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- [ ] I have searched the [issues](https://github.com/apache/dubbo/issues) of this repository and believe that this is not a duplicate.

## Describe the proposal
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@wxbty PTAL
import org.apache.dubbo.metrics.listener.AbstractMetricsListener;
import org.apache.dubbo.metrics.model.MethodMetric;
import org.apache.dubbo.metrics.model.key.MetricsKey;
import org.apache.dubbo.metrics.model.sample.MetricSample;
import org.apache.dubbo.metrics.register.HistogramMetricRegister;
import org.apache.dubbo.metrics.sample.HistogramMetricSample;
import org.apache.dubbo.rpc.model.ApplicationModel;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.TimeUnit;
import static org.apache.dubbo.metrics.model.MetricsCategory.RT;
public class HistogramMetricsCollector extends AbstractMetricsListener<RequestEvent> implements MetricsCollector<RequestEvent> {
    private final ConcurrentHashMap<MethodMetric, Timer> rt = new ConcurrentHashMap<>();
    private HistogramMetricRegister metricRegister;
    private final ApplicationModel applicationModel;
    private static final Integer[] DEFAULT_BUCKETS_MS = new Integer[]{100, 300, 500, 1000, 3000, 5000, 10000};
    public HistogramMetricsCollector(ApplicationModel applicationModel) {
        this.applicationModel = applicationModel;
        ConfigManager configManager = applicationModel.getApplicationConfigManager();
        MetricsConfig config = configManager.getMetrics().orElse(null);
        if (config != null && config.getHistogram() != null && Boolean.TRUE.equals(config.getHistogram().getEnabled())) {
            registerListener();
            HistogramConfig histogram = config.getHistogram();
            if (!Boolean.TRUE.equals(histogram.getEnabledPercentiles()) && histogram.getBucketsMs() == null) {
                histogram.setBucketsMs(DEFAULT_BUCKETS_MS);
            }
            metricRegister = new HistogramMetricRegister(MetricsGlobalRegistry.getCompositeRegistry(applicationModel), histogram);
        }
    }