public void collectMetrics()

in src/main/java/org/opensearch/performanceanalyzer/collectors/CacheConfigMetricsCollector.java [72:141]
63 lines of code
4 McCabe index (conditional complexity)

    public void collectMetrics(long startTime) {
        IndicesService indicesService = OpenSearchResources.INSTANCE.getIndicesService();
        if (indicesService == null) {
            return;
        }

        value.setLength(0);
        value.append(PerformanceAnalyzerMetrics.getJsonCurrentMilliSeconds());
        // This is for backward compatibility. Core OpenSearch may or may not emit maxWeight metric.
        // (depending on whether the patch has been applied or not). Thus, we need to use
        // reflection to check whether getMaxWeight() method exist in Cache.java
        //
        // Currently, we are collecting maxWeight metrics only for FieldData and Shard Request
        // Cache.
        CacheMaxSizeStatus fieldDataCacheMaxSizeStatus =
                AccessController.doPrivileged(
                        (PrivilegedAction<CacheMaxSizeStatus>)
                                () -> {
                                    try {
                                        Cache fieldDataCache =
                                                indicesService
                                                        .getIndicesFieldDataCache()
                                                        .getCache();
                                        long fieldDataMaxSize =
                                                (Long)
                                                        FieldUtils.readField(
                                                                fieldDataCache,
                                                                CACHE_MAX_WEIGHT,
                                                                true);
                                        return new CacheMaxSizeStatus(
                                                FIELD_DATA_CACHE.toString(), fieldDataMaxSize);
                                    } catch (Exception e) {
                                        return new CacheMaxSizeStatus(
                                                FIELD_DATA_CACHE.toString(), null);
                                    }
                                });
        value.append(PerformanceAnalyzerMetrics.sMetricNewLineDelimitor)
                .append(fieldDataCacheMaxSizeStatus.serialize());
        CacheMaxSizeStatus shardRequestCacheMaxSizeStatus =
                AccessController.doPrivileged(
                        (PrivilegedAction<CacheMaxSizeStatus>)
                                () -> {
                                    try {
                                        Object reqCache =
                                                FieldUtils.readField(
                                                        indicesService,
                                                        "indicesRequestCache",
                                                        true);
                                        Cache requestCache =
                                                (Cache)
                                                        FieldUtils.readField(
                                                                reqCache, "cache", true);
                                        Long requestCacheMaxSize =
                                                (Long)
                                                        FieldUtils.readField(
                                                                requestCache,
                                                                CACHE_MAX_WEIGHT,
                                                                true);
                                        return new CacheMaxSizeStatus(
                                                SHARD_REQUEST_CACHE.toString(),
                                                requestCacheMaxSize);
                                    } catch (Exception e) {
                                        return new CacheMaxSizeStatus(
                                                SHARD_REQUEST_CACHE.toString(), null);
                                    }
                                });
        value.append(PerformanceAnalyzerMetrics.sMetricNewLineDelimitor)
                .append(shardRequestCacheMaxSizeStatus.serialize());
        saveMetricValues(value.toString(), startTime);
    }