源碼調試tomcat

1.直接通過github搜索tomcat，正好找到一位有部分翻譯內容的版本，直接fork並下載

git clone https://github.com/codefollower/Tomcat-Research.git

2.轉換成eclipse項目工程，如果沒有安裝maven，可以先配置maven環境變數

sudo  mvn eclipse:eclipse 

3.在eclipse中導入
File->Import->General->Existing Projects into Workspace

4.導入後的效果如圖所示

5.Eclipse中右擊start-tomcat.launch這個文件，點Run As啟動Tomcat，點Debug As可以調試Tomcat

6.效果如圖所示

7.啟動後通過地址http://127.0.0.1:8080/訪問

8.這時候通過上文的類似Manager App打開無法訪問(http://www.cnblogs.com/lixiaojiao-hit/p/5095180.html)

9.直接webapp目錄下的manager host-manager docs目錄放到launch/webapps目錄下

10.並按照上文中的配置進行修改，在tomcat-users.xml中進行相關配置

　　 <role rolename="tomcat" />
    <role rolename="role1" />
    <user username="tomcat" password="tomcat"
        roles="tomcat,admin,manager,manager-gui,manager-script,manager-jax,manager-status,admin-gui" />
    <user username="both" password="tomcat" roles="tomcat,role1" />
    <user username="role1" password="tomcat" roles="role1" />

11.這時候訪問查看manager app頁面就可以訪問了

12.隨便點擊按鈕，調試一下源碼，比如stop應用，審查一下源代碼

13.發現訪問路徑為/manager/html/stop?path=/docs&org.apache.catalina.filters.CSRF_NONCE=95AC2B2A81FB328CA52AF996C7F02EB4

14.查看下後臺日誌，切換到apache-tomcat-8.0.30/logs目錄下看下日誌，tail -f 10000 localhost_access_log.2016-01-03.txt

15.那麼找到web.xml中找到相關配置文件

<servlet>
    <servlet-name>Manager</servlet-name>
    <servlet-class>org.apache.catalina.manager.ManagerServlet</servlet-class>
    <init-param>
      <param-name>debug</param-name>
      <param-value>2</param-value>
    </init-param>
 </servlet>

16.發現相關servlet為ManagerServlet，打開ManagerServlet.java文件後發現相關代碼

17.找到stop代碼，直接停止到相對應的context也就是web應用

 1  protected void stop(PrintWriter writer, ContextName cn,
 2             StringManager smClient) {
 3 
 4         if (debug >= 1)
 5             log("stop: Stopping web application '" + cn + "'");
 6 
 7         if (!validateContextName(cn, writer, smClient)) {
 8             return;
 9         }
10 
11         String displayPath = cn.getDisplayName();
12 
13         try {
14             Context context = (Context) host.findChild(cn.getName());
15             if (context == null) {
16                 writer.println(smClient.getString("managerServlet.noContext",
17                         RequestUtil.filter(displayPath)));
18                 return;
19             }
20             // It isn't possible for the manager to stop itself
21             if (context.getName().equals(this.context.getName())) {
22                 writer.println(smClient.getString("managerServlet.noSelf"));
23                 return;
24             }
25             context.stop();
26             writer.println(smClient.getString(
27                     "managerServlet.stopped", displayPath));
28         } catch (Throwable t) {
29             ExceptionUtils.handleThrowable(t);
30             log("ManagerServlet.stop[" + displayPath + "]", t);
31             writer.println(smClient.getString("managerServlet.exception",
32                     t.toString()));
33         }
34 
35     }