public static Map<String, Double> measureAll(MeterRegistry registry) {
        requireNonNull(registry, "registry");

        final ImmutableMap.Builder<String, Double> builder = ImmutableMap.builder();

        registry.forEachMeter(meter -> Streams.stream(meter.measure()).forEach(measurement -> {
            final String fullName = measurementName(meter.getId(), measurement);
            final double value = measurement.getValue();
            builder.put(fullName, value);
        }));

        return builder.build();
    }
Returns a newly-created immutable {@link Map} which contains all values of {@link Meter}s in the
specified {@link MeterRegistry}. The format of the key string is:
<ul>
  <li>{@code <name>#<statistic>{tagName=tagValue,...}}</li>
  <li>e.g. {@code "armeria.server.active.requests#value{method=greet}"}</li>
  <li>e.g. {@code "some.subsystem.some.value#count"} (no tags)</li>
</ul>
Note: It is not recommended to use this method for the purposes other than testing.
core/src/main/java/com/linecorp/armeria/common/metric/MoreMeters.java