Package org.apache.tinkerpop.gremlin.process.computer.util

Class EmptyMemory

java.lang.Object

org.apache.tinkerpop.gremlin.process.computer.util.EmptyMemory

All Implemented Interfaces:

Memory, Memory.Admin

public final class EmptyMemory
extends Object
implements Memory.Admin

Author:

Marko A. Rodriguez (http://markorodriguez.com)

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.tinkerpop.gremlin.process.computer.Memory

Memory.Admin, Memory.Exceptions

Method Summary

Modifier and Type	Method	Description
void	add(String key, Object value)	Set the value of the provided key.
Memory	asImmutable()
boolean	exists(String key)	Whether the key exists in the memory.
<R> R	get(String key)	Get the value associated with the provided key.
int	getIteration()	Get the current iteration number.
long	getRuntime()	Get the amount of milliseconds the GraphComputer has been executing thus far.
static EmptyMemory	instance()
Set<String>	keys()	The set of keys currently associated with this memory.
void	set(String key, Object value)
void	setIteration(int iteration)
void	setRuntime(long runtime)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.tinkerpop.gremlin.process.computer.Memory

asMap, isInitialIteration

Methods inherited from interface org.apache.tinkerpop.gremlin.process.computer.Memory.Admin

incrIteration

Method Detail

instance

public static EmptyMemory instance()

setIteration

public void setIteration(int iteration)

Specified by:

setIteration in interface Memory.Admin

setRuntime

public void setRuntime(long runtime)

Specified by:

setRuntime in interface Memory.Admin

asImmutable

public Memory asImmutable()

Specified by:

asImmutable in interface Memory.Admin

keys

public Set<String> keys()

Description copied from interface: Memory

The set of keys currently associated with this memory.

Specified by:

keys in interface Memory

Returns:

the memory's key set.

get

public <R> R get(String key)
          throws IllegalArgumentException

Description copied from interface: Memory

Get the value associated with the provided key.

Specified by:

get in interface Memory

Type Parameters:

R - the type of the value

Parameters:

key - the key of the value

Returns:

the value

Throws:

IllegalArgumentException - is thrown if the key does not exist

set

public void set(String key,
                Object value)
         throws IllegalArgumentException,
                IllegalStateException

Specified by:

set in interface Memory

Throws:

IllegalArgumentException

IllegalStateException

add

public void add(String key,
                Object value)
         throws IllegalArgumentException,
                IllegalStateException

Description copied from interface: Memory

Set the value of the provided key. This is typically called in setup() and/or terminate() of the VertexProgram. If this is called during execute(), there is no guarantee as to the ultimately stored value as call order is indeterminate. It is up to the implementation to determine the states in which this method can be called.

Specified by:

add in interface Memory

Parameters:

key - they key to set a value for

value - the value to set for the key

Throws:

IllegalArgumentException

IllegalStateException

getIteration

public int getIteration()

Description copied from interface: Memory

Get the current iteration number.

Specified by:

getIteration in interface Memory

Returns:

the current iteration

getRuntime

public long getRuntime()

Description copied from interface: Memory

Get the amount of milliseconds the GraphComputer has been executing thus far.

Specified by:

getRuntime in interface Memory

Returns:

the total time in milliseconds

exists

public boolean exists(String key)

Description copied from interface: Memory

Whether the key exists in the memory.

Specified by:

exists in interface Memory

Parameters:

key - key to search the memory for.

Returns:

whether the key exists