xml建模

1.建模的由来

就是将指定的xml字符串当作对象来操作
如果说当对一个指定的xml格式字符串完成了建模操作，
好处在于，只需要调用指定的方法就可以完成预定的字符串获取；

2.建模的思路
1、分析需要被建模的文件中有那几个对象
2、每个对象拥有的行为以及属性
3、定义对象从小到大（从里到外）
4、通过23种的设计模式中的工厂模式，解析xml生产出指定对象

好处：
提高代码的复用性

分析XML文件（有几个对象以及属性，定义对象从小到大（从里到外））

<?xml version="1.0" encoding="UTF-8"?>
<!-- config标签:可以包含0~N个action标签 -->
<config>
    <!-- action标签:可以饱含0~N个forward标签 path:以/开头的字符串,并且值必须唯一 非空 type:字符串,非空 -->
    <action path="/regAction" type="test.RegAction">
        <!-- forward标签:没有子标签; name:字符串,同一action标签下的forward标签name值不能相同 ; path:以/开头的字符串
            redirect:只能是false|true,允许空,默认值为false -->
        <forward name="failed" path="/reg.jsp" redirect="false" />
        <forward name="success" path="/login.jsp" redirect="true" />
    </action>

    <action path="/loginAction" type="test.LoginAction">
        <forward name="failed" path="/login.jsp" redirect="false" />
        <forward name="success" path="/main.jsp" redirect="true" />
    </action>

</config>

定义XML模型对象

1.ForwardModel

public class ForwardModel {
//	<forward name="failed" path="/login.jsp" redirect="false" />
	private String name;
	private String path;
	private boolean  redirect;
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPath() {
		return path;
	}
	public void setPath(String path) {
		this.path = path;
	}
	public boolean isRedirect() {
		return redirect;
	}
	public void setRedirect(boolean redirect) {
		this.redirect = redirect;
	}

　　

2.ActionModel

public class ActionModel {
//	<action path="/loginAction" type="test.LoginAction">
       private String path;
       private String type;

       private Map<String, ForwardModel> fmap=new HashMap<>();

	public String getPath() {
		return path;
	}

	public void setPath(String path) {
		this.path = path;
	}

	public String getType() {
		return type;
	}

	public void setType(String type) {
		this.type = type;
	}

	public Map<String, ForwardModel> getFmap() {
		return fmap;
	}

	public void setFmap(Map<String, ForwardModel> fmap) {
		this.fmap = fmap;
	}

	//添加
    public void push(ForwardModel forwardModel) {
    	fmap.put(forwardModel.getName(), forwardModel);
    }
    //通过name获取对象
    public ForwardModel pop(String name) {
    	return fmap.get(name);
    }
}

　　

ConfigModel

 private Map<String, ActionModel> amap=new HashMap();

   public void push(ActionModel actionModel) {
	   amap.put(actionModel.getPath(), actionModel);
   }

   public ActionModel pop(String path) {
	   return amap.get(path);
   }   

ConfigModelFactory(工厂模式用来将资源文件生产指定的实体类)

public class ConfigModelFactory {

	public static ConfigModel  build() throws Exception {
		return configModel("config.xml");
	}

	/**
	 * 生产出有内容的实体类configModel
	 * @param xmlPath
	 * @return
	 * @throws Exception
	 */
	public static ConfigModel  configModel(String xmlPath) throws Exception {
		ConfigModel configModel=new ConfigModel();
		ActionModel actionModel=null;
		ForwardModel forwardModel=null;
		InputStream in=ConfigModelFactory.class.getResourceAsStream(xmlPath);
		SAXReader sax=new SAXReader();
		Document doc=sax.read(in);
	     List<Element>  actionEles= doc.selectNodes("/config/action");
	     for (Element actionEle : actionEles) {
			actionModel=new ActionModel();
			//给actionModel对象填充xml中的action标签的内容
			actionModel.setPath(actionEle.attributeValue("path"));
			actionModel.setType(actionEle.attributeValue("type"));

			List<Element>  forwardEles=actionEle.selectNodes("forward");
			for (Element forwardEle : forwardEles) {
				forwardModel=new ForwardModel();
				//给forwardModel对象填充xml中的forward标签的内容
				forwardModel.setName(forwardEle.attributeValue("name"));
				forwardModel.setPath(forwardEle.attributeValue("path"));
				forwardModel.setRedirect(!"false".equals(forwardEle.attributeValue(("redirect"))));
//				<forward name="failed" path="/reg.jsp" redirect="false" />
			//	redirect默认是true 重定向  只有填了false才是转发
				//forwardEle.attributeValue(("redirect"))拿到的是xml中你所填的值
			//	不填  重定向  "false".equals(forwardEle.attributeValue(("redirect")))是false
			//	填 true   重定向 "false".equals(forwardEle.attributeValue(("redirect")))是false
			//	填flase 转发 "false".equals(forwardEle.attributeValue(("redirect")))true;
				actionModel.push(forwardModel);
			}
			configModel.push(actionModel);
		}
		return configModel;
	}

	public static void main(String[] args) throws Exception {
		ConfigModel configModel=ConfigModelFactory.build();
		ActionModel actionModel=configModel.pop("/loginAction");
	     ForwardModel 	forwardModel=actionModel.pop("success");
	     System.out.println( actionModel.getType());
	     System.out.println(forwardModel.getPath());

	}
}

　　对web.xml进行建模,链接https://i.cnblogs.com/Files.aspx