VMware WorkStation的煩心事

時間  2019-11-24
標籤 vmware workstation 煩心事 欄目 虛擬機 简体版
原文   原文鏈接

diary_report.jpg
###Interesting things

有2天沒有寫diary report了，由於這幾天都在火車上顛簸。上個星期五晚上9點的火車從廣州到武漢，星期日在學校考試，而後晚上9點的火車又匆忙的趕回廣州。今天是8點30趕到的廣州，很累。今天老大給我佈置了一個新的Task，實現FastDFS的集羣和負載均衡。看來今天是要加班的，FastDFS對我來講是一個未知的領域，Spring Security 和 Filter、Interceptor的demo尚未寫出來。(目測又要delay)個人時間計劃表是天天6點30起牀，晚上加班到10點(正常是6點)，笨鳥先飛。html

###What did you do todayjava

  • 可插拔性，在軟件系統的設計中，可插拔是一個重要特性。它意味着給系統添加新功能的時候(或者將原來功能的實現替換成新的實現而保持接口不變)，不改變系統已有的功能。web

  • CMD (Common Module Definition)：公共模塊定義，對於模塊的依賴，CMD是延遲執行，推崇依賴就近。spring

  • 今天安裝VMware Workstation，這個玩意大學上嵌入式的時候用過(設置ip和掩碼：ifconfig eth0 192.168.1.2 netmask 255.255.255.0就是這樣用，設置的ip是一次性，重啓虛擬機後就失效， 設置網關：route add default gw 192.168.1.1)，但是在我本身的筆記本我一直用Virtural Box。用起來Vmware還真不習慣，首先遇到一個問題就是虛擬機ping不一樣主機(真尼瑪蛋疼)，因此記錄一下。vim

  • 進入虛擬機設置，把網絡鏈接設置爲橋接模式。 tomcat

    image.png

    • 點「高級」按鈕，記錄咱們的MAC地址00:0C:29:67:76:2F bash

      image.png

    • 若是/etc/sysconfig/network-scripts目錄沒有ifcfg-eth0文件，那麼咱們就建立ifcfg-eth0文件，cd /etc/sysconfig/network-scripts, touch ifcfg-eth0網絡

    • vi ifcfg-eth0 ,對這個文件進行編輯。具體的編輯內容能夠參考圖片。 session

      image.png

    • vi /etc/resolv.conf 進入resolv.conf文件設置dns。 mvc

      image.png

    • vim /etc/rc.d/rc.local，配置ifup eth0，讓開始時重啓eth0。

      image.png

    • 重啓網絡服務，service network restart

      image.png

    • 咱們滿懷期待的輸入ping 192.168.12.61(這個是主機地址)，而後結果啪啪啪打臉，根本就ping不通嘛。

      image.png

    • 左思右想一下，發現是本地防火牆開啓的問題，那麼咱們關掉防火牆再試一試。果真是防火牆的問題，草他媽。

      image.png

    • 咱們本地的防火牆確定不能關閉，那麼有沒有一種策略，能實現虛擬機ping通主機同時又保證本地防火牆保持開啓狀態呢？確定是有的，打開Windows防火牆，找到高級設置。

      image.png

    • 咱們在入站規則中找到「文件和打印機共享(回顯請求 - ICMPv4-In)」，而後啓動該規則便可解決問題。

      image.png

    • 可是咱們又發現一個問題，咱們ping不通www.baidu.com，這個問題就很操蛋了。

      image.png

    • 咱們只須要把nameserver 設置爲 114.114.114.114就能解決虛擬機ping不通外網的問題。

      image.png
      image.png

  • 關於<mvc:annotation-driven />這個問題，咱們接着上一篇博客講，我上一篇博客的觀點出自於使用@Controller註解爲何要配置<mvc:annotation-driven />，這篇博客做者的觀點是"要使用spring mvc中的@Controller註解，就必需要配置<mvc:annotation-driven />，不然org.springframework.web.servlet.DispatcherServlet沒法找到控制器並把請求分發到控制器。" 當我剛開始學習SpringMVC的時候，就看過這篇文章，這篇文章某些觀點的確解決了個人一些開發問題，可是我上面列舉的做者觀點就錯的有點離譜。 下面我就用代碼去證實這個觀點是錯的！

    • 咱們在spring-servlet註釋<mvc:annotation-driven />這一行代碼。
      image.png
    • 定義一個MvcAnnotationDrivenTestController
@RequestMapping("/mvc")
@Controller
public class MvcAnnotationDrivenTestController {

    @RequestMapping(value = "/testMvcAnnotationDriven", method = RequestMethod.GET)
    public ModelAndView testMvcAnnotationDriven() {
        return new ModelAndView("mvc_annotation_driven_test");
    }
}
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  • 在/WEB-INF/jsp/下面，定義mvc_annotation_driven_test.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
    <head>
        <title>mvc_annotation_driven_test</title>
    </head>
    <body>
        hello, this is mvc_annotation_driven_test
    </body>
</html>
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  • 咱們啓動tomcat，輸入http://localhost:8080/mvc/testMvcAnnotationDriven，咱們就證實了"使用spring mvc中的@Controller註解，就必需要配置<mvc:annotation-driven />" 這個觀點是錯的了。
    image.png
  • 接下來咱們在定義一個TestController，咱們能夠提供一個問題：「若是不在spring-servlet文件中配置<mvc:annotation-driven />，咱們能成功的去訪問http://localhost:8080/test/interceptor1這個連接嗎？」 答案是不能訪問！！！
@RestController
@RequestMapping("/test")
public class TestController {

    @GetMapping("/interceptor1")
    public String testInterceptor1(HttpSession session) {
        session.setAttribute("test1", "interceptor1");
        session.invalidate();
        return "testInterceptor1";
    }

    @GetMapping("/interceptor2")
    public String testInterceptor2(HttpSession session) {
        session.setAttribute("test2", "interceptor2");
        session.invalidate();
        return "testInterceptor2";
    }
}
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* 會拋出"[20:02:37:859] [WARN] - org.springframework.web.servlet.DispatcherServlet.noHandlerFound(DispatcherServlet.java:1176) - No mapping found for HTTP request with URI [/test/interceptor1] in DispatcherServlet with name 'filter_interceptor_mvc'"這個錯誤，形成404。
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image.png

  • 咱們能夠去官方的一些文檔找到答案。mvc:annotation-driven/實際上是毫無心義的。它聲明瞭對註解驅動(@RequestMapping, @Controller)的mvc控制器的顯式支持，儘管對這些的支持是默認行爲。
<mvc:annotation-driven /> is actually rather pointless. It declares explicit support for annotation-driven MVC controllers (i.e.@RequestMapping, @Controller, etc), even though support for those is the default behaviour.
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My advice is to always declare <context:annotation-config>, but don't bother with <mvc:annotation-driven /> unless you want JSON support via Jackson. 複製代碼

  • 我想上面的解釋能解開大家心中的疑惑。美滋滋!

  • 接下來的篇幅會講Listener、Filter、Interceptor的demo(終於能夠還債了)。

    • 建立TestInterceptor一、TestInterceptor2。
@Slf4j
public class TestInterceptor1 extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        log.info("TestInteceptor1 preHandle");

        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        log.info("TestInterceptor1 postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.info("TestInterceptor1 afterCompletion");
    }
}
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@Slf4j
public class TestInterceptor2 extends HandlerInterceptorAdapter {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        log.info("TestInterceptor2 preHandle");

        return false;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        log.info("TestInterceptor2 postHandle");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        log.info("TestInterceptor2 afterCompletion");
    }
}
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  • 建立TestFilter一、TestFilter2。
@Slf4j
public class TestFilter1 extends OncePerRequestFilter {
    private String username;
    private String password;

    public TestFilter1() {}

    public TestFilter1(String username, String password) {
        this.username = username;
        this.password = password;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException {
        log.info("TestFilter1 doFilterInternal started, username = {} , password = {} ", username, password);
        filterChain.doFilter(httpServletRequest, httpServletResponse);
        log.info("TestFilter1 doFilterInternal end, username = {} , password = {}", username, password);
    }
}

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@Slf4j
public class TestFilter2 extends OncePerRequestFilter {
    private String username;
    private String password;

    public TestFilter2() {}

    public TestFilter2(String username, String password) {
        this.username = username;
        this.password = password;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, FilterChain filterChain) throws ServletException, IOException {
        log.info("TestFilter2 doFilterInternal started");
        filterChain.doFilter(httpServletRequest, httpServletResponse);
        log.info("TestFilter2 doFilterInternal end");
    }
}
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  • 建立ContextListener、RequestListener、RequestAttributeListener、SessionListener。
@Slf4j
public class ContextListener implements ServletContextListener {

    @Override
    public void contextInitialized(ServletContextEvent servletContextEvent) {
        log.info("context initialized");
    }

    @Override
    public void contextDestroyed(ServletContextEvent servletContextEvent) {
        log.info("context destroyed");
    }

}

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@Slf4j
public class RequesListener implements ServletRequestListener {

    @Override
    public void requestDestroyed(ServletRequestEvent servletRequestEvent) {
        log.info("request destroyed");
    }

    @Override
    public void requestInitialized(ServletRequestEvent servletRequestEvent) {
        log.info("request initialized");
    }
}
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@Slf4j
public class RequestAttributeListener implements ServletRequestAttributeListener {

    @Override
    public void attributeAdded(ServletRequestAttributeEvent servletRequestAttributeEvent) {
        log.info("attribute added");
    }

    @Override
    public void attributeRemoved(ServletRequestAttributeEvent servletRequestAttributeEvent) {
        log.info("attribute removed");
    }

    @Override
    public void attributeReplaced(ServletRequestAttributeEvent servletRequestAttributeEvent) {
        log.info("attribute replaced");
    }
}
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@Slf4j
public class SessionListener implements HttpSessionListener {

    @Override
    public void sessionCreated(HttpSessionEvent httpSessionEvent) {
        log.info("session created");
    }

    @Override
    public void sessionDestroyed(HttpSessionEvent httpSessionEvent) {
        log.info("session destroyed");
    }
}
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  • 在web.xml配置Filter、Listener
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

    <display-name>filter_interceptor</display-name>
    <welcome-file-list>
        <welcome-file>cmazxiaoma.jsp</welcome-file>
    </welcome-file-list>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>
            classpath:spring-config.xml
        </param-value>
    </context-param>

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    <listener>
        <listener-class>org.springframework.web.context.ContextCleanupListener</listener-class>
    </listener>

    <listener>
        <listener-class>com.cmazxiaoma.demo.listener.ContextListener</listener-class>
    </listener>
    
    <listener>
        <listener-class>com.cmazxiaoma.demo.listener.RequesListener</listener-class>
    </listener>

    <listener>
        <listener-class>com.cmazxiaoma.demo.listener.RequestAttributeListener</listener-class>
    </listener>
    
    <listener>
        <listener-class>com.cmazxiaoma.demo.listener.SessionListener</listener-class>
    </listener>

    <servlet>
        <servlet-name>filter_interceptor_mvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-servlet.xml</param-value>
        </init-param>

        <init-param>
            <param-name>detectAllHandlerExceptionResolvers</param-name>
            <param-value>false</param-value>
        </init-param>

        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>

    <servlet-mapping>
        <servlet-name>filter_interceptor_mvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <async-supported>true</async-supported>

        <init-param>
            <param-name>encoding</param-name>
            <param-value>utf-8</param-value>
        </init-param>

        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>

    </filter>

    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    
    <filter>
        <filter-name>testFilter1</filter-name>
        <filter-class>com.cmazxiaoma.demo.filter.TestFilter1</filter-class>
        <async-supported>true</async-supported>
        
        <init-param>
            <param-name>username</param-name>
            <param-value>testFilter1</param-value>
        </init-param>

        <init-param>
            <param-name>password</param-name>
            <param-value>123</param-value>
        </init-param>
    </filter>

    <filter-mapping>
        <filter-name>testFilter1</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
    
   
    <filter>
        <filter-name>testFilter2</filter-name>
        <filter-class>com.cmazxiaoma.demo.filter.TestFilter2</filter-class>
        <async-supported>true</async-supported>

        <init-param>
            <param-name>username</param-name>
            <param-value>testFilter2</param-value>
        </init-param>

        <init-param>
            <param-name>password</param-name>
            <param-value>456</param-value>
        </init-param>
    </filter>
    
    <filter-mapping>
        <filter-name>testFilter2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>
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  • 在servlet-servlet中配置Interceptor。
<mvc:interceptors>

        <mvc:interceptor>
            <mvc:mapping path="/test/interceptor1"/>
            <bean class="com.cmazxiaoma.demo.interceptor.TestInterceptor1" />
        </mvc:interceptor>
        
        <mvc:interceptor>
            <mvc:mapping path="/test/interceptor2"/>
            <bean class="com.cmazxiaoma.demo.interceptor.TestInterceptor2" />
        </mvc:interceptor>
    </mvc:interceptors>
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  • 咱們輸入http://localhost:8080/test/interceptor1，觀看控制檯打出的log和返回的視圖。
[21:19:03:666] [INFO] - com.cmazxiaoma.demo.listener.RequesListener.requestInitialized(RequesListener.java:18) - request initialized
[21:19:03:666] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:666] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:667] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:667] [INFO] - com.cmazxiaoma.demo.filter.TestFilter1.doFilterInternal(TestFilter1.java:44) - TestFilter1 doFilterInternal started, username = testFilter1 , password = 123 
[21:19:03:667] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:667] [INFO] - com.cmazxiaoma.demo.filter.TestFilter2.doFilterInternal(TestFilter2.java:42) - TestFilter2 doFilterInternal started
[21:19:03:680] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:680] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:680] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:681] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:681] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:681] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:685] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:686] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:686] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:691] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:03:691] [INFO] - com.cmazxiaoma.demo.interceptor.TestInterceptor1.preHandle(TestInterceptor1.java:15) - TestInteceptor1 preHandle
[21:19:03:705] [INFO] - com.cmazxiaoma.demo.listener.SessionListener.sessionDestroyed(SessionListener.java:18) - session destroyed
[21:19:03:718] [INFO] - com.cmazxiaoma.demo.interceptor.TestInterceptor1.postHandle(TestInterceptor1.java:22) - TestInterceptor1 postHandle
[21:19:03:718] [INFO] - com.cmazxiaoma.demo.interceptor.TestInterceptor1.afterCompletion(TestInterceptor1.java:27) - TestInterceptor1 afterCompletion
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.filter.TestFilter2.doFilterInternal(TestFilter2.java:44) - TestFilter2 doFilterInternal end
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.filter.TestFilter1.doFilterInternal(TestFilter1.java:46) - TestFilter1 doFilterInternal end, username = testFilter1 , password = 123
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:03:719] [INFO] - com.cmazxiaoma.demo.listener.RequesListener.requestDestroyed(RequesListener.java:13) - request destroyed
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image.png

  • 咱們輸入http://localhost:8080/test/interceptor2，控制檯打出的log和返回的視圖。
    image.png 
[21:19:46:054] [INFO] - com.cmazxiaoma.demo.listener.RequesListener.requestInitialized(RequesListener.java:18) - request initialized
[21:19:46:055] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:056] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:056] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:056] [INFO] - com.cmazxiaoma.demo.filter.TestFilter1.doFilterInternal(TestFilter1.java:44) - TestFilter1 doFilterInternal started, username = testFilter1 , password = 123 
[21:19:46:056] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:057] [INFO] - com.cmazxiaoma.demo.filter.TestFilter2.doFilterInternal(TestFilter2.java:42) - TestFilter2 doFilterInternal started
[21:19:46:057] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:057] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:058] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:058] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:059] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:059] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:059] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:060] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:060] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:061] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeAdded(RequestAttributeListener.java:13) - attribute added
[21:19:46:061] [INFO] - com.cmazxiaoma.demo.interceptor.TestInterceptor2.preHandle(TestInterceptor2.java:15) - TestInterceptor2 preHandle
[21:19:46:061] [INFO] - com.cmazxiaoma.demo.filter.TestFilter2.doFilterInternal(TestFilter2.java:44) - TestFilter2 doFilterInternal end
[21:19:46:062] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:46:062] [INFO] - com.cmazxiaoma.demo.filter.TestFilter1.doFilterInternal(TestFilter1.java:46) - TestFilter1 doFilterInternal end, username = testFilter1 , password = 123
[21:19:46:062] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:46:062] [INFO] - com.cmazxiaoma.demo.listener.RequestAttributeListener.attributeRemoved(RequestAttributeListener.java:18) - attribute removed
[21:19:46:063] [INFO] - com.cmazxiaoma.demo.listener.RequesListener.requestDestroyed(RequesListener.java:13) - request destroyed
複製代碼

  • 經過對比log和返回的視圖，咱們發現了Interceptor1執行了preHandler()、postHandler()、afterCompletion()這三個方法，而Interceptor2只執行了preHandler()這個方法。經過比較它們的源碼，咱們發現了Interceptor1的preHandler()返回的是true，而Interceptor2的preHandler()返回的是false。而第一個url咱們攔截了請求，返回了視圖，第二個url咱們攔截了請求，返回沒有視圖。

  • preHandle方法是進行處理攔截用的，該方法將在Controller處理以前調用，Interceptor攔截器是鏈式的，而且能夠中斷，當返回false的時候整個請求結束。

  • 當preHandle返回true時，postHandle()纔會執行，在Controller的方法調用以後執行，可是它會在DispatcherServlet進行視圖的渲染以前執行。

  • 當preHandle返回ture纔會執行，該方法將在整個請求完成以後，也就是DispatcherServlet渲染視完畢才執行，主要做用是情理資源。

  • 從啓動日誌來看，Listener > Filter > Interceptor > Servlet，自定義Listener和Filter很簡單，也不須要講。

###What to do tomorrow

  • 明天去看FastDFS的集羣和負載均衡，Spring Security的demo又要delay了。

###Summary

笨鳥先飛

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