現在IndexController中的方法都只有兩個參數，request和response，和Servlet的參數保持一致。但是，這個很不Spring啊！@RequestParam,@PathValue,@ModelAtrribute,Model都嗨起來！要把這幾個嗨起來等慢慢來，本篇介紹一個最簡單也是最基本的，每個請求維護一個上下文，把request,response,session都單獨保存在SessionContext中, 也可以保存其他信息。

新增類jw-core/src/main/java/com/jw/util/SessionContext.java

package com.jw.util;

import java.util.HashMap;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

/** * *@author jay * */

public class SessionContext implements java.io.Serializable {

private static final long serialVersionUID = -8726882324373214664L;

public final static String REQUEST = "request";

public final static String RESPONSE = "response";

public final static String SESSION = "session";

private final static ThreadLocal context = new ThreadLocal();

private Map map = new HashMap();

public static SessionContext buildContext() {

context.set(new SessionContext());

return context.get();

}

public static void setContext(SessionContext ctx) {

context.set(ctx);

}

public static SessionContext getContext() {

return context.get();

}

public static void removeContext() {

context.remove();

}

public SessionContext() {

}

public static HttpServletRequest getRequest() {

return (HttpServletRequest) getContext().map.get(REQUEST);

}

public static HttpServletResponse getResponse() {

return (HttpServletResponse) getContext().map.get(RESPONSE);

}

public static HttpSession getSession() {

return (HttpSession) getContext().map.get(SESSION);

}

public boolean containsKey(String key) {

return map.containsKey(key);

}

public void put(String key, Object value) {

map.put(key, value);

}

public SessionContext set(String key, Object value) {

map.put(key, value);

return this;

}

public Object get(String key) {

return map.get(key);

}

public Object get(String key, Object defaultValue) {

if (map.containsKey(key))

return map.get(key);

return defaultValue;

}

public String getString(String key) {

return (String) map.get(key);

}

public String getString(String key, String defaultValue) {

return map.containsKey(key) ? getString(key) : defaultValue;

}

public boolean getBoolean(String key) {

return (Boolean) map.get(key);

}

public boolean getBoolean(String key, boolean defaultValue) {

return map.containsKey(key) ? getBoolean(key) : defaultValue;

}

public int getInt(String key) {

return (Integer) map.get(key);

}

public int getInt(String key, int defaultValue) {

return map.containsKey(key) ? getInt(key) : defaultValue;

}

}

修改類jw-core/src/main/java/com/jw/web/servlet/DispatcherServlet.java

保存request,response,session等信息

public void service(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {

String appName = request.getSession().getServletContext().getContextPath();

request.setAttribute("root", appName);// 在jsp頁面中添加root變量

//...

String[] paths = path.split("/", 2);

// build context

SessionContext.buildContext()

.set(SessionContext.REQUEST, request)

.set(SessionContext.RESPONSE, response)

.set(SessionContext.SESSION, request.getSession())

.set("requestUrl", path);

String controllerClazeName = ConfigUtils.getProperty("package.scan") + "." + StringUtils.upperFirst(paths[0])

+ "Controller";

String methodName = paths[1];

//...

}

上下文已經準備好了，本篇結束。

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