Metrics synchronous instruments

.gitignore

@@ -4,3 +4,4 @@ build
 # Autosave files
 *.asv
 *.swp
+.vscode/settings.json

CMakeLists.txt

@@ -98,7 +98,7 @@ set(LIBMEXCLASS_FETCH_CONTENT_NAME libmexclass)
 
 set(LIBMEXCLASS_FETCH_CONTENT_GIT_REPOSITORY "https://github.com/mathworks/libmexclass.git")
 
-set(LIBMEXCLASS_FETCH_CONTENT_GIT_TAG "77f3d72") 
+set(LIBMEXCLASS_FETCH_CONTENT_GIT_TAG "bf16a65") 
 
 set(LIBMEXCLASS_FETCH_CONTENT_SOURCE_SUBDIR "libmexclass/cpp")
 
@@ -187,22 +187,26 @@ if(WITH_OTLP_GRPC)
     endif()
 endif()
 
-set(TRACE_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/trace/include) 
+set(TRACE_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/trace/include)
+set(METRICS_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/metrics/include)
 set(CONTEXT_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/context/include) 
 set(BAGGAGE_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/baggage/include) 
 set(COMMON_API_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/common/include) 
 set(TRACE_SDK_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/trace/include)
+set(METRICS_SDK_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/metrics/include)
 set(COMMON_SDK_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/common/include)
 set(OTLP_EXPORTER_INCLUDE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/include)
-set(OPENTELEMETRY_PROXY_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR} ${TRACE_API_INCLUDE_DIR} ${CONTEXT_API_INCLUDE_DIR} ${BAGGAGE_API_INCLUDE_DIR} ${COMMON_API_INCLUDE_DIR} ${TRACE_SDK_INCLUDE_DIR} ${COMMON_SDK_INCLUDE_DIR} ${OTLP_EXPORTER_INCLUDE_DIR} ${OTEL_CPP_PREFIX}/include)
+set(OPENTELEMETRY_PROXY_INCLUDE_DIRS ${CMAKE_CURRENT_SOURCE_DIR} ${TRACE_API_INCLUDE_DIR} ${METRICS_API_INCLUDE_DIR} ${CONTEXT_API_INCLUDE_DIR} ${BAGGAGE_API_INCLUDE_DIR} ${COMMON_API_INCLUDE_DIR} ${TRACE_SDK_INCLUDE_DIR} ${METRICS_SDK_INCLUDE_DIR} ${COMMON_SDK_INCLUDE_DIR} ${OTLP_EXPORTER_INCLUDE_DIR} ${OTEL_CPP_PREFIX}/include)
 
 set(OPENTELEMETRY_PROXY_FACTORY_CLASS_NAME OtelMatlabProxyFactory)
 set(OPENTELEMETRY_PROXY_FACTORY_SOURCES_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 set(TRACE_API_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/trace/src)
+set(METRICS_API_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/metrics/src)
 set(CONTEXT_API_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/context/src)
 set(BAGGAGE_API_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/baggage/src)
 set(COMMON_API_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/api/common/src)
 set(TRACE_SDK_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/trace/src)
+set(METRICS_SDK_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/metrics/src)
 set(COMMON_SDK_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/sdk/common/src)
 set(OTLP_EXPORTER_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/src)
 set(OPENTELEMETRY_PROXY_SOURCES
@@ -212,6 +216,12 @@ set(OPENTELEMETRY_PROXY_SOURCES
     ${TRACE_API_SOURCE_DIR}/SpanProxy.cpp
     ${TRACE_API_SOURCE_DIR}/SpanContextProxy.cpp
     ${COMMON_API_SOURCE_DIR}/attribute.cpp
+    ${METRICS_API_SOURCE_DIR}/MeterProviderProxy.cpp
+    ${METRICS_API_SOURCE_DIR}/MeterProxy.cpp
+    ${METRICS_API_SOURCE_DIR}/CounterProxy.cpp
+    ${METRICS_API_SOURCE_DIR}/UpDownCounterProxy.cpp
+    ${METRICS_API_SOURCE_DIR}/HistogramProxy.cpp
+    ${METRICS_API_SOURCE_DIR}/SynchronousInstrumentProxyFactory.cpp
     ${CONTEXT_API_SOURCE_DIR}/TextMapPropagatorProxy.cpp
     ${CONTEXT_API_SOURCE_DIR}/CompositePropagatorProxy.cpp
     ${CONTEXT_API_SOURCE_DIR}/TextMapCarrierProxy.cpp
@@ -221,14 +231,21 @@ set(OPENTELEMETRY_PROXY_SOURCES
     ${TRACE_SDK_SOURCE_DIR}/SimpleSpanProcessorProxy.cpp
     ${TRACE_SDK_SOURCE_DIR}/BatchSpanProcessorProxy.cpp
     ${TRACE_SDK_SOURCE_DIR}/ParentBasedSamplerProxy.cpp
+    ${METRICS_SDK_SOURCE_DIR}/MeterProviderProxy.cpp
+    ${METRICS_SDK_SOURCE_DIR}/ViewProxy.cpp
+    ${METRICS_SDK_SOURCE_DIR}/PeriodicExportingMetricReaderProxy.cpp
     ${COMMON_SDK_SOURCE_DIR}/resource.cpp)
 if(WITH_OTLP_HTTP)
-    set(OPENTELEMETRY_PROXY_SOURCES ${OPENTELEMETRY_PROXY_SOURCES} 
-	${OTLP_EXPORTER_SOURCE_DIR}/OtlpHttpSpanExporterProxy.cpp)
+    set(OPENTELEMETRY_PROXY_SOURCES 
+    ${OPENTELEMETRY_PROXY_SOURCES} 
+    ${OTLP_EXPORTER_SOURCE_DIR}/OtlpHttpSpanExporterProxy.cpp
+    ${OTLP_EXPORTER_SOURCE_DIR}/OtlpHttpMetricExporterProxy.cpp)
 endif()
 if(WITH_OTLP_GRPC)
-    set(OPENTELEMETRY_PROXY_SOURCES ${OPENTELEMETRY_PROXY_SOURCES} 
-        ${OTLP_EXPORTER_SOURCE_DIR}/OtlpGrpcSpanExporterProxy.cpp)
+    set(OPENTELEMETRY_PROXY_SOURCES 
+    ${OPENTELEMETRY_PROXY_SOURCES}
+    ${OTLP_EXPORTER_SOURCE_DIR}/OtlpGrpcSpanExporterProxy.cpp
+    ${OTLP_EXPORTER_SOURCE_DIR}/OtlpGrpcMetricExporterProxy.cpp)
 endif()
 
 libmexclass_client_add_proxy_library(
@@ -277,16 +294,19 @@ set(OTEL_CPP_LINK_LIBRARIES ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX
 	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_trace${CMAKE_STATIC_LIBRARY_SUFFIX}
 	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_version${CMAKE_STATIC_LIBRARY_SUFFIX}
 	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_logs${CMAKE_STATIC_LIBRARY_SUFFIX}
+	${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_metrics${CMAKE_STATIC_LIBRARY_SUFFIX}
 	${Protobuf_LIBRARIES})
 if(WITH_OTLP_HTTP)
     set(OTEL_CPP_LINK_LIBRARIES ${OTEL_CPP_LINK_LIBRARIES} ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_http${CMAKE_STATIC_LIBRARY_SUFFIX}
 	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_http_client${CMAKE_STATIC_LIBRARY_SUFFIX}
+	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_http_metric${CMAKE_STATIC_LIBRARY_SUFFIX}
 	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_http_client_curl${CMAKE_STATIC_LIBRARY_SUFFIX}
 	    ${CURL_LIBRARIES})
 endif()
 if(WITH_OTLP_GRPC)
     set(OTEL_CPP_LINK_LIBRARIES ${OTEL_CPP_LINK_LIBRARIES} ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_grpc${CMAKE_STATIC_LIBRARY_SUFFIX}
 	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_grpc_client${CMAKE_STATIC_LIBRARY_SUFFIX}
+	    ${OTEL_CPP_PREFIX}/lib/${CMAKE_STATIC_LIBRARY_PREFIX}opentelemetry_exporter_otlp_grpc_metrics${CMAKE_STATIC_LIBRARY_SUFFIX}
             ${OTEL_CPP_PREFIX}/lib/${CMAKE_SHARED_LIBRARY_PREFIX}opentelemetry_proto_grpc${OTEL_PROTO_LIBRARY_SUFFIX}
 	    gRPC::grpc++
 	    absl::synchronization)
@@ -373,22 +393,37 @@ libmexclass_client_install(
 
 # Install M files
 set(TRACE_API_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/api/trace/+opentelemetry)
+set(METRICS_API_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/api/metrics/+opentelemetry)
 set(CONTEXT_API_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/api/context/+opentelemetry)
 set(BAGGAGE_API_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/api/baggage/+opentelemetry)
 set(COMMON_API_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/api/common/+opentelemetry)
 set(TRACE_SDK_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/sdk/trace/+opentelemetry)
-set(DEFAULT_EXPORTER_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/defaultSpanExporter.m)
-set(OTLP_HTTP_EXPORTER_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpHttpSpanExporter.m)
-set(OTLP_GRPC_EXPORTER_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpGrpcSpanExporter.m)
+set(METRICS_SDK_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/sdk/metrics/+opentelemetry)
+set(COMMON_SDK_MATLAB_SOURCES ${CMAKE_CURRENT_SOURCE_DIR}/sdk/common/+opentelemetry)
+set(EXPORTER_MATLAB_SOURCES 
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/defaultSpanExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/defaultMetricExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpValidator.m)
+set(OTLP_HTTP_EXPORTER_MATLAB_SOURCES 
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpHttpSpanExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpHttpMetricExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpHttpValidator.m)
+set(OTLP_GRPC_EXPORTER_MATLAB_SOURCES 
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpGrpcSpanExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpGrpcMetricExporter.m
+    ${CMAKE_CURRENT_SOURCE_DIR}/exporters/otlp/+opentelemetry/+exporters/+otlp/OtlpGrpcValidator.m)
 
 set(OTLP_EXPORTERS_DIR +opentelemetry/+exporters/+otlp)
 
 install(DIRECTORY ${TRACE_API_MATLAB_SOURCES} DESTINATION .)
+install(DIRECTORY ${METRICS_API_MATLAB_SOURCES} DESTINATION .)
 install(DIRECTORY ${CONTEXT_API_MATLAB_SOURCES} DESTINATION .)
 install(DIRECTORY ${BAGGAGE_API_MATLAB_SOURCES} DESTINATION .)
 install(DIRECTORY ${COMMON_API_MATLAB_SOURCES} DESTINATION .)
 install(DIRECTORY ${TRACE_SDK_MATLAB_SOURCES} DESTINATION .)
-install(FILES ${DEFAULT_EXPORTER_MATLAB_SOURCES} DESTINATION ${OTLP_EXPORTERS_DIR})
+install(DIRECTORY ${METRICS_SDK_MATLAB_SOURCES} DESTINATION .)
+install(DIRECTORY ${COMMON_SDK_MATLAB_SOURCES} DESTINATION .)
+install(FILES ${EXPORTER_MATLAB_SOURCES} DESTINATION ${OTLP_EXPORTERS_DIR})
 if(WITH_OTLP_HTTP)
     install(FILES ${OTLP_HTTP_EXPORTER_MATLAB_SOURCES} DESTINATION ${OTLP_EXPORTERS_DIR})
 endif()

OtelMatlabProxyFactory.cpp

@@ -22,17 +22,23 @@
 #include "opentelemetry-matlab/sdk/trace/AlwaysOffSamplerProxy.h"
 #include "opentelemetry-matlab/sdk/trace/TraceIdRatioBasedSamplerProxy.h"
 #include "opentelemetry-matlab/sdk/trace/ParentBasedSamplerProxy.h"
+#include "opentelemetry-matlab/sdk/metrics/MeterProviderProxy.h"
+#include "opentelemetry-matlab/sdk/metrics/ViewProxy.h"
+#include "opentelemetry-matlab/sdk/metrics/PeriodicExportingMetricReaderProxy.h"
 #ifdef WITH_OTLP_HTTP
     #include "opentelemetry-matlab/exporters/otlp/OtlpHttpSpanExporterProxy.h"
+    #include "opentelemetry-matlab/exporters/otlp/OtlpHttpMetricExporterProxy.h"
 #endif
 #ifdef WITH_OTLP_GRPC
     #include "opentelemetry-matlab/exporters/otlp/OtlpGrpcSpanExporterProxy.h"
+    #include "opentelemetry-matlab/exporters/otlp/OtlpGrpcMetricExporterProxy.h"
 #endif
 
 libmexclass::proxy::MakeResult
 OtelMatlabProxyFactory::make_proxy(const libmexclass::proxy::ClassName& class_name,
                                const libmexclass::proxy::FunctionArguments& constructor_arguments) {
 
+    REGISTER_PROXY(libmexclass.opentelemetry.MeterProviderProxy, libmexclass::opentelemetry::MeterProviderProxy);
     REGISTER_PROXY(libmexclass.opentelemetry.TracerProviderProxy, libmexclass::opentelemetry::TracerProviderProxy);
     //REGISTER_PROXY(libmexclass.opentelemetry.TracerProxy, libmexclass::opentelemetry::TracerProxy);
     REGISTER_PROXY(libmexclass.opentelemetry.SpanProxy, libmexclass::opentelemetry::SpanProxy);
@@ -54,11 +60,18 @@ OtelMatlabProxyFactory::make_proxy(const libmexclass::proxy::ClassName& class_na
     REGISTER_PROXY(libmexclass.opentelemetry.sdk.AlwaysOffSamplerProxy, libmexclass::opentelemetry::sdk::AlwaysOffSamplerProxy);
     REGISTER_PROXY(libmexclass.opentelemetry.sdk.TraceIdRatioBasedSamplerProxy, libmexclass::opentelemetry::sdk::TraceIdRatioBasedSamplerProxy);
     REGISTER_PROXY(libmexclass.opentelemetry.sdk.ParentBasedSamplerProxy, libmexclass::opentelemetry::sdk::ParentBasedSamplerProxy);
+
+    REGISTER_PROXY(libmexclass.opentelemetry.sdk.MeterProviderProxy, libmexclass::opentelemetry::sdk::MeterProviderProxy);
+    REGISTER_PROXY(libmexclass.opentelemetry.sdk.ViewProxy, libmexclass::opentelemetry::sdk::ViewProxy);
+    REGISTER_PROXY(libmexclass.opentelemetry.sdk.PeriodicExportingMetricReaderProxy, libmexclass::opentelemetry::sdk::PeriodicExportingMetricReaderProxy);
+
     #ifdef WITH_OTLP_HTTP
         REGISTER_PROXY(libmexclass.opentelemetry.exporters.OtlpHttpSpanExporterProxy, libmexclass::opentelemetry::exporters::OtlpHttpSpanExporterProxy);
+        REGISTER_PROXY(libmexclass.opentelemetry.exporters.OtlpHttpMetricExporterProxy, libmexclass::opentelemetry::exporters::OtlpHttpMetricExporterProxy);
     #endif
     #ifdef WITH_OTLP_GRPC
         REGISTER_PROXY(libmexclass.opentelemetry.exporters.OtlpGrpcSpanExporterProxy, libmexclass::opentelemetry::exporters::OtlpGrpcSpanExporterProxy);
+        REGISTER_PROXY(libmexclass.opentelemetry.exporters.OtlpGrpcMetricExporterProxy, libmexclass::opentelemetry::exporters::OtlpGrpcMetricExporterProxy);
     #endif
     return nullptr;
 }

README.md

@@ -4,7 +4,8 @@
 MATLAB® interface to [OpenTelemetry™](https://opentelemetry.io/), based on the [OpenTelemetry Specification](https://opentelemetry.io/docs/reference/specification/). OpenTelemetry is an observability framework for creating and managing telemetry data, such as traces, metrics, and logs. This data can then be sent to an observability back-end for monitoring, alerts, and analysis. 
 
 ### Status
-- Currently only tracing is supported. Metrics and logs will be in the future.
+- Currently only tracing and metrics (synchronous instruments) are supported. Asynchronous metrics instruments and logs will be in the future.
+- View class in metrics is only partially supported. The properties **Aggregation** and **AllowedAttributes** are not yet supported. 
 - This package is supported and has been tested on Windows®, Linux®, and macOS.
 
 ### MathWorks Products (https://www.mathworks.com)
@@ -43,6 +44,7 @@ otelcol --config <otelcol-config-yaml>
 >> addpath <OpenTelemetry MATLAB installdir>
 ```
 ## Examples
+### Tracing
 1. Create a default tracer provider and save it.
 ```
 >> p = opentelemetry.sdk.trace.TracerProvider();
@@ -58,6 +60,22 @@ otelcol --config <otelcol-config-yaml>
 >> sp.endSpan();
 ```
 4. If your collector is configured to display the data, you should see your span displayed. 
+### Metrics
+1. Create a default meter provider and save it.
+```
+>> p = opentelemetry.sdk.metrics.MeterProvider();
+>> setMeterProvider(p);
+```
+2. Create a counter
+```
+>> m = opentelemetry.metrics.getMeter("First Meter");
+>> c = m.createCounter("FirstCounter");
+```
+3. Increment the counter
+```
+>> c.add(10);
+```
+4. If your collector is configured to display the data, you should see your counter displayed after 1 minute.
 
 For more examples, see the "examples" folder.
 

api/metrics/+opentelemetry/+metrics/Counter.m

@@ -0,0 +1,30 @@
+classdef Counter < opentelemetry.metrics.SynchronousInstrument
+    % Counter is a value that accumulates over time and can only increase
+    % but not decrease.
+
+    % Copyright 2023 The MathWorks, Inc.
+
+    methods (Access={?opentelemetry.metrics.Meter})
+        function obj = Counter(proxy, name, description, unit)
+            % Private constructor. Use createCounter method of Meter
+            % to create Counters.
+            [email protected](proxy, name, description, unit);
+        end
+    end
+
+    methods
+        function add(obj, value, varargin)
+            % ADD Add to counter value
+            %    ADD(C, VALUE) adds a nonnegative scalar numeric value to
+            %    the counter.
+            %
+            %    ADD(C, VALUE, ATTRIBUTES) also specifies attributes as a
+            %    dictionary
+            %
+            %    ADD(C, VALUE, ATTRNAME1, ATTRVALUE1, ATTRNAME2,
+            %    ATTRVALUE2, ...) specifies attributes as trailing
+            %    name-value pairs.
+            obj.processValue(value, varargin{:});
+        end
+    end
+end

api/metrics/+opentelemetry/+metrics/Histogram.m

@@ -0,0 +1,29 @@
+classdef Histogram < opentelemetry.metrics.SynchronousInstrument
+    % Histogram is an instrument that aggregates values into bins
+
+    % Copyright 2023 The MathWorks, Inc.
+
+    methods (Access={?opentelemetry.metrics.Meter})
+        function obj = Histogram(proxy, name, description, unit)
+            % Private constructor. Use createHistogram method of Meter
+            % to create Histograms.
+            [email protected](proxy, name, description, unit);
+        end
+    end
+
+    methods
+        function record(obj, value, varargin)
+            % RECORD Aggregate a value into a histogram bin
+            %    RECORD(H, VALUE) determine which bin VALUE falls into and
+            %    increment that bin by 1.
+            %
+            %    RECORD(H, VALUE, ATTRIBUTES) also specifies attributes as a
+            %    dictionary
+            %
+            %    RECORD(H, VALUE, ATTRNAME1, ATTRVALUE1, ATTRNAME2,
+            %    ATTRVALUE2, ...) specifies attributes as trailing
+            %    name-value pairs.
+            obj.processValue(value, varargin{:});
+        end
+    end
+end