目录
[再看 ActionModel](#再看 ActionModel)
ActionDuplicateDefinitionException
ForwardDuplicateDefinitionException
用一个xml-config文件实例：
- ActionModel
- ConfigModel
- ForwardModel
- ActionNotFoundException
- ForwardNotFoundException
- ConfigModelFactory
- ActionDuplicateDefinitionException
- ForwardDuplicateDefinitionException
- InvalidPathException
先看config.xml文件
XML
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE config[
<!ELEMENT config (action*)>
<!ELEMENT action (forward*)>
<!ELEMENT forward EMPTY>
<!ATTLIST action
path CDATA #REQUIRED
type CDATA #REQUIRED
>
<!ATTLIST forward
name CDATA #REQUIRED
path CDATA #REQUIRED
redirect (true|false) "false"
>
]>
<config>
<action path="/studentAction" type="org.lisen.mvc.action.StudentAction">
<forward name="students" path="/students/studentList.jsp" redirect="false"/>
</action>
</config>再看 ActionModel
java
package com.zking.mymvc.framework;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* ActionModel类：表示一个Action的模型，包含了Action的路径、类型、转发模型、重定向等属性
* */
public class ActionModel {
private String path; //Action的路径
private String type; //Action的类型，例如：request、ajax等
private static Pattern pattern = Pattern.compile("^/.+$"); //静态的正则表达式，用于匹配Action的路径
private Map<String, ForwardModel> forwardmap = new HashMap<>(); //转发模型的HashMap
private Boolean redirect; //是否重定向
public String getPath() {
return path;
}
public void setPath(String path) {
checkPath(path); //校验Action的路径是否符合规范，即必须以/开头
this.path = path;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
// put()方法用于将ForwardModel转发模型添加到HashMap集合中；
public void put(ForwardModel forward) {
if(!forwardmap.containsKey(forward.getName())) {
forwardmap.put(forward.getName(), forward); //添加转发模型
}
else {
throw new ForwardDuplicateDefinitionException("forward name:"+forward.getName()+" 不能重复");
//如果转发模型已经存在，则抛出ForwardDuplicateDefinitionException异常
}
}
// find()方法用于查找指定名称的转发模型，如果不存在则抛出ForwardNotFoundException异常
public ForwardModel find(String name) {
if(!forwardmap.containsKey(name)) {
return forwardmap.get(name);
}
else {
throw new ForwardNotFoundException("forward name:"+name+"不存在");
//如果转发模型不存在，则抛出ForwardNotFoundException异常
}
}
// setRedirect()方法用于设置属性redirect的值必须为true或者false；
public void setRedirect(String redirect) {
if("true".equals(redirect) || "false".equals(redirect)){
this.redirect=Boolean.valueOf(redirect);
}
else {
throw new RuntimeException("属性redirect的值必须为true或者false");
//如果属性redirect的值不为true或者false，则抛出RuntimeException异常
}
}
// checkPath()方法用于校验路径是否符合规范，即必须以/开头；
public void checkPath(String path) {
Matcher matcher = pattern.matcher(path); //匹配Action的路径是否符合规范
boolean b = matcher.matches();
if(!b) {
throw new InvalidPathException("ForwardModel.path["+path+"]必须以/开头");
//如果Action的路径不符合规范，则抛出InvalidPathException异常
}
}
}ConfigModel
java
public class ConfigModel {
private Map<String, ActionModel> actionMap = new HashMap<>();
//根据指定的路径 path，在 actionMap 中查找对应的 ActionModel 对象并返回。
public ActionModel find(String path) {
if(actionMap.containsKey(path)) {
return actionMap.get(path);
}
else {
throw new RuntimeException("action path:"+path+"没有找到");
}
}
//将指定的 ActionModel 对象存储到 actionMap 中。
public void put(ActionModel action) {
if(!actionMap.containsKey(action.getPath())) {
actionMap.put(action.getPath(), action);
}
else {
//如果该对象的路径已经存在于 actionMap 中，则抛出自定义的 ActionDuplicateDefinitionException 异常，提示路径重复定义。
throw new ActionDuplicateDefinitionException("action path:"+action.getPath()+"重复定义");
}
}
}ForwardModel
java
public class ForwardModel {
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(String redirect) {
this.redirect = Boolean.valueOf(redirect);
}
}ActionNotFoundException
java
/*
* action找不到指定路径
*/
public class ActionNotFoundException extends RuntimeException{
public ActionNotFoundException() {
super();
}
public ActionNotFoundException(String msg) {
super(msg);
}
public ActionNotFoundException(String msg,Throwable cause) {
super(msg,cause);
}
}ForwardNotFoundException
java
public class ForwardModel {
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(String redirect) {
this.redirect = Boolean.valueOf(redirect);
}
}ConfigModelFactory
java
public class ConfigModelFactory {
//私有化构造方法，确保该类不会被实例化
private ConfigModelFactory() {}
//使用饿汉模式，类加载时就初始化了config对象
private static ConfigModel config = null;
static {
//读取配置文件config.xml
InputStream in = ConfigModelFactory.class.getResourceAsStream("/config.xml");
SAXReader reader = new SAXReader();
Document doc;
try {
doc = reader.read(in);
Element root = doc.getRootElement();
config = new ConfigModel();
//读取每个action节点
List<Element> actions = root.selectNodes("action");
for (Element action : actions) {
String actionPath = action.attributeValue("path");
String actionType = action.attributeValue("type");
//创建ActionModel对象
ActionModel actionModel = new ActionModel();
actionModel.setPath(actionPath);
actionModel.setType(actionType);
//读取每个action节点下的forward子节点
List<Element> forwards = action.selectNodes("forward");
for (Element forward : forwards) {
String forwardPath = forward.attributeValue("path");
String forwardName = forward.attributeValue("name");
String redirect = forward.attributeValue("redirect");
//创建ForwardModel对象
ForwardModel forwardModel = new ForwardModel();
forwardModel.setPath(forwardPath);
forwardModel.setName(forwardName);
forwardModel.setRedirect(redirect);
//将ForwardModel对象放入ActionModel对象中
actionModel.put(forwardModel);
}
//将ActionModel对象放入ConfigModel对象中
config.put(actionModel);
}
} catch (Exception e) {
//抛出运行时异常
throw new RuntimeException("解析config.xml发生异常", e.getCause());
}
}
//提供一个方法获取config对象
public static ConfigModel getConfigModel() {
return config;
}
public static void main(String[] args) throws DocumentException {
//测试
ActionModel action = config.find("/studentAction");
System.out.println(action.getType());
System.out.println("yes");
}
}ActionDuplicateDefinitionException
java
/*
* action重复定义异常
*/
public class ActionDuplicateDefinitionException extends RuntimeException{
public ActionDuplicateDefinitionException() {
super();
}
public ActionDuplicateDefinitionException(String msg) {
super(msg);
}
public ActionDuplicateDefinitionException(String msg,Throwable cause) {
super(msg,cause);
}
}ForwardDuplicateDefinitionException
java
/**
* forward重复定义异常
* @author PC
*
*/
public class ForwardDuplicateDefinitionException extends RuntimeException{
public ForwardDuplicateDefinitionException() {
super();
}
public ForwardDuplicateDefinitionException(String msg) {
super(msg);
}
public ForwardDuplicateDefinitionException(String msg,Throwable cause) {
super(msg,cause);
}InvalidPathException
java
public class InvalidPathException extends RuntimeException{
public InvalidPathException() {
super();
}
public InvalidPathException(String msg) {
super(msg);
}
public InvalidPathException(String msg,Throwable cause) {
super(msg,cause);
}