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   <T extends Metric> T metric(T metric);

   void longMetric(String name, LongSupplier valueSupplier, @Nullable String description);

   LongConsumer longMetric(String name, @Nullable String description);

   void doubleMetric(String name, DoubleSupplier valueSupplier, @Nullable String description);

   DoubleConsumer doubleMetric(String name, @Nullable String description);

   void booleanMetric(String name, BooleanSupplier valueSupplier, @Nullable String description);

   Consumer<Boolean> booleanMetric(String name, @Nullable String description);

   <T> void objectMetric(String name, Class<T> valueType, Supplier<T> valueSupplier, @Nullable String description);

   <T> Consumer<T> objectMetric(String name, Class<T> valueType, @Nullable String description);

   void removeMetric(String name);

   ReadOnlyMetricRegistry registry(String name);
}

Risks and Assumptions

    Custom metrics can affect the performance.

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Phases

1. Implementation of the described API.
2. Extending the API with metrics like Histogram, HitRate. Allowing to configure metrics.
3. Storing registered custom metrics with their configurations.

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