面向对象系统分析与设计单例模式.pptVIP

Neusoft Computer Science and Technology Department copy right Neusoft Computer Science and Technology Department copy right * Neusoft Computer Science and Technology Department copy right * OO System Analysis Design 【Singleton Pattern】 * Neusoft Computer Science and Technology Department copy right * Enjoy chocolate… * Neusoft Computer Science and Technology Department copy right * Our job is: To design a chocolate boiler, which could make a chocolate bars. * Neusoft Computer Science and Technology Department copy right * The rules of chocolate boiler: To fill the boiler it must be empty; To drain the boiler it must be full and also boiled. To boil the boiler it must be full and not already boiled. * Neusoft Computer Science and Technology Department copy right * How to design the class? properties? method body? * Neusoft Computer Science and Technology Department copy right * A class diagram: * Neusoft Computer Science and Technology Department copy right * Question: Can you improve the ChocolateBoiler class into which only one instance of ChocalateBoiler is created in an application? * Neusoft Computer Science and Technology Department copy right * The Singleton Pattern The Singleton Pattern ensures a class has only one instance, and provides a global point of access to it. * Neusoft Computer Science and Technology Department copy right * Class diagram: Factory Method Holds our one and only instance of Singleton. You can conveniently access the method anywhere? * Neusoft Computer Science and Technology Department copy right * Class is over Congratulations! Neusoft Computer Science and Technology Department copy right Neusoft Computer Science and Technology Department copy right