private List<TraceMetadataProvider> fromServiceLoader(ClassLoader classLoader) {
        List<TraceMetadataProvider> traceMetadataProviders = new ArrayList<>();
        ServiceLoader<TraceMetadataProvider> serviceLoader = ServiceLoader.load(TraceMetadataProvider.class, classLoader);
        for (TraceMetadataProvider traceMetadataProvider : serviceLoader) {
            traceMetadataProviders.add(new LoadedTraceMetadataProvider(traceMetadataProvider));
        }
        return traceMetadataProviders;
    }
@author HyunGil Jeong
@author Taejin Koo
agent-module/plugins-loader/src/main/java/com/navercorp/pinpoint/loader/plugins/trace/TraceMetadataProviderLoader.java