desmoj.core.advancedModellingFeatures

Class Bin

java.lang.Object

desmoj.core.simulator.NamedObject

desmoj.core.simulator.ModelComponent

desmoj.core.simulator.Reportable

desmoj.core.simulator.QueueBased

desmoj.core.advancedModellingFeatures.Bin

All Implemented Interfaces:

Subject<QueueBased,QueueBased.QueueAction>

Direct Known Subclasses:

BinAnimation

public class Bin
extends QueueBased

Bin is the place where producers can store their products for consumers to come and use them up. Bin is used to implement process synchronization between producers and consumers. Producers are producing products and store them using store() in the bin. Consumers make the Bin deliver() the products to use them up. If no or not enough units of a product are available for the consumers, they have to wait in a queue until new units are delivered by a producer. The first sort criterion of the queue is highest queueing priorities first (i.e. not using scheduling priorities - note that this is a somewhat arbitrary choice, as the Bin combines queueing and scheduling features). The second criterion, if a tie-breaker is needed, is the queueing discipline of the underlying queue, e.g. FIFO. The capacity limit can be determined by the user. Bin is derived from QueueBased, which provides all the statistical functionality for a queue.

Version:

DESMO-J, Ver. 2.5.1c copyright (c) 2015

Author:

Soenke Claassen, based on DESMO-C from Thomas Schniewind, 1998 Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

See Also:

QueueBased

Nested Class Summary

Nested classes/interfaces inherited from class desmoj.core.simulator.QueueBased

QueueBased.QueueAction

Field Summary

Fields inherited from class desmoj.core.simulator.QueueBased

FIFO, LIFO, RANDOM, UNDEFINED

Constructor Summary

Constructors

Constructor and Description
Bin(Model owner, java.lang.String name, int sortOrder, int qCapacity, long initialUnits, boolean showInReport, boolean showInTrace) Constructor for a Bin with a number of initial units of a product in it.
Bin(Model owner, java.lang.String name, long initialUnits, boolean showInReport, boolean showInTrace) Constructor for a Bin with a number of initial units of a product in it.

Method Summary

Modifier and Type	Method and Description
double	avgAvail() Returning the average number of products available in the bin over the time since the last reset of the bin.
Reporter	createDefaultReporter() Returns a Reporter to produce a report about this Bin.
long	getAvail() Returns the number of units available at the moment.
long	getConsumers() Returns the number of consumers having visited the Bin.
long	getInitial() Returns the initial number of products in the bin.
long	getMaximum() Returns the maximum number of products in the bin.
boolean	getPassBy() Returns whether entities can pass by other entities which are enqueued before them in the queue.
long	getProducers() Returns the number of producers having used the Bin.
java.lang.String	getQueueStrategy() Returns the implemented queueing discipline of the underlying queue as a String, so it can be displayed in the report.
long	getRefused() Returns the number of entities refused to be enqueued in the queue, because the capacity limit is reached.
void	reset() To reset the statistics of this bin.
boolean	retrieve(long n) Method for consumers to make the Bin deliver a number of n products.
void	setPassBy(boolean newPassBy) Sets the flag passBy to a new value.
void	store(long n) Method for producers to put a number of n new products in the Bin.

Methods inherited from class desmoj.core.simulator.QueueBased

addObserver, averageLength, averageWaitTime, deleteObserver, getQueueLimit, length, maxLength, maxLengthAt, maxWaitTime, maxWaitTimeAt, minLength, minLengthAt, notifyObservers, setQueueImpWarning, stdDevLength, stdDevWaitTime, zeroWaits

Methods inherited from class desmoj.core.simulator.Reportable

getCorrespondingSchedulable, getDescription, getObservations, getReporter, incrementObservations, incrementObservations, reportIsOn, reportOff, reportOn, resetAt, setCorrespondingSchedulable, setDescription, setReporter

Methods inherited from class desmoj.core.simulator.ModelComponent

current, currentEntity, currentEntityAll, currentEvent, currentModel, currentSimProcess, debugIsOn, debugOff, debugOn, getModel, isExperimentCompatible, isModelCompatible, presentTime, sendDebugNote, sendMessage, sendTraceNote, sendWarning, skipTraceNote, skipTraceNote, traceIsOn, traceOff, traceOn

Methods inherited from class desmoj.core.simulator.NamedObject

getName, getQuotedName, toString

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Bin

public Bin(Model owner,
           java.lang.String name,
           int sortOrder,
           int qCapacity,
           long initialUnits,
           boolean showInReport,
           boolean showInTrace)

Constructor for a Bin with a number of initial units of a product in it. Waiting consumer processes are sorted (and thus activated) according to their queueing priorities (highest first) and (if equal) by a queuing discipline as defined by QueueBased, e.g. QueueBased.FIFO or QueueBased.LIFO. The capacity limit of the underlying queue can be chosen, too.

Parameters:

owner - Model : The model this Bin is associated to.

name - java.lang.String : The Bin's name

sortOrder - int : determines the sort order of the underlying queue implementation. Choose a constant from QueueBased like QueueBased.FIFO or QueueBased.LIFO or ...

qCapacity - int : The capacity of the queue, that is how many processes can be enqueued. Zero (0) means unlimited capacity.

initialUnits - long : The units of a product the Bin starts with. Must be positive.

showInReport - boolean : Flag, if Bin should produce a report or not.

showInTrace - boolean : Flag for trace to produce trace messages.

Bin

public Bin(Model owner,
           java.lang.String name,
           long initialUnits,
           boolean showInReport,
           boolean showInTrace)

Constructor for a Bin with a number of initial units of a product in it. Waiting consumer processes are sorted (and thus activated) according to their queueing priorities (highest first) and (if equal) by FIFO. The capacity limit of the underlying queue is unlimited.

Parameters:

owner - Model : The model this Bin is associated to.

name - java.lang.String : The Bin's name

initialUnits - long : The units of a product the Bin starts with. Must be positive.

showInReport - boolean : Flag, if Bin should produce a report or not.

showInTrace - boolean : Flag for trace to produce trace messages.

Method Detail

avgAvail

public double avgAvail()

Returning the average number of products available in the bin over the time since the last reset of the bin.

Returns:

double : The average number of products available in the bin over the time since the last reset of the bin.

createDefaultReporter

public Reporter createDefaultReporter()

Returns a Reporter to produce a report about this Bin.

Returns:

desmoj.report.Reporter : The Reporter for the queue inside this bin

retrieve

public boolean retrieve(long n)
                 throws SuspendExecution

Method for consumers to make the Bin deliver a number of n products. When there are not enough products available or another consumer is first in the queue to be served (and it is not possible to pass by), the current consumer process will be blocked and inserted in the waiting-queue. The order of process activation depends on the order of the internal queue, which is based on the consumers processes' queueing priorities and (if queueing priorities are equal, requiring a tie-breaker) by FIFO or a different discipline as defined in the constructor.

Parameters:

n - long : The number of products the Bin is delivering to the consumer.

Returns:

boolean : Is true if the specified number of units have been delivered successfully, false otherwise (i.e. capacity limit of the queue is reached).

Throws:

SuspendExecution

getAvail

public long getAvail()

Returns the number of units available at the moment.

Returns:

long : The number of units available at the moment.

getConsumers

public long getConsumers()

Returns the number of consumers having visited the Bin.

Returns:

long : The number of consumers having visited the bin.

getInitial

public long getInitial()

Returns the initial number of products in the bin.

Returns:

long : The number of products the bin started with.

getMaximum

public long getMaximum()

Returns the maximum number of products in the bin.

Returns:

long : The maximum number of products in the bin.

getPassBy

public boolean getPassBy()

Returns whether entities can pass by other entities which are enqueued before them in the queue.

Returns:

boolean : Indicates whether entities can pass by other entities which are enqueued before them in the queue.

getProducers

public long getProducers()

Returns the number of producers having used the Bin.

Returns:

long : The number of producers having put products in the bin.

getQueueStrategy

public java.lang.String getQueueStrategy()

Returns the implemented queueing discipline of the underlying queue as a String, so it can be displayed in the report.

Returns:

String : The String indicating the queueing discipline.

getRefused

public long getRefused()

Returns the number of entities refused to be enqueued in the queue, because the capacity limit is reached.

Returns:

long : The number of entities refused to be enqueued in the queue.

reset

public void reset()

To reset the statistics of this bin. The number of available products at this moment and the processes waiting in the queue are not changed. But all statistic counters are reset. The QueueBased is also reset.

Overrides:

reset in class QueueBased

setPassBy

public void setPassBy(boolean newPassBy)

Sets the flag passBy to a new value. PassBy is indicating whether entities can pass by other entities which are enqueued before them in the queue.

Parameters:

newPassBy - boolean : The new value of passBy. Set it to true if you want entities to pass by other entities which are enqueued before them in the queue. Set it to false if you don't want entities to overtake other entities in the queue.

store

public void store(long n)

Method for producers to put a number of n new products in the Bin. When producers store() new products n is positive. Producers can always store products into the Bin and will never be inserted in a queue and blocked, because the Bin has no capacity limit..

Parameters:

n - long : The number of products put into the Bin.