int partition)
java.util.Set<java.net.InetAddress>	getHosts()
java.util.Set<java.lang.Integer>	getLocalPartitions()
int	getNumberOfHosts()
java.util.Set<java.lang.Integer>	getPartitions(java.net.InetAddress host)
int	hashCode()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

HostToPartitionsMapping

public HostToPartitionsMapping(java.util.Map<java.net.InetAddress,java.util.Set<java.lang.Integer>> mapping)

Method Detail

getLocalPartitions

public java.util.Set<java.lang.Integer> getLocalPartitions()

getForPartition

public java.net.InetAddress getForPartition(int partition)

getNumberOfHosts

public int getNumberOfHosts()

getHosts

public java.util.Set<java.net.InetAddress> getHosts()

getPartitions

public java.util.Set<java.lang.Integer> getPartitions(java.net.InetAddress host)

generateEvenItemDistribution

public int[] generateEvenItemDistribution(int numItems)

Generates the distribution of items to partition in such way that each host has roughly even share of items. This is done by round-robin handling of partitions to hosts.

Parameters:

numItems - number of items to distribute

Returns:

array a[N]-partition number for Nth item.

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getCurrent

public static HostToPartitionsMapping getCurrent()
                                          throws com.scaleoutsoftware.soss.client.da.StateServerException

Throws:

com.scaleoutsoftware.soss.client.da.StateServerException

getCurrent

public static HostToPartitionsMapping getCurrent(java.lang.Iterable<com.scaleoutsoftware.soss.client.messaging.GatewayDescriptor> gatewayDescriptors)
                                          throws com.scaleoutsoftware.soss.client.da.StateServerException

Gets current partition mapping from the list of gateways provided by the server.

Parameters:

gatewayDescriptors - list of provided gateway descriptors

Returns:

host to partition mapping

Throws:

com.scaleoutsoftware.soss.client.da.StateServerException - if an error occurs connecting to ScaleOut StateServer.