XML建模实列

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
           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；

建模的一个思路：

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

注：属性为String类型，子元素标签则是map的值，子元素标签的唯一标识则为map的值

  建模分两步： 

1、以面向对象的编程思想，描述xml资源文件

2、将xml文件中内容封装进model实体对象。

实列：

实列是通过对一个web.xml文件进行建模

web.xml文件信息

<?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>

分析出xml文件中的属性以及行为，创建Model（模型）对象

.分析出以下所有对象

ServletNameModel   (servlet-name)

package com.zking.ServletModel;

public class ServletNameModel {

    private String context;

    public String getContext() {
        return context;
    }

    public void setContext(String context) {
        this.context = context;
    }

}

ServletClassModel   (servlet-class)

package com.zking.ServletModel;

public class ServletClassModel {

    private String context;

    public String getContext() {
        return context;
    }

    public void setContext(String context) {
        this.context = context;
    }

}

ServletUrlpatternModel  (url-pattern)

package com.zking.ServletModel;

public class ServletUrlPatternModel {

    private String context;

    public String getContext() {
        return context;
    }

    public void setContext(String context) {
        this.context = context;
    }

}

ServletModel     (servlet)

package com.zking.ServletModel;

public class ServletModel {

    private ServletNameModel servletNameModel;
    private ServletClassModel servletClassModel;

    public ServletNameModel getServletNameModel() {
        return servletNameModel;
    }

    public void setServletNameModel(ServletNameModel servletNameModel) {
        this.servletNameModel = servletNameModel;
    }

    public ServletClassModel getServletClassModel() {
        return servletClassModel;
    }

    public void setServletClassModel(ServletClassModel servletClassModel) {
        this.servletClassModel = servletClassModel;
    }

}

ServletMappingModel   (servlet-Mapping)

package com.zking.ServletModel;

import java.util.ArrayList;
import java.util.List;

import org.w3c.dom.ls.LSInput;

public class ServletMappingModel {

    private ServletNameModel servletNameModel;
    private List<ServletUrlPatternModel> servletUrlPatternModels= new ArrayList<>();

    public ServletNameModel getServletNameModel() {
        return servletNameModel;
    }

    public void pushUrlPatternModel(ServletUrlPatternModel urlPatternModel) {
        servletUrlPatternModels.add(urlPatternModel);
    }

    public void setServletNameModel(ServletNameModel servletNameModel) {
        this.servletNameModel = servletNameModel;
    }

    public List<ServletUrlPatternModel> getServletUrlPatternModels() {
        return servletUrlPatternModels;
    }

}

ServletWebAppModel   (web-app)

package com.zking.ServletModel;

import java.util.ArrayList;
import java.util.List;

public class ServletWebAppModel {

    private List<ServletModel> servletModels=new ArrayList<>();
    private List<ServletMappingModel> servletMappingModels = new ArrayList<>();

    public List<ServletModel> getServletModels() {
        return servletModels;
    }

    public List<ServletMappingModel> getServletMappingModels() {
        return servletMappingModels;
    }

    public void pushServletModel(ServletModel servletModel) {
        servletModels.add(servletModel);
    }

    public void pushServletMappingModel(ServletMappingModel servletMappingModel) {
        servletMappingModels.add(servletMappingModel);
    }

}

用的是23种设计模式中的工厂模式，Factory

package com.zking.ServletModel;

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

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

public class ServletWebFactory {

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

    /**
     * 建模
     *
     * @param xmlPath
     * @return
     */
    public static ServletWebAppModel buildWebAppModel(String xmlPath) {
        InputStream in = ServletWebFactory.class.getResourceAsStream(xmlPath);
        SAXReader saxReader = new SAXReader();
        ServletWebAppModel webAppModel = new ServletWebAppModel();
        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) {
                    ServletUrlPatternModel urlPatternModel = new ServletUrlPatternModel();
                    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(ServletWebAppModel 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<ServletUrlPatternModel> urlPatternModels = servletMappingModel.getServletUrlPatternModels();
            for (ServletUrlPatternModel 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) {
        ServletWebAppModel webAppModel = ServletWebFactory.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);

    }

}

运行代码得到结果：