package com.csdhsm.designpattem.simplefactory;/**  * <p>All rights Reserved, Designed By Han</p>* @Title:  Operator.java   * @Package com.csdhsm.designpattem.simplefactory   * @Description: 运算抽象类，提供抽象方法* @author: Han   * @E-mail: 294098789@qq.com  * @date:   2016年6月16日 上午10:48:44   * @version:V1.0     */
public abstract class Operator {protected double num1 = 0;protected double num2 = 0;public void setNum1(double num1) {this.num1 = num1;}public void setNum2(double num2) {this.num2 = num2;}//抽象方法abstract public double calculate();
}

package com.csdhsm.designpattem.simplefactory;/**  * <p>All rights Reserved, Designed By Han</p>* <p>For Taoyuan Web Application</p>* @Title:  FourOperations.java   * @Package com.csdhsm.designpattem.simplefactory   * @Description: TODO * @author: Han   * @E-mail: 294098789@qq.com  * @date:   2016年6月16日 上午10:50:09   * @version:V1.0     */
class OperationAdd extends Operator {@Overridepublic double calculate() {return num1 + num2;}
}class OperationSub extends Operator {@Overridepublic double calculate() {return num1 - num2;}
}class OperationMul extends Operator {@Overridepublic double calculate() {return num1 * num2;}
}class OperationDiv extends Operator {@Overridepublic double calculate() {if(num2 == 0)throw new RuntimeException("除数不能为0!");return num1 / num2;}
}

package com.csdhsm.designpattem.simplefactory;/*** <p> All rights Reserved, Designed By Han</p>* @Title: Factory.java* @Package com.csdhsm.designpattem.simplefactory* @Description: 工厂类* @author: Han* @E-mail: 294098789@qq.com* @date: 2016年6月16日 上午10:33:48* @version:V1.0*/
public class Factory {private static Operator operator;public static Operator getOperator(String type) {if (type == null) {throw new NullPointerException();}//根据运算符号获得对应的计算类(对字符串switch/case判断，只有jdk1.7以上版本)switch (type) {case "+":operator = new OperationAdd();break;case "-":operator = new OperationSub();break;case "*":operator = new OperationMul();break;case "/":operator = new OperationDiv();break;default:throw new RuntimeException("未能识别的符号!");}return operator;}
}

package com.csdhsm.designpattem.simplefactory;/**  * <p>All rights Reserved, Designed By Han</p>* @Title:  Solution.java   * @Package com.csdhsm.designpattem.simplefactory   * @Description: 简单工厂模式* @author: Han   * @E-mail: 294098789@qq.com  * @date:   2016年6月7日 下午3:44:07   * @version:V1.0     */
public class Solution {public static void main(String[] args) {double num1 = 7;double num2 = 0;String type = "*";Operator operator = Factory.getOperator(type);operator.setNum1(num1);operator.setNum2(num2);System.out.println(operator.calculate());}
}