public void initProviders()

in meecrowave-core/src/main/java/org/apache/meecrowave/cxf/ConfigurableBus.java [80:148]
64 lines of code
5 McCabe index (conditional complexity)

    public void initProviders(final Configuration builder,
                              final ClassLoader loader) {
        final List<Object> providers =
                ofNullable(builder.getJaxrsDefaultProviders())
                        .map(s -> Stream.of(s.split(" *, *"))
                                .map(String::trim)
                                .filter(p -> !p.isEmpty())
                                .map(name -> {
                                    try {
                                        return Thread.currentThread().getContextClassLoader().loadClass(name).newInstance();
                                    } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) {
                                        throw new IllegalArgumentException(name + " can't be created");
                                    }
                                })
                                .collect(Collectors.<Object>toList()))
                        .orElseGet(() -> {
                            // ensure both providers share the same memory reuse logic
                            final JsonProvider provider = JsonProvider.provider();
                            final JsonReaderFactory readerFactory = provider.createReaderFactory(
                                    new HashMap<String, Object>() {{
                                        put(JsonParserFactoryImpl.SUPPORTS_COMMENTS, builder.isJsonpSupportsComment());
                                        Optional.of(builder.getJsonpMaxStringLen()).filter(v -> v > 0)
                                                .ifPresent(s -> put(JsonParserFactoryImpl.MAX_STRING_LENGTH,
                                                        s));
                                        Optional.of(builder.getJsonpMaxReadBufferLen()).filter(v -> v > 0)
                                                .ifPresent(s -> put(JsonParserFactoryImpl.BUFFER_LENGTH,
                                                        s));
                                        ofNullable(builder.getJsonpBufferStrategy()).ifPresent(
                                                s -> put(AbstractJsonFactory.BUFFER_STRATEGY, s));
                                    }});
                            final JsonWriterFactory writerFactory = provider.createWriterFactory(
                                    new HashMap<String, Object>() {{
                                        put(JsonGenerator.PRETTY_PRINTING, builder.isJsonpPrettify());
                                        Optional.of(builder.getJsonpMaxWriteBufferLen()).filter(v -> v > 0)
                                                .ifPresent(v -> put(
                                                        JsonGeneratorFactoryImpl
                                                                .GENERATOR_BUFFER_LENGTH,
                                                        v));
                                        ofNullable(builder.getJsonpBufferStrategy()).ifPresent(
                                                s -> put(AbstractJsonFactory.BUFFER_STRATEGY, s));
                                    }});
                            return Stream.<Object>of(
                                    new ConfiguredJsonbJaxrsProvider(
                                            builder.getJsonbEncoding(), builder.isJsonbNulls(),
                                            builder.isJsonbIJson(), builder.isJsonbPrettify(),
                                            builder.getJsonbBinaryStrategy(), builder.getJsonbNamingStrategy(),
                                            builder.getJsonbOrderStrategy(),
                                            new DelegateJsonProvider(provider, readerFactory, writerFactory)))
                                    .collect(toList());
                        });

        if (builder.isJaxrsAutoActivateBeanValidation()) {
            try { // we don't need the jaxrsbeanvalidationfeature since bean validation cdi extension handles it normally
                loader.loadClass("javax.validation.Validation");
                final Object instance = loader.loadClass("org.apache.cxf.jaxrs.validation.ValidationExceptionMapper")
                        .getConstructor().newInstance();
                instance.getClass().getGenericInterfaces(); // validate bval can be used, check NoClassDefFoundError javax.validation.ValidationException
                providers.add(instance);
            } catch (final Exception | NoClassDefFoundError e) {
                // no-op
            }
        }

        // client
        if (getProperty("org.apache.cxf.jaxrs.bus.providers") == null) {
            setProperty("skip.default.json.provider.registration", "true");
            setProperty("org.apache.cxf.jaxrs.bus.providers", providers);
        }
    }