NoopStatsContextFactory.java

/*
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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package com.linecorp.armeria.server.grpc.interop;

import java.io.InputStream;
import java.io.OutputStream;

import com.google.instrumentation.stats.MeasurementMap;
import com.google.instrumentation.stats.StatsContext;
import com.google.instrumentation.stats.StatsContextFactory;
import com.google.instrumentation.stats.TagKey;
import com.google.instrumentation.stats.TagValue;

final class NoopStatsContextFactory extends StatsContextFactory {

    private static final StatsContext DEFAULT_CONTEXT = new NoopStatsContext();
    private static final StatsContext.Builder BUILDER = new NoopContextBuilder();

    public static final StatsContextFactory INSTANCE = new NoopStatsContextFactory();

    private NoopStatsContextFactory() {
    }

    @Override
    public StatsContext deserialize(InputStream is) {
        return DEFAULT_CONTEXT;
    }

    @Override
    public StatsContext getDefault() {
        return DEFAULT_CONTEXT;
    }

    private static class NoopStatsContext extends StatsContext {
        @Override
        public Builder builder() {
            return BUILDER;
        }

        @Override
        public StatsContext record(MeasurementMap metrics) {
            return DEFAULT_CONTEXT;
        }

        @Override
        public void serialize(OutputStream os) {}
    }

    private static class NoopContextBuilder extends StatsContext.Builder {
        @Override
        public StatsContext.Builder set(TagKey key, TagValue value) {
            return this;
        }

        @Override
        public StatsContext build() {
            return DEFAULT_CONTEXT;
        }
    }
}