• There are 215 files with units, with 18,752 lines of code.
• 0 very complex files (McCabe index sum 251+; 0 lines of code)
• 2 complex files (McCabe index sum 126-250; 1,353 lines of code)
• 10 medium complex files (McCabe index sum 51-125; 3,838 lines of code)
• 21 slightly complex files (McCabe index sum 26-50; 3,971 lines of code)
• 182 simple files (McCabe index sum 1-25; 9,590 lines of code)
• 45 main files have no units (e.g. languages without unit analysis, or files without functions) and are not classified.

The McCabe index of a file grows with its size: per 100 lines tells a large but plain file from a dense one, and most complex unit whether the complexity sits in one unit or is spread over many.

File	# lines	# units	McCabe index (sum)	per 100 lines	most complex unit
ProxyEndpoint.java in zuul-core/src/main/java/com/netflix/zuul/filters/endpoint	863	61	160	19	11
Headers.java in zuul-core/src/main/java/com/netflix/zuul/message	490	66	128	26	6
HttpRequestMessageImpl.java in zuul-core/src/main/java/com/netflix/zuul/message/http	547	60	105	19	8
CurrentPassport.java in zuul-core/src/main/java/com/netflix/zuul/passport	389	38	95	24	9
HeaderHandoffBenchmark.java in zuul-core/src/jmh/java/com/netflix/zuul/netty	457	34	86	19	14
RequestAttempt.java in zuul-core/src/main/java/com/netflix/zuul/niws	307	41	72	23	11
SessionContext.java in zuul-core/src/main/java/com/netflix/zuul/context	322	62	70	22	2
BaseZuulFilterRunner.java in zuul-core/src/main/java/com/netflix/zuul/netty/filter	373	28	70	19	6
ClientRequestReceiver.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	393	17	69	18	16
PerServerConnectionPool.java in zuul-core/src/main/java/com/netflix/zuul/netty/connectionpool	372	28	60	16	6
ZuulToNettyHttpHeaders.java in zuul-core/src/main/java/com/netflix/zuul/netty	286	34	53	19	4
Server.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	392	20	51	13	7
ClientResponseWriter.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	240	13	50	21	13
HttpQueryParams.java in zuul-core/src/main/java/com/netflix/zuul/message/http	186	23	48	26	9
DefaultClientChannelManager.java in zuul-core/src/main/java/com/netflix/zuul/netty/connectionpool	350	28	47	13	7
OriginResponseReceiver.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	237	15	46	19	11
SslHandshakeInfoHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/ssl	254	6	44	17	27
DiscoveryResult.java in zuul-discovery/src/main/java/com/netflix/zuul/discovery	167	34	44	26	5
HttpResponseMessageImpl.java in zuul-core/src/main/java/com/netflix/zuul/message/http	197	35	41	21	3
ZuulMessageImpl.java in zuul-core/src/main/java/com/netflix/zuul/message	190	22	40	21	6
PooledConnection.java in zuul-core/src/main/java/com/netflix/zuul/netty/connectionpool	165	28	36	22	6
DynamicHttp2FrameLogger.java in zuul-core/src/main/java/com/netflix/netty/common/http2	224	19	35	16	3
HttpUtils.java in zuul-core/src/main/java/com/netflix/zuul/util	137	13	35	26	5
ZuulEndPointRunner.java in zuul-core/src/main/java/com/netflix/zuul/netty/filter	187	13	33	18	9
ZuulPskServer.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/psk	194	16	32	16	5
BasicNettyOrigin.java in zuul-core/src/main/java/com/netflix/zuul/origins	182	25	32	18	4
PushRegistrationHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/push	159	14	30	19	7
BaseSslContextFactory.java in zuul-core/src/main/java/com/netflix/zuul/netty/ssl	177	14	28	16	7
PushMessageSender.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/push	142	13	28	20	13
ZuulFilterChainRunner.java in zuul-core/src/main/java/com/netflix/zuul/netty/filter	135	6	27	20	18
ZuulFilterChainHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/filter	145	9	27	19	6
RejectionUtils.java in zuul-core/src/main/java/com/netflix/netty/common/throttle	199	9	26	13	10
AccessLogPublisher.java in zuul-core/src/main/java/com/netflix/netty/common/accesslog	104	4	26	25	21
BaseConnectionCloseHandler.java in zuul-core/src/main/java/com/netflix/netty/common/close	117	10	25	21	5
BaseServerStartup.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	305	19	25	8	3
BaseZuulChannelInitializer.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	289	17	24	8	4
HttpBodySizeRecordingChannelHandler.java in zuul-core/src/main/java/com/netflix/netty/common/metrics	100	11	21	21	4
ConnectionPoolHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/connectionpool	125	9	21	17	8
Http2ContentLengthEnforcingHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/http2	67	7	20	30	7
GZipResponseFilter.java in zuul-core/src/main/java/com/netflix/zuul/filters/common	97	6	19	20	10
PassportLoggingHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/insights	115	5	19	17	12
Http2MetricsChannelHandlers.java in zuul-core/src/main/java/com/netflix/netty/common/metrics	117	10	18	15	3
BaseFilter.java in zuul-core/src/main/java/com/netflix/zuul/filters	90	15	18	20	3
ClientConnectionsShutdown.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	117	5	18	15	7
ConnectionPoolConfigImpl.java in zuul-core/src/main/java/com/netflix/zuul/netty/connectionpool	110	18	18	16	1
StatusCategoryUtils.java in zuul-core/src/main/java/com/netflix/zuul/stats/status	68	14	18	26	4
Http1FramingEnforcingHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server	73	4	17	23	11
PushAuthHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/push	94	5	17	18	7
ConnCounter.java in zuul-core/src/main/java/com/netflix/zuul/monitoring	100	8	17	17	4
Http2OrHttpHandler.java in zuul-core/src/main/java/com/netflix/zuul/netty/server/http2	143	6	16	11	7

• File complexity is the sum of the McCabe indexes (conditional complexity) of the units (methods, functions...) in a file.
• Files are classified in five categories based on that sum: 1-25 (simple files), 26-50 (slightly complex files), 51-125 (medium complex files), 126-250 (complex files), 251+ (very complex files). The default bands are five times the unit complexity bands, as a file is a group of units.
• Only main code files with units are classified. Files without units (languages without unit analysis, or files without functions) have no complexity to measure and are left out rather than counted as simple.
• A very complex file holds many decisions, which often means it has too many responsibilities: a candidate to split, and a place where changes need more testing.