工厂方法模式

• 

  • /**
    *
    */
    public abstract class OperationBean {
        private double _numberA = 0;//字段，即属性
        private double _numberB = 0;
    
    
    
        public double get_numberB() {
            return _numberB;
        }
    
        public void set_numberB(double _numberB) {
            this._numberB = _numberB;
        }
    
        public double get_numberA() {
            return _numberA;
        }
    
        public void set_numberA(double _numberA) {
            this._numberA = _numberA;
        }
        public  abstract  double GetResult();
    }
    
    
    public class OperationAdd extends OperationBean {
        @Override
        public double GetResult() {
            double result = 0;
            result = get_numberA() + get_numberB();
            return result;
        }
    }
    
    
    /**
     * 
     */
    public class OperationSub extends OperationBean {
        @Override
        public double GetResult() {
            double result = 0;
            result = get_numberA() - get_numberB();
            return result;
        }
    }
    
    
    /**
     * 
     */
    public class OperationMul extends OperationBean {
        @Override
        public double GetResult() {
            double result = 0;
            result = get_numberA() * get_numberB();
            return result;
        }
    }
    
    
    /**
     * 
     */
    public class OperationDiv extends OperationBean {
        @Override
        public double GetResult() {
            double result = 0;
            result = get_numberA() / get_numberB();
            return result;
        }
    }
    
    /**
     * 工厂类
     */
    public class OperationFactory{
    
        public static OperationBean createOperation(String operate){
            OperationBean operation = null;
            switch (operate){
                case "+":
                    operation =  new OperationAdd();
                    break;
                case "-":
                    operation =  new OperationSub();
                    break;
                case "*":
                    operation =  new OperationMul();
                    break;
                case "/":
                    operation =  new OperationSub();
                    break;
            }
            return operation;
        }
    
    
    }
    
    
    
    /**
     * 客户端代码
     */
    public class TestUtil {
    
        public static void main(String[] args) {
            
            OperationBean operation = OperationFactory.createOperation("+");
            operation.set_numberA(1);
            operation.set_numberB(2);
            System.out.println(operation.GetResult()+"");;
    
        }
    }

• 工厂方法模式定义一个用于创建对象的接口，让子类决定实例化哪一个类。工厂方法使一个类的实例话延迟到了其子类。
  • 

  • /**
     * 工厂类
     */
    public abstract class BossOperationFactory {
    
        public abstract OperationBean createOperation();
    }
    
    
    /**
     * 加法工厂
     */
    public class AddFactory extends BossOperationFactory {
        @Override
        public OperationBean createOperation() {
            return new OperationAdd();
        }
    }
    
    /**
     * 减法工厂
     */
    public class SubFactory extends BossOperationFactory {
        @Override
        public OperationBean createOperation() {
            return new OperationSub();
        }
    }
    
    /**
     * 乘法工厂
     */
    public class MulFactory extends BossOperationFactory {
        @Override
        public OperationBean createOperation() {
            return new OperationMul();
        }
    }
    
    
    /**
     * 除法工厂
     */
    public class DivFactory extends BossOperationFactory {
        @Override
        public OperationBean createOperation() {
            return new OperationDiv();
        }
    }
    
    
    /**
     * 客户端代码
     */
    public class TestUtil {
    
        public static void main(String[] args) {
         
            BossOperationFactory factory = new AddFactory();
            OperationBean operationBean = factory.createOperation();
            operationBean.set_numberA(1);
            operationBean.set_numberB(2);
            System.out.println(operationBean.GetResult()+"");
    
        }
    }

• 抽象工厂模式（Abstract Factory）
  • 提供一个创建一系列相关或互相依赖对象的接口，而无需指定它们具体的类。
  • 利用反射，通过配置文件设置参数和获取配置文件参数。