objectHasMetaData (metadataKey, metadataValue)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

..	list-table:: 
	:widths: 20 80
	:header-rows: 0
	:class: tight-table

	*	-	Category
		-	metadata functions
	*	-	Signature
		-	objectHasMetaData(String metadataKey, String metadataValue) : boolean
	*	-	Description
		-	checks if an object has a certain metadata key with a certain metadata value
	*	-	Arguments
		-	- metadataKey: key of metadata to check for existence
			- metadataValue: value of metadata to check for existence
	*	-	Returns
		-	- true if the model object in the context has the metadata key with the given metadata value
			- false if the model object in the context does not have the metadata key or has the metadata key with a metadata value different from the given metadata value
	*	-	Exceptions
		- .. error::
			This function raises a *No model object in context* exception when the context does not contain a model object
	*	-	Example
		-	The following example shows parts of a code instruction that generates a Java class for each object that has metadata createSpecialService with value true.
			
			Given the input shown in the input section below CodeComposer will generate this class only for object *ExampleObject3* as shown in the output section below.
			
			**Input**

			.. code-block:: xml
				:caption: src/codeinstruction/examples/example-code-instruction-special-service-object-has-meta-data-with-value.xml
				:name: ObjectHasMetaDataWithValue_CodeInstruction
				:linenos:
				:emphasize-lines: 9
				
				<java_package xmlns="https://metafactory.io/xsd/v1/java-codeinstruction"
				              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
				              xsi:schemaLocation="https://metafactory.io/xsd/v1/java-codeinstruction https://metafactory.io/xsd/v1/java-codeinstruction.xsd"
				              name="${pattern.property.java.package.base}.services.special"
				              path="${pattern.property.java.main.directory}"
				              package="domain_model">
					<class  name="${createSpecialServiceClassName(${object.name})}" 
						foreach="object" 
						condition="${objectHasMetaData(createSpecialService,true)}">
					</class>
				</java_package>
			
			.. code-block:: xml
				:caption: src/model/model.xml
				:name: ObjectHasMetaDataWithValue_Model
				:linenos:
				:emphasize-lines: 6, 11, 16
				
				<?xml version="1.0" encoding="UTF-8"?>
				<model xmlns="https://metafactory.io/xsd/v1/model" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="https://metafactory.io/xsd/v1/model https://metafactory.io/xsd/v1/model.xsd">
					<package name="domain_model">
						<object name="ExampleObject1">
							<metadata>
								<createSpecialService></createSpecialService>
							</metadata>
						</object>
						<object name="ExampleObject2">
							<metadata>
								<createSpecialService>false</createSpecialService>
							</metadata>
						</object>
						<object name="ExampleObject3">
							<metadata>
								<createSpecialService>true</createSpecialService>
							</metadata>
						</object>
					</package>
				</model>
	
			**Output**

			.. code-block:: java
				:caption: src/main/java/io/metafactory/codecomposer_reference/services/special/ExampleObject3SpecialService.java
				:name: ObjectHasMetaDataWithValue_Output1
				:linenos:
				:emphasize-lines: 3 

				package io.metafactory.codecomposer_reference.services.special;
				
				public class ExampleObject3SpecialService {
				
				}