Meter Interface

public abstract void close()

public abstract TelemetryAttributes createAttributes(Map attributeMap)

Creates and returns attribute collection implementation specific to the meter implementation. Attribute collections differ in how they support different types of attributes and internal data structures they use. For the best performance, client libraries should create and cache attribute collections for the client lifetime and pass cached instance when recoding new measurements.

// Create attributes for possible error codes. Can be done lazily once specific error code is received.
 TelemetryAttributes successAttributes = defaultMeter.createAttributes(new HashMap<String, Object>() {{
         put("endpoint", "http://service-endpoint.azure.com");
         put("error", true);
     }});

 TelemetryAttributes errorAttributes =  defaultMeter.createAttributes(new HashMap<String, Object>() {{
         put("endpoint", "http://service-endpoint.azure.com");
         put("error", false);
     }});

 LongCounter httpConnections = defaultMeter.createLongCounter("az.core.http.connections",
     "Number of created HTTP connections", null);

 boolean success = false;
 try {
     success = doThings();
 } finally {
     httpConnections.add(1, success ? successAttributes : errorAttributes, currentContext);
 }

Parameters:

Returns:

public abstract DoubleHistogram createDoubleHistogram(String name, String description, String unit)

Creates histogram instrument allowing to record long values. Histograms should be used for latency or other measurements where distribution of values is important and values are statistically bounded. See https://opentelemetry.io/docs/reference/specification/metrics/api/\#histogram for more details.

// Meter and instruments should be created along with service client instance and retained for the client
 // lifetime for optimal performance
 Meter meter = meterProvider
     .createMeter("azure-core", "1.0.0", new MetricsOptions());

 DoubleHistogram amqpLinkDuration = meter
     .createDoubleHistogram("az.core.amqp.link.duration", "AMQP link response time.", "ms");

 TelemetryAttributes attributes = defaultMeter.createAttributes(
     Collections.singletonMap("endpoint", "http://service-endpoint.azure.com"));

 // when measured operation starts, record the measurement
 Instant start = Instant.now();

 doThings();

 // optionally check if meter is operational for the best performance
 if (amqpLinkDuration.isEnabled()) {
     amqpLinkDuration.record(Instant.now().toEpochMilli() - start.toEpochMilli(), attributes, currentContext);
 }

Parameters:

Returns:

public abstract LongCounter createLongCounter(String name, String description, String unit)

Creates Counter instrument that is used to record incrementing values, such as number of sent messages or created connections. Use createLongUpDownCounter(String name, String description, String unit) for counters that can go down, such as number of active connections or queue size. See https://opentelemetry.io/docs/reference/specification/metrics/api/\#counter for more details.

TelemetryAttributes attributes = defaultMeter.createAttributes(new HashMap<String, Object>() {{
         put("endpoint", "http://service-endpoint.azure.com");
         put("status", "ok");
     }});

 LongCounter createdHttpConnections = defaultMeter.createLongCounter("az.core.http.connections",
     "Number of created HTTP connections", null);

 createdHttpConnections.add(1, attributes, currentContext);

Parameters:

Returns:

public default LongGauge createLongGauge(String name, String description, String unit)

Creates LongGauge instrument that is used to asynchronously record current value of metric. See https://opentelemetry.io/docs/reference/specification/metrics/api/\#asynchronous-gauge for more details.

TelemetryAttributes attributes = defaultMeter.createAttributes(new HashMap<String, Object>() {{
         put("endpoint", "http://service-endpoint.azure.com");
         put("container", "my-container");
     }});

 LongGauge latestSequenceNumber = defaultMeter.createLongGauge("az.eventhubs.consumer.sequence_number",
     "Sequence number of the latest event received from the broker.", null);

 AutoCloseable subscription = latestSequenceNumber.registerCallback(sequenceNumber::get, attributes);

 // update value when event is received
 sequenceNumber.set(getSequenceNumber());

 try {
     subscription.close();
 } catch (Exception e) {
     e.printStackTrace();
 }

Parameters:

Returns:

public abstract LongCounter createLongUpDownCounter(String name, String description, String unit)

Creates UpDownCounter instrument that is used to record values that can go up or down, such as number of active connections or queue size. See https://opentelemetry.io/docs/reference/specification/metrics/api/\#updowncounter for more details.

TelemetryAttributes attributes = defaultMeter.createAttributes(new HashMap<String, Object>() {{
         put("endpoint", "http://service-endpoint.azure.com");
         put("status", "ok");
     }});

 LongCounter activeHttpConnections = defaultMeter.createLongUpDownCounter("az.core.http.active.connections",
     "Number of active HTTP connections", null);

 // on connection initialized:
 activeHttpConnections.add(1, attributes, currentContext);

 // on connection closed:
 activeHttpConnections.add(-1, attributes, currentContext);

Parameters:

Returns:

public abstract boolean isEnabled()

Checks if Meter implementation was found, and it's enabled.

Returns: