myStruts

package com.xiaoxiong.myStruts.action;


public class UserAction {
    public String create(){
        System.out.println("create");
        return "success";
    }
    
    public String update(){
        System.out.println("update");
        return "s1";
    }
    
    public String delete(){
        System.out.println("delte");
        return "s2";
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<struts>
    <package name="xxx1" extends="struts-default" namespace="/user">
    
        <!-- http://localhost:8080/xxx/user/create -->
    
        <action name="create" class="com.xiaoxiong.myStruts.action.UserAction" method="create">
            <result name="success">/index.jsp</result>
        </action>
        
        <action name="update" class="com.xiaoxiong.myStruts.action.UserAction" method="update">
            <result name="s1"  type="redirect">/index.jsp</result>
        </action>
        
        <action name="delete" class="com.xiaoxiong.myStruts.action.UserAction" method="delete">
            <result name="s2">/index.jsp</result>
        </action>
    </package>
    
    <package name="xxx2" extends="struts-default" namespace="/user2">
    
        <!-- http://localhost:8080/xxx/user/create -->
    
        <action name="c" class="com.xiaoxiong.myStruts.action.UserAction" method="create">
            <result name="success" type="redirect">/index.jsp</result>
        </action>
        
        <action name="u" class="com.xiaoxiong.myStruts.action.UserAction" method="update">
            <result name="s1"  type="redirect">/index.jsp</result>
        </action>
        
        <action name="d" class="com.xiaoxiong.myStruts.action.UserAction" method="delete">
            <result name="s2">/index.jsp</result>
        </action>
    </package>
</struts>

package com.xiaoxiong.myStruts.entity;

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

public class Package {
    private String name;    //包名
    private String extes;  //继承的包名
    private String namespace; //根节点
    private List<Action> actionList = new ArrayList<Action>();
    
    
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getExtes() {
        return extes;
    }
    public void setExtes(String extes) {
        this.extes = extes;
    }
    public String getNamespace() {
        return namespace;
    }
    public void setNamespace(String namespace) {
        this.namespace = namespace;
    }
    public List<Action> getActionList() {
        return actionList;
    }
    public void setActionList(List<Action> actionList) {
        this.actionList = actionList;
    }
    
}

package com.xiaoxiong.myStruts.entity;

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

public class Action {
    private String name;    //action名
    private String clz;        //引用类
    private String method;    //方法集合
    private List<Result> resultList = new ArrayList<Result>();
    
    
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getClz() {
        return clz;
    }
    public void setClz(String clz) {
        this.clz = clz;
    }
    public String getMethod() {
        return method;
    }
    public void setMethod(String method) {
        this.method = method;
    }
    public List<Result> getResultList() {
        return resultList;
    }
    public void setResultList(List<Result> resultList) {
        this.resultList = resultList;
    }
    
}

package com.xiaoxiong.myStruts.entity;

public class Result {
    private String name;     //返回的结果名
    private String type;     //跳转的方式
    private String localtion;    //跳转的对象
    
    
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public String getLocaltion() {
        return localtion;
    }
    public void setLocaltion(String localtion) {
        this.localtion = localtion;
    }
    
    
}

package com.xiaoxiong.myStruts.core;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;

import com.xiaoxiong.myStruts.entity.Action;
import com.xiaoxiong.myStruts.entity.Package;
import com.xiaoxiong.myStruts.entity.Result;

/**
 * 读取struts.xml配置文件的信息
 * @author user
 *
 */
@SuppressWarnings("all")
public class Configuration {
    private List<Package> packageList = new ArrayList<Package>();
    
    //构建URI与Action配置信息之间的对照关系
    private Map uriAction = new HashMap();
    
    public Configuration() throws ParserConfigurationException, SAXException, IOException{
        //1.创建一个XML工厂类用于解析XML的工具
        DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
        //2.创建DocumentBuilder对象，这个对象用于构建XML文件
        DocumentBuilder db = dbf.newDocumentBuilder();
        //获取存放class的根路径
        String xmlPath = this.getClass().getResource("/").getPath() + "struts.xml";
        //3.利用DOM解析struts.xml文件，经过解析的文档被包装为Doucument（文档对象）
        //Doucument存储了完整的XML的DOM属性结构
        Document doc = db.parse(new File(xmlPath)); 
        //4.获取所有包的信息
        NodeList packages = doc.getElementsByTagName("package");
        //5.循环遍历包
        for (int i = 0; i < packages.getLength(); i++) {
            //获取所有包的对象
            Element pak = (Element) packages.item(i);
            //将读取到的信息封装为Package对象
            Package newpak = new Package();
            newpak.setName(pak.getAttribute("name"));   //获取包名
            newpak.setExtes(pak.getAttribute("extes")); //获取struts.xml中extends属性
            newpak.setNamespace(pak.getAttribute("namespace"));
            
            System.out.println(pak.getAttribute("name") + ":" + pak.getAttribute("extends") +
                    ":" + pak.getAttribute("namespace"));
            //获取每一个包的action对象
            NodeList actions = doc.getElementsByTagName("action");
            for (int j = 0; j < actions.getLength(); j++) {
                //获取所有action对象
                Element action = (Element)actions.item(j);
                //将读取到的信息封装为Action对象
                Action newAction = new Action();
                newAction.setName(action.getAttribute("name"));
                newAction.setClz(action.getAttribute("class"));
                newAction.setMethod(action.getAttribute("method"));
                
                System.out.println("\t" + action.getAttribute("name") + ":" 
                + action.getAttribute("class") + ":" + action.getAttribute("method"));
                System.out.println("action.getAction()："+newAction.getClz());
                //获取results节点
                NodeList results = action.getElementsByTagName("result");
                
                for (int k = 0; k < results.getLength(); k++) {
                    //获取所有result对象
                    Element result = (Element)results.item(k);
                    //将读取到的信息封装到Result对象中
                    Result newResult = new Result();
                    
                    newResult.setName(result.getAttribute("name"));
                    newResult.setType(result.getAttribute("type"));
                    newResult.setLocaltion(result.getTextContent());
                    
                    newAction.getResultList().add(newResult);
                    
                    //getTextContent()方法用于获取标签的内容
                    System.out.println("\t\t" + result.getAttribute("name") + result.getAttribute("type") +
                            ":" + result.getTextContent());
                }
                //将aciont封装到Package中
                newpak.getActionList().add(newAction);
                
                //构建URI与Action配置信息之间的对照关系
                uriAction.put(newpak.getNamespace()+"/"+newAction.getName(), newAction);
                
                System.out.println("URI与Action配置信息之间的对照关系--》"+newpak.getNamespace()+"/"+newAction.getName()+"："+newAction);
            }
            //将封装好的package对象放入packages集合
            packageList.add(newpak);
        }
    }
    
    public Map getUriAction() {
        return uriAction;
    }

    public void setUriAction(Map uriAction) {
        this.uriAction = uriAction;
    }

    public List<Package> getPackageList() {
        return packageList;
    }

    public void setPackageList(List<Package> packageList) {
        this.packageList = packageList;
    }
    
    
    public static void main(String[] args) throws ParserConfigurationException, SAXException, IOException {
        new Configuration();
    }
}

package com.xiaoxiong.myStruts.core;

import java.io.IOException;
import java.lang.reflect.Method;
import java.util.List;
import java.util.Map;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.xiaoxiong.myStruts.entity.Action;
import com.xiaoxiong.myStruts.entity.Result;

public class StrutsPrepareAndExecuteFilter implements Filter {

    @Override
    public void destroy() {
        // TODO Auto-generated method stub
        System.out.println("程序销毁");
    }

    @Override
    public void doFilter(ServletRequest arg0, ServletResponse arg1,FilterChain arg2)
            throws IOException, ServletException {
        /**
         * 获取HttpServletRequest，HttpServletResponse对象
         */
        HttpServletRequest request = (HttpServletRequest)arg0;
        HttpServletResponse response = (HttpServletResponse)arg1;
        
        //URL:统一资源定位符
        //URI:统一资源接口
        //获取URI
        String uri = request.getRequestURI();
        //Web.xml中定义的过滤其中是接收所有的类型数据
        //对JSP文件不做拦截
        if(uri.endsWith(".jsp")){
            arg2.doFilter(arg0, arg1);
            return;
        }
        
        //获取工程名
        String contextPath = request.getContextPath();
        System.out.println("获取工程名"+contextPath);
        
        //获取action接口
        String actionURI = uri.substring(contextPath.length());
        System.out.println("$$$$$$$$$$$$$$actionURI"+actionURI);
        
        try {
            //加载struts.xml文件
            Configuration conf = new Configuration();
            System.out.println("返回加载文件结果："+conf);
            //获取已配置的所有uri与action的对应信息
            Map<String, Action> actionHM = conf.getUriAction();
            System.out.println("actionHM.get(actionURI)"+actionHM.get(actionURI));
            if(actionHM.get(actionURI) != null){
                //获取与之匹配的Action
                Action action = actionHM.get(actionURI);
                //
                System.out.println("action结果为："+action);
                //获取对应的Action类
                String className = action.getClz();
                System.out.println("========="+className);
                //获取执行的method对象
                String methodName = action.getMethod();
                
                //利用反射技术动态执行相应的方法
                //获取action类对象
                Class clz = Class.forName(className);
                //实例化Action对象
                Object act = clz.newInstance();
                //获取对应的Action中的执行方法
                Method method = clz.getMethod(methodName);
                //执行配置好的Action方法
                String ret = (String)method.invoke(act);
                
                System.out.println("方法执行的返回值："+ret);
                
                //在配置的Result中查找对应的result是否存在
                List<Result> resultList = action.getResultList();
                for(Result r : resultList){
                    System.out.println("======22222r.getName():"+r.getName()+","+r.getLocaltion());
                    //查找匹配的结果
                    if(ret.equals(r.getName())){
                        if("redirect".equals(r.getType())){
                            //跳转的路径
                            System.out.println("跳转路径："+contextPath+r.getLocaltion());
                            response.sendRedirect(contextPath+r.getLocaltion());
                        }else{
                            System.out.println("转发路径："+r.getLocaltion());
                            request.getRequestDispatcher(r.getLocaltion()).forward(request, response);
                        }
                    }
                }
            }else{
                System.out.println(actionURI+"未找到匹配的Action");
            }
            
        } catch (Exception e) {
            e.printStackTrace();
        }
        
    }

    @Override
    public void init(FilterConfig arg0) throws ServletException {
        System.out.println("程序初始化");
    }

}