objc-class-tree can print a nice tree of Objective-C classes.
By default, it will print a huge tree of all the classes loaded in its own binary:
$ objc-class-tree | head -30
NSProxy
_NSZombie_
__NSMessageBuilder
__NSGenericDeallocHandler
Object
NSObject
+-- OCTMethod
+-- OCTTreeFormatter
+-- NSURLDownload
+-- NSXPCInterface
+-- NSAppleEventDescriptor
+-- NSFileWrapper
| +-- NSFileWrapperLink
| +-- NSFileWrapperDirectory
| +-- NSFileWrapperFile
+-- NSURLSessionConfiguration
+-- NSSpellEngine
+-- NSXMLParser
+-- NSXMLNode
| +-- NSXMLElement
| +-- NSXMLDTDNode
| +-- NSXMLDTD
| +-- NSXMLDocument
+-- NSValueTransformer
| +-- _NSSharedValueTransformer
| +-- _NSUnarchiveFromDataTransformer
| +-- _NSKeyedUnarchiveFromDataTransformer
| +-- _NSNegateBooleanTransformer
| +-- _NSIsNotNilTransformer
| +-- _NSIsNilTransformer
$ objc-class-tree | wc -l
401
You can limit its output to a handful of class trees by using the --root-class option:
$ objc-class-tree --root-class NSArray --root-class NSXMLNode
NSArray
+-- NSKeyValueArray
+-- __NSOrderedSetArrayProxy
+-- __NSArrayI
+-- NSMutableArray
+-- NSKeyValueMutableArray
| +-- NSKeyValueNotifyingMutableArray
| +-- NSKeyValueIvarMutableArray
| +-- NSKeyValueFastMutableArray
| | +-- NSKeyValueFastMutableArray2
| | +-- NSKeyValueFastMutableArray1
| +-- NSKeyValueSlowMutableArray
+-- __NSPlaceholderArray
+-- __NSCFArray
NSXMLNode
+-- NSXMLElement
+-- NSXMLDTDNode
+-- NSXMLDTD
+-- NSXMLDocument
You can ask it to output implemented methods:
$ objc-class-tree --root-class NSURLResponse --methods
NSURLResponse
+-- - init
+-- - dealloc
+-- - copyWithZone:
+-- - initWithCoder:
+-- - encodeWithCoder:
+-- - URL
+-- - _CFURLResponse
+-- - _initWithCFURLResponse:
+-- - initWithURL:MIMEType:expectedContentLength:textEncodingName:
+-- - suggestedFilename
+-- - expectedContentLength
+-- - textEncodingName
+-- - MIMEType
+-- + _responseWithCFURLResponse:
+-- NSHTTPURLResponse
+-- - initWithCoder:
+-- - statusCode
+-- - _initWithCFURLResponse:
+-- - initWithURL:statusCode:HTTPVersion:headerFields:
+-- - initWithURL:statusCode:headerFields:requestTime:
+-- - _peerTrust
+-- - _setPeerTrust:
+-- - _clientCertificateState
+-- - _clientCertificateChain
+-- - _peerCertificateChain
+-- - allHeaderFields
+-- + supportsSecureCoding
+-- + isErrorStatusCode:
+-- + localizedStringForStatusCode:
It can also display protocols and which libraries the classes come from:
$ objc-class-tree --root-class NSString --protocols --library-names
NSString (Foundation)
+-- NSSimpleCString (Foundation)
| +-- NSConstantString (Foundation)
+-- NSPathStore2 (Foundation)
+-- NSLocalizableString (Foundation)
+-- NSPlaceholderString (Foundation)
+-- NSMutableString (Foundation)
+-- NSPlaceholderMutableString (Foundation)
+-- NSMutableStringProxyForMutableAttributedString (Foundation)
+-- __NSCFString (CoreFoundation)
+-- __NSCFConstantString (CoreFoundation)
See main.m for more supported options.
Building
Build using Meson as usual:
$ meson build
$ cd build
$ ninja build
# optionally
$ sudo ninja install
$ cd build
$ ninja build
# optionally
$ sudo ninja install
License
objc-class-tree is free software, available under the GNU General Public License version 3 or later.