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Why are there state patterns?
The state pattern is used in computer programming to encapsulate varying behavior for the same object, based on its internal state. This can be a cleaner way for an object to change its behavior at runtime without resorting to conditional statements and thus improve maintainability.
Does Strategy pattern use inheritance?
Strategy is a pattern of OOP and Inheritance is a principle of OOP. Strategy is implemented using (or to support) Inheritance (actually, interface generalization). Strategy assumes to have different implementations which can be replaced in runtime (or configured in a flexible way).
What is resolver pattern?
A key part of the ShortURL resolvers is an algorithm to map the path info URLs to fully qualified class names (and vice versa). The algorithm uses two regular expressions 1) a class pattern regex used to extract the sname from a class name, and 2) a URL pattern regex used to extract the sname from a URL.
When to use pattern inheritance over directed inheritance?
Pattern Inheritance is given preference above Directed Inheritance. As per Pega, if PRPC needs to find RULES (reusable components) which a particular class can use or have access to, first they search through the pattern inheritance.
What are the problems with multiple inheritance of State?
Because interfaces do not contain fields, you do not have to worry about problems that result from multiple inheritance of state. Multiple inheritance of implementation is the ability to inherit method definitions from multiple classes. Problems arise with this type of multiple inheritance, such as name conflicts and ambiguity.
When to use pattern inheritance or directed inheritance in Pega?
As per Pega, if PRPC needs to find RULES (reusable components) which a particular class can use or have access to, first they search through the pattern inheritance. Which is nothing but, the naming convention followed to name a particular RULE in Pega.
Can a class inherit different implementations of a method?
As with multiple inheritance of implementation, a class can inherit different implementations of a method defined (as default or static) in the interfaces that it extends. In this case, the compiler or the user must decide which one to use.