java - Confusion in Builder plus Singleton pattern in example from fluffycat -


i tryingout builder examples fluffycat

sodaimpsingleton sodaimpsingleton = new sodaimpsingleton(new cherrysodaimp()); system.out.println("testing medium soda on cherry platform"); mediumsoda mediumsoda = new mediumsoda(); mediumsoda.poursoda();

here there no relation between sodaimsingleton , mediumsuda, still when mediumsoda.poursoda() called prints cherrysodaimp.poursodaimp() how/why happening?

there relationship. sodaimpsingleton instantiated cherrysodaimp. next, mediumsoda extends soda , in constructor calling method setsodaimp(), implemented sodaimpsingleton.getthesodaimp(); in abstract soda class, static method returns cherrysodaimp instance created on first line.


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