大话设计模式1 简单工厂模式 的java代码实现

首先是Operation抽象类：

package yx.designpattern.simpleFactory;abstract class Operation {public double number1;public double number2;public double getNumber1() {return number1;}public void setNumber1(double number1) {this.number1 = number1;}public double getNumber2() {return number2;}public void setNumber2(double number2) {this.number2 = number2;}public abstract double getResult() throws Exception;}

继承Operation的加法类：OperationAdd

package yx.designpattern.simpleFactory;public class OperationAdd extends Operation {@Overridepublic double getResult() {return number1+number2;}}

继承Operation的减法类：OperationSub

package yx.designpattern.simpleFactory;public class OperationSub extends Operation {@Overridepublic double getResult() {return number1-number2;}}

继承Operation的乘法类：OperationMul

package yx.designpattern.simpleFactory;public class OperationMul extends Operation {@Overridepublic double getResult() {return number1*number2;}}

继承Operation的除法类：OperationDiv:

package yx.designpattern.simpleFactory;public class OperationDiv extends Operation {@Overridepublic double getResult() throws Exception {if(number2==0){throw new Exception("除数不能为0");}return number1/number2;}}

生成Operation的工厂类：OperationFactory

package yx.designpattern.simpleFactory;public class OperationFactory {public static Operation createOperation(char operation){Operation oper=null;switch(operation){case '+' :oper=new OperationAdd();break;case '-':oper=new OperationSub();break;case '*':oper=new OperationMul();break;case '/':oper=new OperationDiv();break;default:break;}return oper;}}

客户端类：

package yx.designpattern.simpleFactory;public class Test {public static void main(String[] args) {Operation oper;oper=OperationFactory.createOperation('/');oper.number1=1;oper.number2=0;try {System.out.println(oper.getResult());} catch (Exception e) {e.printStackTrace();}}}