一（2）工厂模式

1 简单工厂模式的缺陷？

　　简单工厂模式的工厂加入逻辑判断逻辑，当要增加新的具体工厂时，需要修改代码。这违背了“开放-封边”原则。

2 工厂模式？

　　工厂模式为每一个具体类都设计一个工厂，这样可以改掉简单工厂的弊端。

3 工厂模式的缺陷？

　　每增加一个产品就需要增加一个产品的工厂类，增加了额外的开发量

package com.biao.factory.factory;


public class FactoryDemo {
    public static void main(String[] args) {
        OperationFactory factory = new addOperationFactory();
        Operation addOperation = factory.createOperation();//非静态方法由对象直接调用。
        addOperation.numberA = 3;
        addOperation.numberB = 3;
        System.out.println(addOperation.getResult());;
    }
}

/*
静态方法直接类名调用
非静态方法先创建对象，然后通过对象调用。
*/

abstract class Operation{
    public double numberA;
    public double numberB;
    abstract double getResult();
}
class OperationAdd extends Operation{
    @Override
    double getResult() {
        return numberA+numberB;
    }
    
}
class OperationSub extends Operation{
    @Override
    double getResult() {
        return numberA-numberB;
    }
    
}
class OperationMul extends Operation{
    @Override
    double getResult() {
        return numberA*numberB;
    }
    
}
class OperationDiv extends Operation{
    @Override
    double getResult() {
        return numberA/numberB;
    }
    
}

interface OperationFactory{
    Operation createOperation();
}

class addOperationFactory implements OperationFactory{

    @Override
    public Operation createOperation() {
        // TODO Auto-generated method stub
        return new OperationAdd();
    }
    
}
class subOperationFactory implements OperationFactory{
    
    @Override
    public Operation createOperation() {
        // TODO Auto-generated method stub
        return new OperationSub();
    }
    
}
class mulOperationFactory implements OperationFactory{
    
    @Override
    public Operation createOperation() {
        // TODO Auto-generated method stub
        return new OperationMul();
    }
    
}
class divOperationFactory implements OperationFactory{
    
    @Override
    public Operation createOperation() {
        // TODO Auto-generated method stub
        return new OperationDiv();
    }
    
}