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

3、建模的好处 ：（提高代码的复用性）

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。

Demo：

config.xml

<?xml version="1.0" encoding="UTF-8"?>
<config>
<action path="/registerAction" type="test.action.RegisterAction">
<forward name="success" path="/index.jsp" redirect="true" />
<forward name="failed" path="/register.jsp" redirect="false" />
</action>
<action path="/loginAction" type="test.action.LoginAction">
<forward name="a" path="/index.jsp" redirect="false" />
<forward name="b" path="/welcome.jsp" redirect="true" />
</action>
</config>

ForwardModel

package com.zking.xml.model;

public class ForwardModel {
//	<forward name="success" path="/index.jsp" redirect="true" />
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

package com.zking.xml.model;

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

public class ActionModel {

// <action path="/loginAction" type="test.action.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 void push(ForwardModel forwardModel) {
fMap.put(forwardModel.getName(), forwardModel);
}

public ForwardModel pop(String name) {
return fMap.get(name);
}

}

ConfigModel

package com.zking.xml.model;

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

public class ConfigModel {

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

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

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

}

ConfigModelFactory : 工厂

package com.zking.xml.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;

public class ConfigModelFactory {// 工厂

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

}

public static ConfigModel build(String xmlPath) throws Exception {
ConfigModel configModel = new ConfigModel();
InputStream in = ConfigModelFactory.class.getResourceAsStream(xmlPath);
SAXReader saxReader = new SAXReader();
Document doc = saxReader.read(in);
ActionModel actionModel = null;
ForwardModel forwardModel = null;
List<Element> actionEles = doc.selectNodes("/config/action");
for (Element actionEle : actionEles) {
actionModel = new ActionModel();
// 接下来需要往actionModel中填充内容
actionModel.setPath(actionEle.attributeValue("path"));
actionModel.setType(actionEle.attributeValue("type"));
configModel.push(actionModel);

List<Element> forwardEles = actionEle.selectNodes("forward");
for (Element forwardEle : forwardEles) {
forwardModel = new ForwardModel();
// 接下来需要往forwardModel中填充内容
forwardModel.setName(forwardEle.attributeValue("name"));
forwardModel.setPath(forwardEle.attributeValue("path"));
forwardModel.setRedirect(!"false".equals(forwardEle.attributeValue("redirect")));
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");
System.out.println(actionModel.getType());
ForwardModel forwardModel = actionModel.pop("b");
System.out.println(forwardModel.getPath() + "    " + forwardModel.isRedirect());

}

}

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