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eventAcquireResource

Class: matlab.DiscreteEventSystem
Package: matlab

Create a resource acquisition event

Syntax

event = eventAcquireResource(resourceSpec,tag)

Description

event = eventAcquireResource(resourceSpec,tag) creates an event to acquire resources from existing Resource Pool blocks. You can specify names and amount of resources to acquire. For more details, see resourceSpecification.

If all the requested resources are not available during the event execution, the acquisition event remains active. When the requested resources become available, the event is rescheduled for immediate execution.

Input Arguments

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Specify the name and the amount of resources to be acquired by the entities.

Custom tag of this entity resource acquisition event. You can use the tag to identify an event when multiple events act on the same entity. For more information about managing multiple events, see Custom Entity Storage Block with Multiple Timer Events.

Output Arguments

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Event that acquires resources for the entity.

Examples

Acquire Resources upon Entry

On entity entry to a storage element, an entity acquires one resource of type Test1. The tag of this resource acquisition event is TestTag.

function [entity,events] = entry(obj, storage, entity, source)
% On entity entry, acquire a resource from the specified pool.    
resourceSpec = obj.resourceSpecification('Test1', 1);
event = obj.eventAcquireResource(resourceSpec, 'TestTag');
end

Custom Block to Acquire Resources

This example shows how to use resource management methods to create a custom entity storage block in which entities acquire resources from specified Resource Pool blocks.

Suppose that you manage a facility that produces parts from two different materials, material 1 and material 2, to fulfill orders. After a part is produced, it is evaluated for quality assurance.

Two testing methods for quality control are:

  • Test 1 is used for parts that are produced from material 1.

  • Test 2 is used for parts that are produced from material 2

After the production phase, parts are tagged based on their material to apply the correct test.

For more information, see Create a Custom Resource Acquirer Block.

classdef CustomBlockAcquireResources < matlab.DiscreteEventSystem
    % Custom resource acquire block example.
    
    methods(Access = protected)
        
        function num = getNumInputsImpl(obj)
            num = 1;
        end
        

        function num = getNumOutputsImpl(obj)
            num = 1;
        end

      
        function entityTypes = getEntityTypesImpl(obj)
            entityTypes(1) = obj.entityType('Part');
        end
        
        function [input, output] = getEntityPortsImpl(obj)
            input  = {'Part'};
            output = {'Part'};
        end
        
        function [storageSpec, I, O] = getEntityStorageImpl(obj)
            storageSpec(1) = obj.queueFIFO('Part', 1);
            I = 1;
            O = 1;
        end
        
        function resNames = getResourceNamesImpl(obj)
            % Define the names of the resources to be acquired.
            resNames = obj.resourceType('Part', {'Test1', 'Test2'}) ;
        end
       
    end
        
    methods
        
        function [entity,events] = entry(obj, storage, entity, source)
            % On entity entry, acquire a resource from the specified pool. 
            if entity.data.Test == 1
            % If the entity is produced from Material1, request Test1.    
            resReq = obj.resourceSpecification('Test1', 1);
            else
            % If the entity is produced from Material2, request Test2.     
            resReq = obj.resourceSpecification('Test2', 1);
            end
            % Acquire the resource from the corresponding pool.
            events = obj.eventAcquireResource(resReq, 'TestTag');
        end
        
        function [entity,events] = resourceAcquired(obj, storage,...  
                                   entity, resources, tag)
        % After the resource acquisition, forward the entity to the output.                    
            events = obj.eventForward('output', storage, 0.0);
        end
        
    end

end

Introduced in R2019a