888:. Overriding introduces a complication: which version of the behavior does an instance of the inherited class use—the one that is part of its own class, or the one from the parent (base) class? The answer varies between programming languages, and some languages provide the ability to indicate that a particular behavior is not to be overridden and should behave as defined by the base class. For instance, in C#, the base method or property can only be overridden in a subclass if it is marked with the virtual, abstract, or override modifier, while in programming languages such as Java, different methods can be called to override other methods. An alternative to overriding is
1707:. When inheritance was used as a primary approach to structure programs in the late 1990s, developers tended to break code into more layers of inheritance as the system functionality grew. If a development team combined multiple layers of inheritance with the single responsibility principle, this resulted in many very thin layers of code, with many layers consisting of only 1 or 2 lines of actual code. Too many layers make debugging a significant challenge, as it becomes hard to determine which layer needs to be debugged.
871:
945:
338:
279:
271:
757:. Some languages require that method be specifically declared as virtual (e.g. C++), and in others, all methods are virtual (e.g. Java). An invocation of a non-virtual method will always be statically dispatched (i.e. the address of the function call is determined at compile-time). Static dispatch is faster than dynamic dispatch and allows optimizations such as
36:
1308:
relationship between the subtype and some existing abstraction, either implicitly or explicitly, depending on language support. The relationship can be expressed explicitly via inheritance in languages that support inheritance as a subtyping mechanism. For example, the following C++ code establishes
1279:
Another frequent use of inheritance is to guarantee that classes maintain a certain common interface; that is, they implement the same methods. The parent class can be a combination of implemented operations and operations that are to be implemented in the child classes. Often, there is no interface
316:
actually claimed that adding multiple inheritance to C++ was impossible. Thus, multiple inheritance seemed more of a challenge. Since I had considered multiple inheritance as early as 1982 and found a simple and efficient implementation technique in 1984, I couldn't resist the challenge. I suspect
241:
presented a design that allowed specifying objects that belonged to different classes but had common properties. The common properties were collected in a superclass, and each superclass could itself potentially have a superclass. The values of a subclass were thus compound objects, consisting of
1638:
is an alternative to inheritance. This technique supports polymorphism and code reuse by separating behaviors from the primary class hierarchy and including specific behavior classes as required in any business domain class. This approach avoids the static nature of a class hierarchy by allowing
1581:. However, in most implementations, it can still inherit from each superclass only once, and thus, does not support cases in which a student has two jobs or attends two institutions. The inheritance model available in Eiffel makes this possible through support for
616:
that define the specification of a class are also inherited by heirs. The superclass establishes a common interface and foundational functionality, which specialized subclasses can inherit, modify, and supplement. The software inherited by a subclass is considered
188:
relationship, whereas inheritance only reuses implementation and establishes a syntactic relationship, not necessarily a semantic relationship (inheritance does not ensure behavioral subtyping). To distinguish these concepts, subtyping is sometimes referred to as
242:
some number of prefix parts belonging to various superclasses, plus a main part belonging to the subclass. These parts were all concatenated together. The attributes of a compound object would be accessible by dot notation. This idea was first adopted in the
1695:
has spoken against implementation inheritance, stating that he would not include it if he were to redesign Java. Language designs that decouple inheritance from subtyping (interface inheritance) appeared as early as 1990; a modern example of this is the
1680:: modifications to the base class implementation can cause inadvertent behavioral changes in subclasses. Using interfaces avoids this problem because no implementation is shared, only the API. Another way of stating this is that "inheritance breaks
496:
Hybrid inheritance is when a mix of two or more of the above types of inheritance occurs. An example of this is when a class A has a subclass B which has two subclasses, C and D. This is a mixture of both multilevel inheritance and hierarchal
1275:
without substitutability. Whereas public inheritance represents an "is-a" relationship and delegation represents a "has-a" relationship, private (and protected) inheritance can be thought of as an "is implemented in terms of" relationship.
232:
presented some remarks on records, and in particular presented the idea of record subclasses, record types with common properties but discriminated by a variant tag and having fields private to the variant. Influenced by this, in 1967
931:
between two integers. The subclass re-uses all of the functionality of the base class with the exception of the operation that transforms a number into its square, replacing it with an operation that transforms a number into its
724:
Just as classes may be non-subclassable, method declarations may contain method modifiers that prevent the method from being overridden (i.e. replaced with a new function with the same name and type signature in a subclass). A
489:
This is where one class serves as a superclass (base class) for more than one sub class. For example, a parent class, A, can have two subclasses B and C. Both B and C's parent class is A, but B and C are two separate
1629:
superclass. Many modern languages, including C++ and Java, provide a "protected" access modifier that allows subclasses to access the data, without allowing any code outside the chain of inheritance to access
162:
of its parent class or super class. The term "inheritance" is loosely used for both class-based and prototype-based programming, but in narrow use the term is reserved for class-based programming (one class
625:. A uniform interface is used to invoke the member functions of objects of a number of different classes. Subclasses may replace superclass functions with entirely new functions that must share the same
60:
1516:.) In some OOP languages, the notions of code reuse and subtyping coincide because the only way to declare a subtype is to define a new class that inherits the implementation of another.
1263:
In most quarters, class inheritance for the sole purpose of code reuse has fallen out of favor. The primary concern is that implementation inheritance does not provide any assurance of
684:
that references or pointers to objects of that class are actually referencing instances of that class and not instances of subclasses (they do not exist) or instances of superclasses (
621:
in the subclass. A reference to an instance of a class may actually be referring to one of its subclasses. The actual class of the object being referenced is impossible to predict at
1617:
Whenever client code has access to an object, it generally has access to all the object's superclass data. Even if the superclass has not been declared public, the client can still
143:
of the base class. Inheritance allows programmers to create classes that are built upon existing classes, to specify a new implementation while maintaining the same behaviors (
1710:
Another issue with inheritance is that subclasses must be defined in code, which means that program users cannot add new subclasses at runtime. Other design patterns (such as
1500:, the relationship between a base class and a derived class is only a relationship between implementations (a mechanism for code reuse), as compared to a relationship between
769:
The following table shows which variables and functions get inherited dependent on the visibility given when deriving the class, using the terminology established by C++.
333:
where a subclass is inherited from another subclass. It is not uncommon that a class is derived from another derived class as shown in the figure "Multilevel inheritance".
177:
another). Class-modifying inheritance patterns can be pre-defined according to simple network interface parameters such that inter-language compatibility is preserved.
1647:
Implementation inheritance is controversial among programmers and theoreticians of object-oriented programming since at least the 1990s. Among them are the authors of
1995:. Proceedings of the 12th European Conference on Object-Oriented Programming (ECOOP). Lecture Notes in Computer Science. Vol. 1445. Springer. pp. 355–382.
1639:
behavior modifications at run time and allows one class to implement behaviors buffet-style, instead of being restricted to the behaviors of its ancestor classes.
879:
2117:
1267:
substitutability—an instance of the reusing class cannot necessarily be substituted for an instance of the inherited class. An alternative technique, explicit
729:
method is un-overridable simply because it is not accessible by classes other than the class it is a member function of (this is not true for C++, though). A
1681:
1264:
726:
2407:
2077:
1987:
132:
193:(without acknowledging that the specialization of type variables also induces a subtyping relation), whereas inheritance as defined here is known as
1508:. It is entirely possible to derive a class whose object will behave incorrectly when used in a context where the parent class is expected; see the
169:
131:, an object created through inheritance, a "child object", acquires all the properties and behaviors of the "parent object", with the exception of:
882:
permit a class or object to replace the implementation of an aspect—typically a behavior—that it has inherited. This process is called
148:
2097:
1764:
2493:
2382:
2289:
2261:
2136:
2060:
2008:
2557:
2480:. REX School/Workshop on the Foundations of Object-Oriented Languages. Lecture Notes in Computer Science. Vol. 489. pp. 60–90.
1688:, where client code is expected to inherit from system-supplied classes and then substituted for the system's classes in its algorithms.
1653:, who advocate interface inheritance instead, and favor composition over inheritance. For example, the decorator pattern (as mentioned
1657:) has been proposed to overcome the static nature of inheritance between classes. As a more fundamental solution to the same problem,
2184:
2039:
2525:
2346:
2225:
1946:
78:
1625:'s grade point average and transcript without also giving that function access to all of the personal data stored in the student's
1711:
2536:
1758:
1673:
1271:, requires more programming effort, but avoids the substitutability issue. In C++ private inheritance can be used as a form of
584:
The colon indicates that the subclass inherits from the superclass. The visibility is optional and, if present, may be either
1877:
1810:
688:
a reference type violates the type system). Because the exact type of the object being referenced is known before execution,
1504:. Inheritance, even in programming languages that support inheritance as a subtyping mechanism, does not necessarily entail
541:). The semantics of class inheritance vary from language to language, but commonly the subclass automatically inherits the
1967:
1509:
609:
259:
2047:. ECOOP 2013–Object-Oriented Programming. Lecture Notes in Computer Science. Vol. 7920. Springer. pp. 577–601.
184:. In some languages inheritance and subtyping agree, whereas in others they differ; in general, subtyping establishes an
1923:. Proceedings of the 17th ACM SIGPLAN-SIGACT Symposium on Principles of Programming Languages (POPL). pp. 125–135.
1814:
1779:
638:
213:
104:
308:... was widely supposed to be very difficult to implement efficiently. For example, in a summary of C++ in his book on
51:
1595:
when the object's type is selected and does not change with time. For example, the inheritance graph does not allow a
1592:
255:
108:
92:
1729:
1550:
In defining this inheritance hierarchy we have already defined certain restrictions, not all of which are desirable:
904:
code in a base class. By default the subclass retains all of the operations of the base class, but the subclass may
1280:
change between the supertype and subtype- the child implements the behavior described instead of its parent class.
1773:
1697:
1658:
1635:
1557:
Using single inheritance, a subclass can inherit from only one superclass. Continuing the example given above, a
100:
2434:
2411:
1611:.) Some have criticized inheritance, contending that it locks developers into their original design standards.
2014:
1513:
112:
1839:
2446:
1924:
1618:
293:
where subclasses inherit the features of one superclass. A class acquires the properties of another class.
152:
2562:
1740:
1862:
Conference proceedings on Object-oriented programming systems, languages and applications - OOPSLA '89
127:
and then forming them into a hierarchy of classes. In most class-based object-oriented languages like
1734:
1505:
1497:
889:
709:
705:
526:
136:
1929:
1531:
that contains a person's name, date of birth, address and phone number. We can define a subclass of
642:
46:
2451:
2253:
1785:
1569:, but not both. Using multiple inheritance partially solves this problem, as one can then define a
522:
1621:
the object to its superclass type. For example, there is no way to give a function a pointer to a
940:
respectively. The subclasses therefore compute the sum of the squares/cubes between two integers.
2146:
1883:
1703:
Complex inheritance, or inheritance used within an insufficiently mature design, may lead to the
1685:
1677:
1268:
713:
613:
205:
124:
870:
2374:
299:
where one class can have more than one superclass and inherit features from all parent classes.
167:
another), with the corresponding technique in prototype-based programming being instead called
2521:
2489:
2378:
2342:
2285:
2257:
2221:
2213:
2132:
2056:
2004:
1942:
1873:
1746:
1723:
1608:
905:
884:
865:
542:
322:
2481:
2456:
2366:
2362:
2245:
2124:
2048:
1996:
1934:
1865:
758:
754:
701:
626:
1860:
Madsen, OL (1989). "Virtual classes: A powerful mechanism in object-oriented programming".
17:
2277:
2241:
2192:
2170:
2158:
1649:
1582:
1539:
that contains the person's grade point average and classes taken, and another subclass of
693:
546:
238:
201:. Still, inheritance is a commonly used mechanism for establishing subtype relationships.
140:
2246:
2304:
2513:
750:
337:
234:
116:
147:), to reuse code and to independently extend original software via public classes and
2551:
2475:
2367:
1704:
1692:
1672:, the main problem with implementation inheritance is that it introduces unnecessary
933:
928:
689:
665:
keyword and the class identifier declaration. Such non-subclassable classes restrict
144:
2105:. IFIP Working Conference on Simulation Languages. Oslo: Norwegian Computing Center.
278:
1887:
937:
697:
681:
650:
622:
1805:
This is generally true only in statically-typed class-based OO languages, such as
1524:
Using inheritance extensively in designing a program imposes certain constraints.
270:
2052:
608:
Some languages also support the inheritance of other constructs. For example, in
286:
There are various types of inheritance, based on paradigm and specific language.
2403:
2128:
1669:
674:
670:
666:
618:
309:
944:
212:
another object (or objects of one class contain objects of another class); see
1761: – Using one interface or symbol with regards to multiple different types
1302:
to be substituted for another type or abstraction and is said to establish an
908:
some or all operations, replacing the base-class implementation with its own.
901:
229:
1737: – Reasoning that is rationally compelling, though not deductively valid
151:. The relationships of objects or classes through inheritance give rise to a
2477:
Designing an object-oriented programming language with behavioural subtyping
1501:
1299:
1295:
1289:
685:
661:
keyword in C#. Such modifiers are added to the class declaration before the
247:
181:
680:
A non-subclassable class has no subclasses, so it can be easily deduced at
317:
this to be the only case in which fashion affected the sequence of events."
2460:
1665:, combining properties of inheritance and composition into a new concept.
1776: – Programming paradigm based on conceptual understanding of objects
313:
1938:
1869:
1684:". The problem surfaces clearly in open object-oriented systems such as
654:
2485:
2000:
27:
Process of deriving classes from, and organizing them into, a hierarchy
1607:
superclass. (This kind of behavior, however, can be achieved with the
2123:. Lecture Notes in Computer Science. Vol. 2635. pp. 15–25.
856:
Inheritance is used to co-relate two or more classes to each other.
243:
1714:) allow program users to define variations of an entity at runtime.
1806:
399:
A derived class with multilevel inheritance is declared as follows:
251:
128:
2316:
1752:
869:
596:. Visibility specifies whether the features of the base class are
380:
base class because it provides a link for the inheritance between
336:
277:
269:
217:
220:
relationship, in contrast to the is-a relationship of subtyping.
1333:
is specified (via a reference, a pointer or the object itself).
1304:
927:. The base class comprises operations to compute the sum of the
185:
1782: – Set of methods that extend the functionality of a class
900:
Implementation inheritance is the mechanism whereby a subclass
669:, particularly when developers only have access to precompiled
2433:
Seiter, Linda M.; Palsberg, Jens; Lieberherr, Karl J. (1996).
1743: – Shared boundary between elements of a computing system
1496:
In programming languages that do not support inheritance as a
716:
are supported in the programming language that is being used.
29:
2317:"GotW #60: Exception-Safe Class Design, Part 2: Inheritance"
1547:
that contains the person's job-title, employer, and salary.
2341:. Tata McGraw Hill Education Private Limited. p. 609.
1919:
Cook, William R.; Hill, Walter; Canning, Peter S. (1990).
2118:"The Birth of Object Orientation: the Simula Languages"
1769:
Pages displaying short descriptions of redirect targets
1749: – Language feature in object-oriented programming
2435:"Evolution of object behavior using context relations"
2365:(2002). "10 "Concepts in object-oriented languages"".
1755: – Class in object-oriented programming languages
1903:
Advanced
Methods and Deep Learning in Computer Vision
1309:
an explicit inheritance relationship between classes
483:
This process can be extended to any number of levels.
2038:
Tempero, Ewan; Yang, Hong Yul; Noble, James (2013).
753:, then invocations of the superclass method will be
1591:The inheritance hierarchy of an object is fixed at
552:The general form of defining a derived class is:
246:67 programming language. The idea then spread to
529:entities from one or more other classes (called
120:
645:to the class declaration. Examples include the
302:
2096:Dahl, Ole-Johan; Nygaard, Kristen (May 1967).
637:In some languages a class may be declared as
8:
2041:What programmers do with inheritance in Java
1986:Mikhajlov, Leonid; Sekerinski, Emil (1998).
1294:Inheritance is similar to but distinct from
911:In the following Python example, subclasses
525:derivative classes that inherit one or more
123:) from existing ones such as super class or
1981:
1979:
1977:
2450:
2337:Venugopal, K.R.; Buyya, Rajkumar (2013).
1989:A study of the fragile base class problem
1928:
79:Learn how and when to remove this message
2398:
2396:
2394:
1970:. p. 32–33. SRC Research Report 45.
1914:
1912:
1603:object while retaining the state of its
771:
741:feature in Eiffel cannot be overridden.
180:Inheritance should not be confused with
119:. Also defined as deriving new classes (
1830:
1798:
1654:
2516:(1997). "24. Using Inheritance Well".
2439:ACM SIGSOFT Software Engineering Notes
2373:. Cambridge University Press. p.
2166:
2154:
2144:
2518:Object-Oriented Software Construction
1905:. Elsevier Science. pp. 179–342.
1788: – Technique in the C++ language
880:object-oriented programming languages
7:
2537:"Implementation Inheritance Is Evil"
2282:Object Oriented Programming With C++
1661:introduces a distinct relationship,
1321:is both a subclass and a subtype of
2085:(Technical report). pp. 15–16.
1838:Johnson, Ralph (August 26, 1991).
25:
2284:. Tata McGraw Hill. p. 213.
1488:// b can be substituted for an A.
874:Illustration of method overriding
2369:Concepts in programming language
943:
34:
2520:(2nd ed.). Prentice Hall.
2218:The Design and Evolution of C++
2099:Class and subclass declarations
1759:Polymorphism (computer science)
1726: – Software design pattern
950:Below is an example of Python.
765:Visibility of inherited members
204:Inheritance is contrasted with
158:An inherited class is called a
1767: – Abstraction of a class
1573:class that inherits from both
1527:For example, consider a class
704:), which requires one or more
405:// C++ language implementation
99:is the mechanism of basing an
1:
1968:Digital Equipment Corporation
1510:Liskov substitution principle
708:lookups depending on whether
2252:. Tata McGraw Hill. p.
2053:10.1007/978-3-642-39038-8_24
1921:Inheritance is not subtyping
1840:"Designing Reusable Classes"
1780:Trait (computer programming)
1678:"fragile base class problem"
1298:. Subtyping enables a given
749:If a superclass method is a
592:. The default visibility is
361:, which in turn serves as a
262:, and many other languages.
214:composition over inheritance
2558:Object-oriented programming
2129:10.1007/978-3-540-39993-3_3
502:Subclasses and superclasses
216:. Composition implements a
109:prototype-based inheritance
93:object-oriented programming
54:. The specific problem is:
18:Subclass (computer science)
2579:
2248:The complete reference C++
1691:Reportedly, Java inventor
1287:
1273:implementation inheritance
863:
195:implementation inheritance
50:to meet Knowledge (XXG)'s
1774:Role-oriented programming
1659:role-oriented programming
1636:composite reuse principle
923:method of the base class
778:Derived class visibility
777:
696:) can be used instead of
2535:Samokhin, Vadim (2017).
2474:America, Pierre (1991).
2220:. Pearson. p. 417.
2116:Dahl, Ole-Johan (2004).
2076:Hoare, C. A. R. (1966).
1335:
1284:Inheritance vs subtyping
952:
633:Non-subclassable classes
554:
486:Hierarchical inheritance
402:
1962:Cardelli, Luca (1993).
1712:Entity–component–system
1643:Issues and alternatives
1561:object can be either a
720:Non-overridable methods
113:class-based inheritance
2305:override(C# Reference)
1730:Circle–ellipse problem
1700:programming language.
1514:connotation/denotation
1325:and can be used as an
875:
775:Base class visibility
755:dynamically dispatched
342:
341:Multilevel inheritance
330:Multilevel inheritance
327:
283:
275:
153:directed acyclic graph
145:realizing an interface
2461:10.1145/250707.239108
2408:"Why extends is evil"
1901:Davies, Turk (2021).
1741:Interface (computing)
1288:Further information:
873:
788:Protected derivation
549:of its superclasses.
340:
304:"Multiple inheritance
281:
273:
191:interface inheritance
115:), retaining similar
107:upon another object (
1966:(Technical report).
1864:. pp. 397–406.
1735:Defeasible reasoning
1599:object to become an
1583:repeated inheritance
1506:behavioral subtyping
892:the inherited code.
710:multiple inheritance
706:virtual method table
296:Multiple inheritance
282:Multiple inheritance
137:overloaded operators
61:improve this article
2414:on 24 February 2019
1964:Typeful Programming
1939:10.1145/96709.96721
1870:10.1145/74877.74919
1786:Virtual inheritance
1676:in the form of the
1498:subtyping mechanism
1045:NotImplementedError
785:Private derivation
575:// subclass members
477:// C derived from B
450:// B derived from A
208:, where one object
2486:10.1007/BFb0019440
2214:Stroustrup, Bjarne
2001:10.1007/BFb0054099
1520:Design constraints
876:
791:Public derivation
737:method in C# or a
733:method in Java, a
714:single inheritance
641:by adding certain
543:instance variables
493:Hybrid inheritance
343:
290:Single inheritance
284:
276:
274:Single inheritance
206:object composition
2495:978-3-540-53931-5
2406:(1 August 2003).
2384:978-0-521-78098-8
2291:978-0-07-066907-9
2263:978-0-07-053246-5
2185:"C++ Inheritance"
2165:Missing or empty
2138:978-3-540-21366-6
2062:978-3-642-39038-8
2010:978-3-540-64737-9
1747:Method overriding
1724:Archetype pattern
1609:decorator pattern
1162:SquareSumComputer
913:SquareSumComputer
866:Method overriding
849:
848:
598:privately derived
323:Bjarne Stroustrup
89:
88:
81:
52:quality standards
43:This article may
16:(Redirected from
2570:
2544:
2531:
2500:
2499:
2471:
2465:
2464:
2454:
2430:
2424:
2423:
2421:
2419:
2410:. Archived from
2400:
2389:
2388:
2372:
2359:
2353:
2352:
2334:
2328:
2327:
2325:
2324:
2313:
2307:
2302:
2296:
2295:
2278:Balagurusamy, E.
2274:
2268:
2267:
2251:
2242:Schildt, Herbert
2238:
2232:
2231:
2210:
2204:
2203:
2201:
2200:
2191:. Archived from
2181:
2175:
2174:
2168:
2162:
2156:
2152:
2150:
2142:
2122:
2113:
2107:
2106:
2104:
2093:
2087:
2086:
2084:
2073:
2067:
2066:
2046:
2035:
2029:
2028:
2026:
2025:
2019:
2013:. Archived from
1994:
1983:
1972:
1971:
1959:
1953:
1952:
1932:
1916:
1907:
1906:
1898:
1892:
1891:
1857:
1851:
1850:
1844:
1835:
1818:
1803:
1770:
1628:
1624:
1606:
1602:
1598:
1580:
1576:
1572:
1568:
1564:
1560:
1546:
1542:
1538:
1534:
1530:
1492:
1489:
1486:
1483:
1480:
1477:
1474:
1471:
1468:
1465:
1462:
1459:
1456:
1453:
1450:
1447:
1446:DoSomethingALike
1444:
1441:
1438:
1435:
1432:
1429:
1426:
1423:
1420:
1417:
1414:
1411:
1408:
1405:
1402:
1399:
1398:DoSomethingBLike
1396:
1393:
1390:
1387:
1384:
1381:
1378:
1375:
1372:
1369:
1366:
1363:
1360:
1357:
1356:DoSomethingALike
1354:
1351:
1348:
1345:
1342:
1339:
1259:
1256:
1253:
1250:
1247:
1244:
1241:
1238:
1235:
1232:
1229:
1226:
1223:
1220:
1217:
1214:
1211:
1208:
1205:
1202:
1199:
1196:
1193:
1190:
1187:
1184:
1181:
1178:
1175:
1172:
1169:
1166:
1163:
1160:
1157:
1154:
1151:
1148:
1145:
1142:
1139:
1136:
1133:
1130:
1127:
1124:
1121:
1118:
1115:
1112:
1109:
1106:
1103:
1100:
1097:
1094:
1091:
1088:
1085:
1082:
1079:
1076:
1073:
1070:
1067:
1064:
1061:
1058:
1055:
1052:
1049:
1046:
1043:
1040:
1037:
1034:
1031:
1028:
1025:
1022:
1019:
1016:
1013:
1010:
1007:
1004:
1001:
998:
995:
992:
989:
986:
983:
980:
977:
974:
971:
968:
965:
962:
959:
956:
947:
926:
922:
918:
914:
772:
759:inline expansion
740:
736:
732:
702:dynamic dispatch
664:
660:
648:
639:non-subclassable
627:method signature
602:publicly derived
579:
576:
573:
570:
567:
564:
561:
558:
547:member functions
478:
475:
472:
469:
466:
463:
460:
457:
454:
451:
448:
445:
442:
439:
436:
433:
430:
427:
424:
421:
418:
415:
412:
409:
406:
394:inheritance path
325:
307:
199:code inheritance
141:friend functions
84:
77:
73:
70:
64:
38:
37:
30:
21:
2578:
2577:
2573:
2572:
2571:
2569:
2568:
2567:
2548:
2547:
2534:
2528:
2514:Meyer, Bertrand
2512:
2509:
2507:Further reading
2504:
2503:
2496:
2473:
2472:
2468:
2432:
2431:
2427:
2417:
2415:
2402:
2401:
2392:
2385:
2361:
2360:
2356:
2349:
2336:
2335:
2331:
2322:
2320:
2315:
2314:
2310:
2303:
2299:
2292:
2276:
2275:
2271:
2264:
2240:
2239:
2235:
2228:
2212:
2211:
2207:
2198:
2196:
2189:www.cs.nmsu.edu
2183:
2182:
2178:
2164:
2153:
2143:
2139:
2120:
2115:
2114:
2110:
2102:
2095:
2094:
2090:
2082:
2079:Record Handling
2075:
2074:
2070:
2063:
2044:
2037:
2036:
2032:
2023:
2021:
2017:
2011:
1992:
1985:
1984:
1975:
1961:
1960:
1956:
1949:
1930:10.1.1.102.8635
1918:
1917:
1910:
1900:
1899:
1895:
1880:
1859:
1858:
1854:
1847:www.cse.msu.edu
1842:
1837:
1836:
1832:
1827:
1822:
1821:
1804:
1800:
1795:
1768:
1720:
1650:Design Patterns
1645:
1626:
1622:
1604:
1600:
1596:
1578:
1574:
1571:StudentEmployee
1570:
1566:
1562:
1558:
1544:
1540:
1536:
1532:
1528:
1522:
1494:
1493:
1490:
1487:
1484:
1481:
1478:
1475:
1472:
1469:
1466:
1463:
1460:
1457:
1454:
1451:
1448:
1445:
1442:
1439:
1436:
1433:
1430:
1427:
1424:
1421:
1418:
1415:
1412:
1409:
1406:
1403:
1400:
1397:
1394:
1391:
1388:
1385:
1382:
1379:
1376:
1373:
1370:
1367:
1364:
1361:
1358:
1355:
1352:
1349:
1346:
1343:
1340:
1337:
1292:
1286:
1261:
1260:
1257:
1254:
1251:
1248:
1245:
1242:
1239:
1236:
1233:
1230:
1227:
1224:
1221:
1218:
1215:
1212:
1210:CubeSumComputer
1209:
1206:
1203:
1200:
1197:
1194:
1191:
1188:
1185:
1182:
1179:
1176:
1173:
1170:
1167:
1164:
1161:
1158:
1155:
1152:
1149:
1146:
1143:
1140:
1137:
1134:
1131:
1128:
1125:
1122:
1119:
1116:
1113:
1110:
1107:
1104:
1101:
1098:
1095:
1092:
1089:
1086:
1083:
1080:
1077:
1074:
1071:
1068:
1065:
1062:
1059:
1056:
1053:
1050:
1047:
1044:
1041:
1038:
1035:
1032:
1029:
1026:
1023:
1020:
1017:
1014:
1011:
1008:
1005:
1002:
999:
996:
993:
990:
987:
984:
981:
978:
975:
972:
969:
966:
963:
960:
957:
954:
924:
920:
917:CubeSumComputer
916:
912:
898:
868:
862:
854:
767:
747:
745:Virtual methods
738:
734:
730:
722:
694:static dispatch
662:
658:
657:onwards or the
646:
643:class modifiers
635:
581:
580:
577:
574:
571:
568:
565:
562:
559:
556:
511:derived classes
504:
480:
479:
476:
473:
470:
467:
464:
461:
458:
455:
452:
449:
446:
443:
440:
437:
434:
431:
428:
425:
422:
419:
416:
413:
410:
407:
404:
326:
321:
305:
268:
239:Kristen Nygaard
226:
135:, destructors,
85:
74:
68:
65:
58:
39:
35:
28:
23:
22:
15:
12:
11:
5:
2576:
2574:
2566:
2565:
2560:
2550:
2549:
2546:
2545:
2532:
2526:
2508:
2505:
2502:
2501:
2494:
2466:
2452:10.1.1.36.5053
2425:
2390:
2383:
2363:Mitchell, John
2354:
2347:
2329:
2308:
2297:
2290:
2269:
2262:
2233:
2226:
2205:
2176:
2155:|journal=
2137:
2108:
2088:
2068:
2061:
2030:
2009:
1973:
1954:
1947:
1908:
1893:
1878:
1852:
1829:
1828:
1826:
1823:
1820:
1819:
1797:
1796:
1794:
1791:
1790:
1789:
1783:
1777:
1771:
1762:
1756:
1750:
1744:
1738:
1732:
1727:
1719:
1716:
1644:
1641:
1632:
1631:
1615:
1612:
1589:
1586:
1555:
1521:
1518:
1336:
1285:
1282:
953:
897:
894:
864:Main article:
861:
858:
853:
850:
847:
846:
845:
844:
841:
838:
833:
832:
831:
828:
825:
820:
819:
818:
815:
812:
807:
806:
805:
802:
799:
793:
792:
789:
786:
783:
780:
779:
776:
766:
763:
751:virtual method
746:
743:
721:
718:
634:
631:
606:
605:
555:
539:parent classes
503:
500:
499:
498:
494:
491:
487:
484:
481:
403:
400:
397:
344:
334:
331:
328:
319:
300:
297:
294:
291:
267:
264:
235:Ole-Johan Dahl
225:
222:
117:implementation
87:
86:
42:
40:
33:
26:
24:
14:
13:
10:
9:
6:
4:
3:
2:
2575:
2564:
2561:
2559:
2556:
2555:
2553:
2542:
2538:
2533:
2529:
2527:0-13-629155-4
2523:
2519:
2515:
2511:
2510:
2506:
2497:
2491:
2487:
2483:
2479:
2478:
2470:
2467:
2462:
2458:
2453:
2448:
2444:
2440:
2436:
2429:
2426:
2413:
2409:
2405:
2399:
2397:
2395:
2391:
2386:
2380:
2376:
2371:
2370:
2364:
2358:
2355:
2350:
2348:9781259029943
2344:
2340:
2339:Mastering C++
2333:
2330:
2318:
2312:
2309:
2306:
2301:
2298:
2293:
2287:
2283:
2279:
2273:
2270:
2265:
2259:
2255:
2250:
2249:
2243:
2237:
2234:
2229:
2227:9780135229477
2223:
2219:
2215:
2209:
2206:
2195:on 2023-09-24
2194:
2190:
2186:
2180:
2177:
2172:
2160:
2148:
2140:
2134:
2130:
2126:
2119:
2112:
2109:
2101:
2100:
2092:
2089:
2081:
2080:
2072:
2069:
2064:
2058:
2054:
2050:
2043:
2042:
2034:
2031:
2020:on 2017-08-13
2016:
2012:
2006:
2002:
1998:
1991:
1990:
1982:
1980:
1978:
1974:
1969:
1965:
1958:
1955:
1950:
1948:0-89791-343-4
1944:
1940:
1936:
1931:
1926:
1922:
1915:
1913:
1909:
1904:
1897:
1894:
1889:
1885:
1881:
1875:
1871:
1867:
1863:
1856:
1853:
1848:
1841:
1834:
1831:
1824:
1816:
1812:
1808:
1802:
1799:
1792:
1787:
1784:
1781:
1778:
1775:
1772:
1766:
1763:
1760:
1757:
1754:
1751:
1748:
1745:
1742:
1739:
1736:
1733:
1731:
1728:
1725:
1722:
1721:
1717:
1715:
1713:
1708:
1706:
1705:yo-yo problem
1701:
1699:
1694:
1693:James Gosling
1689:
1687:
1683:
1682:encapsulation
1679:
1675:
1671:
1668:According to
1666:
1664:
1660:
1656:
1652:
1651:
1642:
1640:
1637:
1620:
1616:
1613:
1610:
1594:
1593:instantiation
1590:
1587:
1584:
1556:
1553:
1552:
1551:
1548:
1525:
1519:
1517:
1515:
1511:
1507:
1503:
1499:
1334:
1332:
1328:
1324:
1320:
1316:
1312:
1307:
1306:
1301:
1297:
1291:
1283:
1281:
1277:
1274:
1270:
1266:
951:
948:
946:
941:
939:
935:
930:
919:override the
909:
907:
903:
895:
893:
891:
887:
886:
881:
872:
867:
859:
857:
851:
842:
839:
837:Not inherited
836:
835:
834:
829:
826:
824:Not inherited
823:
822:
821:
816:
813:
811:Not inherited
810:
809:
808:
803:
800:
797:
796:
795:
794:
790:
787:
784:
782:
781:
774:
773:
770:
764:
762:
760:
756:
752:
744:
742:
728:
719:
717:
715:
711:
707:
703:
700:(also called
699:
695:
692:(also called
691:
690:early binding
687:
683:
678:
676:
672:
668:
656:
652:
644:
640:
632:
630:
628:
624:
620:
615:
611:
603:
599:
595:
591:
587:
583:
582:
553:
550:
548:
544:
540:
536:
532:
528:
524:
520:
519:child classes
516:
512:
508:
501:
495:
492:
488:
485:
482:
423:// Base class
401:
398:
395:
391:
387:
383:
379:
375:
371:
368:
367:derived class
364:
360:
357:
356:derived class
353:
349:
345:
339:
335:
332:
329:
324:
318:
315:
311:
301:
298:
295:
292:
289:
288:
287:
280:
272:
265:
263:
261:
257:
253:
249:
245:
240:
236:
231:
223:
221:
219:
215:
211:
207:
202:
200:
196:
192:
187:
183:
178:
176:
172:
171:
166:
165:inherits from
161:
156:
154:
150:
146:
142:
138:
134:
130:
126:
122:
118:
114:
110:
106:
102:
98:
94:
83:
80:
72:
62:
57:
53:
49:
48:
41:
32:
31:
19:
2563:Type systems
2540:
2517:
2476:
2469:
2442:
2438:
2428:
2416:. Retrieved
2412:the original
2404:Holub, Allen
2368:
2357:
2338:
2332:
2321:. Retrieved
2311:
2300:
2281:
2272:
2247:
2236:
2217:
2208:
2197:. Retrieved
2193:the original
2188:
2179:
2167:|title=
2111:
2098:
2091:
2078:
2071:
2040:
2033:
2022:. Retrieved
2015:the original
1988:
1963:
1957:
1920:
1902:
1896:
1861:
1855:
1846:
1833:
1813:, Java, and
1801:
1709:
1702:
1690:
1667:
1662:
1648:
1646:
1633:
1549:
1526:
1523:
1495:
1330:
1326:
1322:
1318:
1314:
1310:
1303:
1293:
1278:
1272:
1262:
949:
942:
910:
899:
883:
877:
855:
852:Applications
768:
748:
723:
698:late binding
682:compile time
679:
636:
623:compile-time
607:
601:
597:
593:
589:
585:
551:
538:
535:base classes
534:
530:
518:
515:heir classes
514:
510:
506:
505:
497:inheritance.
393:
392:is known as
389:
388:. The chain
385:
381:
378:intermediate
377:
376:is known as
373:
372:. The class
369:
366:
362:
358:
355:
351:
350:serves as a
347:
303:
285:
227:
209:
203:
198:
194:
190:
179:
175:delegates to
174:
173:(one object
168:
164:
159:
157:
133:constructors
111:) or class (
96:
90:
75:
66:
59:Please help
55:
44:
1670:Allen Holub
1512:. (Compare
1329:wherever a
1265:polymorphic
1216:SumComputer
1168:SumComputer
958:SumComputer
925:SumComputer
921:transform()
801:Protected →
675:source code
667:reusability
649:keyword in
490:subclasses.
310:Objective C
121:sub classes
97:inheritance
63:if you can.
2552:Categories
2541:HackerNoon
2323:2012-08-15
2199:2018-05-16
2024:2015-08-28
1879:0897913337
1825:References
1686:frameworks
1614:Visibility
1554:Singleness
1269:delegation
896:Code reuse
885:overriding
860:Overriding
569:SuperClass
566:visibility
531:superclass
507:Subclasses
363:base class
352:base class
346:The class
230:Tony Hoare
170:delegation
149:interfaces
125:base class
69:April 2015
56:Cluttered.
2543:. Medium.
2447:CiteSeerX
2445:(6): 46.
2319:. Gotw.ca
2157:ignored (
2147:cite book
1925:CiteSeerX
1663:played-by
1296:subtyping
1290:Subtyping
1225:transform
1177:transform
1126:transform
1024:transform
840:Protected
830:Protected
827:Protected
798:Private →
686:upcasting
614:contracts
248:Smalltalk
228:In 1966,
182:subtyping
2418:10 March
2280:(2010).
2244:(2003).
2216:(1994).
1765:Protocol
1718:See also
1674:coupling
1601:Employee
1579:Employee
1567:Employee
1545:Employee
1458:SomeFunc
1317:, where
967:__init__
906:override
804:Public →
712:or only
673:and not
671:binaries
560:SubClass
527:language
365:for the
354:for the
320:—
314:Brad Cox
210:contains
160:subclass
45:require
1888:1104130
1623:Student
1597:Student
1575:Student
1563:Student
1543:called
1537:Student
1535:called
1099:compute
929:squares
902:re-uses
817:Private
814:Private
727:private
594:private
586:private
523:modular
224:History
47:cleanup
2524:
2492:
2449:
2381:
2345:
2288:
2260:
2224:
2135:
2059:
2007:
1945:
1927:
1886:
1876:
1627:Person
1605:Person
1588:Static
1565:or an
1559:Person
1541:Person
1533:Person
1529:Person
1476:UseAnA
1416:UseAnA
1389:public
1380:public
1347:public
1243:return
1195:return
1153:inputs
1111:return
1063:return
1051:inputs
934:square
890:hiding
843:Public
739:frozen
735:sealed
659:sealed
619:reused
610:Eiffel
590:public
462:public
435:public
306:
260:Python
244:Simula
101:object
2121:(PDF)
2103:(PDF)
2083:(PDF)
2045:(PDF)
2018:(PDF)
1993:(PDF)
1884:S2CID
1843:(PDF)
1815:Scala
1793:Notes
1753:Mixin
1655:above
1502:types
1428:&
1422:const
1404:const
1371:class
1362:const
1338:class
1207:class
1159:class
1141:value
1132:value
1066:range
1042:raise
955:class
878:Many
731:final
663:class
655:C++11
647:final
557:class
537:, or
517:, or
453:class
426:class
408:class
266:Types
218:has-a
105:class
2522:ISBN
2490:ISBN
2420:2015
2379:ISBN
2343:ISBN
2286:ISBN
2258:ISBN
2222:ISBN
2171:help
2159:help
2133:ISBN
2057:ISBN
2005:ISBN
1943:ISBN
1874:ISBN
1634:The
1619:cast
1577:and
1455:void
1413:void
1395:void
1353:void
1313:and
1305:is-a
1300:type
1231:self
1183:self
1147:self
1120:self
1105:self
1084:self
1072:self
1057:self
1030:self
1006:self
991:self
973:self
938:cube
936:and
915:and
653:and
651:Java
545:and
521:are
384:and
256:Java
237:and
186:is-a
139:and
2482:doi
2457:doi
2375:287
2254:417
2125:doi
2049:doi
1997:doi
1935:doi
1866:doi
1807:C++
1630:it.
1449:();
1222:def
1174:def
1156:())
1138:for
1114:sum
1096:def
1048:def
1021:def
964:def
600:or
588:or
471:...
444:...
417:...
390:ABC
252:C++
197:or
129:C++
103:or
91:In
2554::
2539:.
2488:.
2455:.
2443:21
2441:.
2437:.
2393:^
2377:.
2256:.
2187:.
2163:;
2151::
2149:}}
2145:{{
2131:.
2055:.
2003:.
1976:^
1941:.
1933:.
1911:^
1882:.
1872:.
1845:.
1811:C#
1809:,
1698:Go
1485:);
1461:()
1410:};
1407:{}
1401:()
1368:};
1365:{}
1359:()
1240:):
1219:):
1192:):
1171:):
1144:in
1108:):
1060:):
1039:):
988:):
761:.
677:.
629:.
612:,
578:};
533:,
513:,
509:,
474:};
447:};
420:};
312:,
258:,
254:,
250:,
155:.
95:,
2530:.
2498:.
2484::
2463:.
2459::
2422:.
2387:.
2351:.
2326:.
2294:.
2266:.
2230:.
2202:.
2173:)
2169:(
2161:)
2141:.
2127::
2065:.
2051::
2027:.
1999::
1951:.
1937::
1890:.
1868::
1849:.
1817:.
1585:.
1491:}
1482:b
1479:(
1473:;
1470:b
1467:B
1464:{
1452:}
1443:.
1440:a
1437:{
1434:)
1431:a
1425:A
1419:(
1392::
1386:{
1383:A
1377::
1374:B
1350::
1344:{
1341:A
1331:B
1327:A
1323:A
1319:B
1315:A
1311:B
1258:x
1255:*
1252:x
1249:*
1246:x
1237:x
1234:,
1228:(
1213:(
1204:x
1201:*
1198:x
1189:x
1186:,
1180:(
1165:(
1150:.
1135:)
1129:(
1123:.
1117:(
1102:(
1093:)
1090:b
1087:.
1081:,
1078:a
1075:.
1069:(
1054:(
1036:x
1033:,
1027:(
1018:b
1015:=
1012:b
1009:.
1003:a
1000:=
997:a
994:.
985:b
982:,
979:a
976:,
970:(
961::
604:.
572:{
563::
468:{
465:B
459::
456:C
441:{
438:A
432::
429:B
414:{
411:A
396:.
386:C
382:A
374:B
370:C
359:B
348:A
82:)
76:(
71:)
67:(
20:)
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.