【XML建模】

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；

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

XML建模

XML文件如下

<?xml version="1.0" encoding="UTF-8"?>
<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>

首先有三个标签所以要建立三个类
forwardModel类

package com.model;

public class ForwardModel {
//	<forward name="failed" path="/reg.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;
	}
	
}

actionModel类

package com.model;

import java.util.HashMap;
import java.util.Map;

public class ActionModel {
//	<action path="/regAction" type="test.RegAction">
	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 void push(ForwardModel forwardModel) {
		fMap.put(forwardModel.getName(), forwardModel);
	}
	public ForwardModel pop(String name) {
		return fMap.get(name);
	}
}

configModel类

package com.model;

import java.util.HashMap;
import java.util.Map;

public class 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);
	}
	public static void main(String[] args) {
		ConfigModel configModel=new ConfigModel();
		ActionModel actionModel = configModel.pop("/loginAction");
		System.out.println(actionModel.getType());
	}
}

接下来就是设计模式中的工厂模式。

configModelFactory类

package com.model;

import java.io.InputStream;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

/**
 * 23设计模式之一
 * 设计模式是一种解决方案 就是为了处理Java中所遇到的特定的一些问题
 * 工厂模式
 * 解决什么问题呢？
 * 他是用来将资源文件生产指定的实体类
 * 好处：
 * 提高了代码的复用性
 * @author 20190528
 *
 */
public class ConfigModelFactory {
	public static ConfigModel buid() throws DocumentException {
		return  ConfigModel("config.xml");
	}
/**
 * 生产出有类容的实体类configModel
 * @param xmlPath
 * @return
 * @throws DocumentException 
 */
	private static ConfigModel ConfigModel(String xmlPath) throws DocumentException {
		// TODO Auto-generated method stub
		ConfigModel configModel=new ConfigModel();
		ActionModel actionModel=null;
		ForwardModel forwardModel=null;
		InputStream in = ConfigModelFactory.class.getResourceAsStream(xmlPath);
		SAXReader saxReader=new SAXReader();
		 Document doc=saxReader.read(in);
		 List<Element> actionEles = doc.selectNodes("/config/action");
		 for (Element actionEle : actionEles) {
			actionModel=new ActionModel();
//			给actionModel对象填充xml的action标签的类容
			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的action标签的类容
				forwardModel.setName(forwardEle.attributeValue("name"));
				forwardModel.setPath(forwardEle.attributeValue("path"));
				forwardModel.setRedirect(!"false".equals(forwardEle.attribute("redirect")));
				
				
				actionModel.push(forwardModel);
			}
			
			
			
			configModel.push(actionModel);
		}
		return configModel;
	}
	
	
}

否则测试

public static void main(String[] args) throws DocumentException {
		ConfigModel configModel=new ConfigModelFactory().buid();
		ActionModel actionModel = configModel.pop("/loginAction");
		System.out.println(actionModel.getType());
	}

测试结果

示列2 Servlet建模

xml内容：

<?xml version="1.0" encoding="UTF-8"?>
<web-app>
  <servlet>
  	<servlet-name>jrebelServlet</servlet-name>
  	<servlet-class>com.zking.xml.JrebelServlet</servlet-class>
  </servlet>
  
  <servlet-mapping>
  	<servlet-name>jrebelServlet</servlet-name>
  	<url-pattern>/jrebelServlet</url-pattern>
  </servlet-mapping>
  
  <servlet>
  	<servlet-name>jrebelServlet2</servlet-name>
  	<servlet-class>com.zking.xml.JrebelServlet2</servlet-class>
  </servlet>
  
  <servlet-mapping>
  	<servlet-name>jrebelServlet2</servlet-name>
  	<url-pattern>/jrebelServlet2</url-pattern>
  	<url-pattern>/jrebelServlet3</url-pattern>
  </servlet-mapping>
</web-app>

通过上面的学习应该知道有多少个标签就创建多少个实体类吧。那我就不一一展示了！！！

WebAppModelFactory 类

package com.Servlet;

import java.io.InputStream;
import java.util.List;

import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;

public class WebAppModelFactory {
	public static WebAppModel buildWebAppModel() {
		String xmlPath = "/web.xml";
		return buildWebAppModel(xmlPath);
	}

	/**
	 * 建模
	 * 
	 * @param xmlPath
	 * @return
	 */
	public static WebAppModel buildWebAppModel(String xmlPath) {
		InputStream in = WebAppModelFactory.class.getResourceAsStream(xmlPath);
		SAXReader saxReader = new SAXReader();
		WebAppModel webAppModel = new WebAppModel();
		try {
			Document doc = saxReader.read(in);
			/*
			 * 将servlet的标签内容填充进WebApp
			 */
			List<Element> servletEles = doc.selectNodes("/web-app/servlet");
			for (Element servletEle : servletEles) {
				ServletModel servletModel = new ServletModel();

				/*
				 * 给ServletModel填充xml的内容
				 */
				Element servletNameEle = (Element) servletEle.selectSingleNode("servlet-name");
				Element servletClassEle = (Element) servletEle.selectSingleNode("servlet-class");
				ServletNameModel servletNameModel = new ServletNameModel();
				ServletClassModel servletClassModel = new ServletClassModel();
				servletNameModel.setContext(servletNameEle.getText());
				servletClassModel.setContext(servletClassEle.getText());
				
				servletModel.setServletNameModel(servletNameModel);
				servletModel.setServletClassModel(servletClassModel);

				webAppModel.pushServletModel(servletModel);
			}

			/*
			 * 将servlet-mapping的标签内容填充进WebApp
			 */
			List<Element> servletMappingEles = doc.selectNodes("/web-app/servlet-mapping");
			for (Element servletMappingEle : servletMappingEles) {
				ServletMappingModel servletMappingModel = new ServletMappingModel();

				/*
				 * 给ServletMappingModel填充xml的内容
				 */
				Element servletNameEle = (Element) servletMappingEle.selectSingleNode("servlet-name");
				ServletNameModel servletNameModel = new ServletNameModel();
				servletNameModel.setContext(servletNameEle.getText());
				servletMappingModel.setServletNameModel(servletNameModel);
				
				List<Element> urlPatternEles = servletMappingEle.selectNodes("url-pattern");
				for (Element urlPatternEle : urlPatternEles) {
					UrlPatternModel urlPatternModel = new UrlPatternModel();
					urlPatternModel.setContext(urlPatternEle.getText());
					servletMappingModel.pushUrlPatternModel(urlPatternModel);
				}

				webAppModel.pushServletMappingModel(servletMappingModel);
			}

		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return webAppModel;
	}
	
	/**
	 * 通过浏览器输入的网址自动找到对应的后台处理类
	 * @param webAppModel	建模后的实体类
	 * @param url	浏览器访问的网址
	 * @return
	 */
	public static String getServletClassByUrl(WebAppModel webAppModel, String url) {
		String servletClass = "";
		/*
		 * 找到浏览器网址对应的servlet-name
		 */
		String servletName = "";
		List<ServletMappingModel> servletMappingModels = webAppModel.getServletMappingModels();
		for (ServletMappingModel servletMappingModel : servletMappingModels) {
			List<UrlPatternModel> urlPatternModels = servletMappingModel.getUrlPatternModels();
			for (UrlPatternModel urlPatternModel : urlPatternModels) {
				if(url.equals(urlPatternModel.getContext())) {
					ServletNameModel servletNameModel = servletMappingModel.getServletNameModel();
					servletName = servletNameModel.getContext();
				}
			}
		}
		
		/*
		 * 找到servlet-name对应的后台处理类
		 */
		List<ServletModel> servletModels = webAppModel.getServletModels();
		for (ServletModel servletModel : servletModels) {
			ServletNameModel servletNameModel = servletModel.getServletNameModel();
			if(servletName.equals(servletNameModel.getContext())) {
				ServletClassModel servletClassModel = servletModel.getServletClassModel();
				servletClass = servletClassModel.getContext();
			}
		}
		return servletClass;
	}
	
	public static void main(String[] args) {
		WebAppModel webAppModel = WebAppModelFactory.buildWebAppModel();
		String res = getServletClassByUrl(webAppModel, "/jrebelServlet");
		String res2 = getServletClassByUrl(webAppModel, "/jrebelServlet2");
		String res3 = getServletClassByUrl(webAppModel, "/jrebelServlet3");
		System.out.println(res);
		System.out.println(res2);
		System.out.println(res3);
		
	}
}

输出结果