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Pattern · Core

Factory Method

Define a method for creating an object, but let SUBCLASSES decide which concrete class to instantiate — so the creator code never names a product directly.

Asked atAmazonMicrosoftUber
step 1 / 11
1/2Hard-wired new
Dialog
+ render()
Hard-wired new
 1class Dialog {
 2    void render() {
 3        Button b = new WindowsButton();   // hard-coded concrete
 4        b.onClick();
 5    }
 6}
State
createsnew WindowsButton() 💥
✦

Dialog.render() does `new WindowsButton()` directly — the layout class names a concrete widget.