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package org.apache.ignite;

public interface IgniteMetrics {
    <T extends Metric> T metric(T metric);

    @Nullable <T extends Metric> T metric(String name);

    void removeMetric(String name);

    ReadOnlyMetricRegistry registry(String name);

    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);
}

Risks and Assumptions

• User should take in account that Custom metrics can affect the performance. 
• Ignite doesn't store custom metrics. At least at the first phase. After node restart, the metrics require registration anew.

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