??? 簡單工廠模式最大的優(yōu)點(diǎn)在于工廠類中包含了必要的邏輯判斷。

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    // 產(chǎn)品接口---水果接口
public interface Fruit {
	public void plant();
}

// 產(chǎn)品----蘋果類
public class Apple implements Fruit {
	public void plant() {
		System.out.println("plant apple!");
	}
}

// 產(chǎn)品----草莓類
public class Strawberry implements Fruit {
	public void plant() {
		System.out.println("plant Strawberry!");
	}
}

// 工廠異常類
public class BadFruitException extends Exception {
	public BadFruitException(String msg) {
		super(msg); // 調(diào)用父類的構(gòu)造方法
	}
}

// 工廠----園丁類
public class FruitGardener {// 靜態(tài)工廠方法
	public static Fruit factory(String which) throws BadFruitException {
		if (which.equalsIgnoreCase("apple")) {
			return new Apple();
		} else if (which.equalsIgnoreCase("strawberry")) {
			return new Strawberry();
		} else {
			throw new BadFruitException("Bad fruit request");
		}
	}
}

// 測試類
public class TestApp {
	private void test(String fruitName) {
		try {
			Fruit f = FruitGardener.factory(fruitName);
			System.out.println("恭喜!生產(chǎn)了一個(gè)水果對象:" + fruitName);
		} catch (BadFruitException e) {
			System.out.println("工廠目前不能生產(chǎn)產(chǎn)品:" + fruitName);
			System.out.println(e.getMessage());// 輸出異常信息
		}
	}

	public static void main(String args[]) {
		TestApp t = new TestApp();
		t.test("apple");
		t.test("strawberry");
		t.test("car"); // 此處會(huì)拋異常,水果工廠能生產(chǎn)car(轎車)嗎!
	}
}
  

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創(chuàng)建型設(shè)計(jì)模式--簡單工廠