实验5：建造者模式

本次实验属于模仿型实验，通过本次实验学生将掌握以下内容：

1、理解建造者模式的动机，掌握该模式的结构；

2、能够利用建造者模式解决实际问题。

[实验任务]：计算机组装

使用建造者模式，完成下述任务：计算机组装工厂可以将CPU、内存、硬盘、主机等硬件设备组装在一起构成计算机，计算机的类型可以是笔记本，也可以是台式机。

类图

运行效果

 

 源代码

public class Client
{public static void main(String[] args){//动态确定电脑类型ComputerBuilder cb = (ComputerBuilder) XMLUtil.getBean();//指挥者Director director = new Director();//指挥者准备组装director.setComputerBuilder(cb);//获得组装Computer computer = director.construct();System.out.println("电脑组装");System.out.println(computer.getCpu());System.out.println(computer.getMemory());System.out.println(computer.getHardDisk());System.out.println(computer.getHost());}
}public class Computer
{private String cpu;private String memory;private String hardDisk;private String host;public String getCpu(){return cpu;}public void setCpu(String cpu){this.cpu = cpu;}public String getMemory(){return memory;}public void setMemory(String memory){this.memory = memory;}public String getHardDisk(){return hardDisk;}public void setHardDisk(String hardDisk){this.hardDisk = hardDisk;}public String getHost(){return host;}public void setHost(String host){this.host = host;}
}public abstract class ComputerBuilder
{protected Computer computer=new Computer();public abstract void buildCpu();public abstract void buildMemory();public abstract void buildHardDisk();public abstract void buildHost();public Computer getComputer(){return computer;}
}public class DesktopBuilder extends ComputerBuilder
{@Overridepublic void buildCpu(){computer.setCpu("台式机装了一个Cpu");}@Overridepublic void buildMemory(){computer.setMemory("台式机装了一个内存");}@Overridepublic void buildHardDisk(){computer.setHardDisk("台式机装了一个硬盘");}@Overridepublic void buildHost(){computer.setHost("台式机装了一个主机");}
}public class Director
{private ComputerBuilder cb;public void setComputerBuilder(ComputerBuilder cb){this.cb = cb;}public Computer construct(){cb.buildCpu();cb.buildMemory();cb.buildHardDisk();cb.buildHost();return cb.getComputer();}
}public class LaptopBuilder extends ComputerBuilder
{@Overridepublic void buildCpu(){computer.setCpu("笔记本装了一个Cpu");}@Overridepublic void buildMemory(){computer.setMemory("笔记本装了一个内存");}@Overridepublic void buildHardDisk(){computer.setHardDisk("笔记本装了一个硬盘");}@Overridepublic void buildHost(){computer.setHost("笔记本装了一个主机");}
}import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.File;public class XMLUtil
{public static Object getBean(){try{//创建DOM文档对象DocumentBuilderFactory dFactory = DocumentBuilderFactory.newInstance();DocumentBuilder builder = dFactory.newDocumentBuilder();Document doc = builder.parse(new File("src/main/resources/config5.xml"));//获取包含类名的文本节点NodeList nl = doc.getElementsByTagName("className");Node classNode = nl.item(0).getFirstChild();String cName = classNode.getNodeValue();//通过类名生成实例对象并将其返回Class c = Class.forName(cName);Object obj = c.newInstance();return obj;}catch (Exception e){e.printStackTrace();return null;}}
}

config5.xml

<?xml version="1.0" encoding="UTF-8"?><config><className>Tutorial_5.DesktopBuilder</className>
</config>