{"id":2627,"date":"2022-12-15T21:57:01","date_gmt":"2022-12-15T13:57:01","guid":{"rendered":"https:\/\/qaqaq.top\/?p=2627"},"modified":"2022-12-19T20:50:10","modified_gmt":"2022-12-19T12:50:10","slug":"filter-filter%e8%bf%87%e6%bb%a4%e5%99%a8%e7%9a%84%e5%9f%ba%e6%9c%ac%e4%bd%bf%e7%94%a8%e7%a4%ba%e4%be%8b%e3%80%81filter-%e5%ae%8c%e6%95%b4%e7%9a%84%e7%94%a8%e6%88%b7%e7%99%bb%e5%bd%95%e5%92%8c%e6%9d%83","status":"publish","type":"post","link":"https:\/\/qaqaq.top\/?p=2627","title":{"rendered":"Filter-\u4ec0\u4e48\u662fFilter\u8fc7\u6ee4\u5668\u3001Filter\u8fc7\u6ee4\u5668\u7684\u57fa\u672c\u4f7f\u7528\u793a\u4f8b\u3001\u5b8c\u6574\u7684\u7528\u6237\u767b\u5f55\u548c\u6743\u9650\u68c0\u67e5\u3001Filter\u7684\u751f\u547d\u5468\u671f\u3001FilterConfig\u7c7b\u4ecb\u7ecd\u3001FilterChain\u591a\u4e2a\u8fc7\u6ee4\u5668\u6267\u884c\u7684\u7ec6\u8282\u3001Filter\u62e6\u622a\u8def\u5f84\u7684\u4e09\u79cd\u914d\u7f6e\u65b9\u5f0f"},"content":{"rendered":"\n

Filter \u8fc7\u6ee4\u5668<\/h1>\n\n\n\n

1\u3001Filter \u4ec0\u4e48\u662f\u8fc7\u6ee4\u5668<\/h2>\n\n\n\n

1\u3001Filter \u8fc7\u6ee4\u5668\u5b83\u662f JavaWeb \u7684\u4e09\u5927\u7ec4\u4ef6\u4e4b\u4e00\u3002\u4e09\u5927\u7ec4\u4ef6\u5206\u522b\u662f\uff1aServlet \u7a0b\u5e8f\u3001Listener \u76d1\u542c\u5668\u3001Filter \u8fc7\u6ee4\u5668
2\u3001Filter \u8fc7\u6ee4\u5668\u5b83\u662f JavaEE \u7684\u89c4\u8303\u3002\u4e5f\u5c31\u662f\u63a5\u53e3
3\u3001Filter \u8fc7\u6ee4\u5668\u5b83\u7684\u4f5c\u7528\u662f\uff1a\u62e6\u622a\u8bf7\u6c42\uff0c\u8fc7\u6ee4\u54cd\u5e94\u3002<\/p>\n\n\n\n

\u62e6\u622a\u8bf7\u6c42\u5e38\u89c1\u7684\u5e94\u7528\u573a\u666f\u6709\uff1a
1\u3001\u6743\u9650\u68c0\u67e5
2\u3001\u65e5\u8bb0\u64cd\u4f5c
3\u3001\u4e8b\u52a1\u7ba1\u7406
\u2026\u2026\u7b49\u7b49<\/p>\n\n\n\n

2\u3001Filter \u7684\u521d\u4f53\u9a8c<\/h2>\n\n\n\n

\u8981\u6c42\uff1a\u5728\u4f60\u7684 web \u5de5\u7a0b\u4e0b\uff0c\u6709\u4e00\u4e2a admin \u76ee\u5f55\u3002\u8fd9\u4e2a admin \u76ee\u5f55\u4e0b\u7684\u6240\u6709\u8d44\u6e90\uff08html \u9875\u9762\u3001jpg \u56fe\u7247\u3001jsp \u6587\u4ef6\u3001\u7b49\u7b49\uff09\u90fd\u5fc5\u987b\u662f\u7528\u6237\u767b\u5f55\u4e4b\u540e\u624d\u5141\u8bb8\u8bbf\u95ee\u3002<\/p>\n\n\n\n

\u601d\u8003\uff1a\u6839\u636e\u4e4b\u524d\u6211\u4eec\u5b66\u8fc7\u5185\u5bb9\u3002\u6211\u4eec\u77e5\u9053\uff0c\u7528\u6237\u767b\u5f55\u4e4b\u540e\u90fd\u4f1a\u628a\u7528\u6237\u767b\u5f55\u7684\u4fe1\u606f\u4fdd\u5b58\u5230 Session \u57df\u4e2d\u3002\u6240\u4ee5\u8981\u68c0\u67e5\u7528\u6237\u662f\u5426\u767b\u5f55\uff0c\u53ef\u4ee5\u5224\u65ad Session \u4e2d\u5426\u5305\u542b\u6709\u7528\u6237\u767b\u5f55\u7684\u4fe1\u606f\u5373\u53ef\uff01\uff01\uff01<\/p>\n\n\n\n

    <%\n        System.out.println(\"a.jsp\u9875\u9762\u6267\u884c\u4e86\");\n        Object user = session.getAttribute(\"user\");\n\n        \/\/ \u5982\u679c\u7b49\u4e8enull\uff0c\u8bf4\u660e\u8fd8\u6ca1\u6709\u767b\u5f55\n        if (user == null) {\n            request.getRequestDispatcher(\"\/login.jsp\").forward(request,response);\n            return;\n        }\n    %><\/code><\/pre>\n\n\n\n
Filter \u7684\u5de5\u4f5c\u6d41\u7a0b\u56fe\uff1a<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
Filter \u7684\u4ee3\u7801\uff1a<\/p>\n\n\n\n
package top.qaqaq.filter;\n\nimport jakarta.servlet.*;\nimport jakarta.servlet.http.HttpServletRequest;\nimport jakarta.servlet.http.HttpSession;\n\nimport java.io.IOException;\n\n\/**\n * @author RichieZhang\n * @create 2022-12-15 \u4e0b\u5348 6:28\n *\/\npublic class AdminFilter implements Filter {\n\n    \/**\n     * doFilter\u65b9\u6cd5\uff0c\u4e13\u95e8\u7528\u4e8e\u62e6\u622a\u8bf7\u6c42\u3002\u53ef\u4ee5\u505a\u6743\u9650\u68c0\u67e5\n     * @param servletRequest\n     * @param servletResponse\n     * @param filterChain\n     * @throws IOException\n     * @throws ServletException\n     *\/\n    @Override\n    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {\n\n        HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;\n\n        HttpSession session = httpServletRequest.getSession();\n        Object user = session.getAttribute(\"user\");\n        \/\/ \u5982\u679c\u7b49\u4e8enull\uff0c\u8bf4\u660e\u8fd8\u6ca1\u6709\u767b\u5f55\n        if (user == null) {\n            servletRequest.getRequestDispatcher(\"\/login.jsp\").forward(servletRequest,servletResponse);\n            return;\n        } else {\n            \/\/ \u8ba9\u7a0b\u5e8f\u7ee7\u7eed\u5f80\u4e0b\u8bbf\u95ee\u7528\u6237\u7684\u76ee\u6807\u8d44\u6e90\n            filterChain.doFilter(servletRequest,servletResponse);\n        }\n    }\n\n}\n<\/code><\/pre>\n\n\n\n
web.xml \u4e2d\u7684\u914d\u7f6e\uff1a<\/p>\n\n\n\n
    <!-- filter\u6807\u7b7e\u7528\u4e8e\u914d\u7f6e\u4e00\u4e2aFilter\u8fc7\u6ee4\u5668 -->\n    <filter>\n        <!-- \u7ed9filter\u8d77\u4e00\u4e2a\u522b\u540d -->\n        <filter-name>AdminFilter<\/filter-name>\n        <!-- \u914d\u7f6efilter\u7684\u5168\u7c7b\u540d -->\n        <filter-class>top.qaqaq.filter.AdminFilter<\/filter-class>\n    <\/filter>\n    <!-- filter-mapping\u914d\u7f6eFilter\u8fc7\u6ee4\u5668\u7684\u62e6\u622a\u8def\u5f84 -->\n    <filter-mapping>\n        <!-- filter-name\u8868\u793a\u5f53\u524d\u7684\u62e6\u622a\u8def\u5f84\u7ed9\u54ea\u4e2afilter\u4f7f\u7528 -->\n        <filter-name>AdminFilter<\/filter-name>\n        <!-- url-pattern\u914d\u7f6e\u62e6\u622a\u8def\u5f84\n            \/ \u8868\u793a\u8bf7\u6c42\u5730\u5740\u4e3a\uff1ahttp:\/\/ip:port\/\u5de5\u7a0b\u8def\u5f84\/  \u6620\u5c04\u5230IDEA \u7684 web\u76ee\u5f55\n            \/admin\/* \u8868\u793a\u8bf7\u6c42\u5730\u5740\u4e3a\uff1ahttp:\/\/ip:port\/\u5de5\u7a0b\u8def\u5f84\/admin\/*\n         -->\n        <url-pattern>\/admin\/*<\/url-pattern>\n    <\/filter-mapping><\/code><\/pre>\n\n\n\n
Filter \u8fc7\u6ee4\u5668\u7684\u4f7f\u7528\u6b65\u9aa4\uff1a
1\u3001\u7f16\u5199\u4e00\u4e2a\u7c7b\u53bb\u5b9e\u73b0 Filter \u63a5\u53e3
2\u3001\u5b9e\u73b0\u8fc7\u6ee4\u65b9\u6cd5 doFilter()
3\u3001\u5230 web.xml \u4e2d\u53bb\u914d\u7f6e Filter \u7684\u62e6\u622a\u8def\u5f84<\/p>\n\n\n\n
\u5b8c\u6574\u7684\u7528\u6237\u767b\u5f55<\/p>\n\n\n\n
login.jsp \u9875\u9762 == \u767b\u5f55\u8868\u5355<\/p>\n\n\n\n
<%--\n  Created by IntelliJ IDEA.\n  User: ZRich\n  Date: 2022\/12\/15\n  Time: \u4e0b\u5348 6:18\n  To change this template use File | Settings | File Templates.\n--%>\n<%@ page contentType=\"text\/html;charset=UTF-8\" language=\"java\" %>\n<html>\n<head>\n    <title>Title<\/title>\n<\/head>\n<body>\n    \u8fd9\u662f\u767b\u5f55\u9875\u9762\u3002login.jsp\u9875\u9762 <br\/>\n    <form action=\"http:\/\/localhost:8080\/JavaWeb_Code_Filter\/loginServlet\" method=\"get\">\n        \u7528\u6237\u540d\uff1a<input type=\"text\" name=\"username\" \/> <br\/>\n        \u5bc6\u7801\uff1a<input type=\"password\" name=\"password\" \/> <br\/>\n        <input type=\"submit\">\n    <\/form>\n<\/body>\n<\/html>\n<\/code><\/pre>\n\n\n\n
LoginServlet \u7a0b\u5e8f<\/p>\n\n\n\n
package top.qaqaq.servlet;\n\nimport jakarta.servlet.ServletException;\nimport jakarta.servlet.http.HttpServlet;\nimport jakarta.servlet.http.HttpServletRequest;\nimport jakarta.servlet.http.HttpServletResponse;\n\nimport java.io.IOException;\n\n\/**\n * @author RichieZhang\n * @create 2022-12-15 \u4e0b\u5348 7:09\n *\/\npublic class LoginServlet extends HttpServlet {\n\n    @Override\n    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {\n\n        resp.setContentType(\"text\/html; charset=UTF-8\");\n\n        String username = req.getParameter(\"username\");\n        String password = req.getParameter(\"password\");\n\n        if (\"qaqaq\".equals(username) && \"123456\".equals(password)) {\n            req.getSession().setAttribute(\"user\",username);\n            resp.getWriter().write(\"\u767b\u5f55 \u6210\u529f\uff01\uff01\uff01\");\n        } else {\n            req.getRequestDispatcher(\"\/login.jsp\").forward(req,resp);\n        }\n\n    }\n}\n<\/code><\/pre>\n\n\n\n
3\u3001Filter \u7684\u751f\u547d\u5468\u671f<\/h2>\n\n\n\n
Filter \u7684\u751f\u547d\u5468\u671f\u5305\u542b\u51e0\u4e2a\u65b9\u6cd5<\/p>\n\n\n\n
1\u3001\u6784\u9020\u5668\u65b9\u6cd5<\/p>\n\n\n\n
2\u3001init \u521d\u59cb\u5316\u65b9\u6cd5
\u7b2c 1\uff0c2 \u6b65\uff0c\u5728 web \u5de5\u7a0b\u542f\u52a8\u7684\u65f6\u5019\u6267\u884c\uff08Filter \u5df2\u7ecf\u521b\u5efa\uff09<\/p>\n\n\n\n
3\u3001doFilter \u8fc7\u6ee4\u65b9\u6cd5
\u7b2c 3 \u6b65\uff0c\u6bcf\u6b21\u62e6\u622a\u5230\u8bf7\u6c42\uff0c\u5c31\u4f1a\u6267\u884c<\/p>\n\n\n\n
4\u3001destroy \u9500\u6bc1
\u7b2c 4 \u6b65\uff0c\u505c\u6b62 web \u5de5\u7a0b\u7684\u65f6\u5019\uff0c\u5c31\u4f1a\u6267\u884c\uff08\u505c\u6b62 web \u5de5\u7a0b\uff0c\u4e5f\u4f1a\u9500\u6bc1 Filter \u8fc7\u6ee4\u5668\uff09<\/p>\n\n\n\n
4\u3001FilterConfig \u7c7b<\/h2>\n\n\n\n
FilterConfig \u7c7b\u89c1\u540d\u77e5\u4e49\uff0c\u5b83\u662f Filter \u8fc7\u6ee4\u5668\u7684\u914d\u7f6e\u6587\u4ef6\u7c7b\u3002
Tomcat \u6bcf\u6b21\u521b\u5efa Filter \u7684\u65f6\u5019\uff0c\u4e5f\u4f1a\u540c\u65f6\u521b\u5efa\u4e00\u4e2a FilterConfig \u7c7b\uff0c\u8fd9\u91cc\u5305\u542b\u4e86 Filter \u914d\u7f6e\u6587\u4ef6\u7684\u914d\u7f6e\u4fe1\u606f\u3002<\/p>\n\n\n\n
FilterConfig \u7c7b\u7684\u4f5c\u7528\u662f\u83b7\u53d6 filter \u8fc7\u6ee4\u5668\u7684\u914d\u7f6e\u5185\u5bb9
1\u3001\u83b7\u53d6 Filter \u7684\u540d\u79f0 filter-name \u7684\u5185\u5bb9
2\u3001\u83b7\u53d6\u5728 Filter \u4e2d\u914d\u7f6e\u7684 init-param \u521d\u59cb\u5316\u53c2\u6570
3\u3001\u83b7\u53d6 ServletContext \u5bf9\u8c61<\/p>\n\n\n\n
java \u4ee3\u7801\uff1a<\/p>\n\n\n\n
    @Override\n    public void init(FilterConfig filterConfig) throws ServletException {\n\/\/        Filter.super.init(filterConfig);\n        System.out.println(\"2.Filter\u7684init(FilterConfig filterConfig)\u521d\u59cb\u5316\");\n\n        \/\/ 1. \u83b7\u53d6Filter\u7684\u540d\u79f0 filter-name\u7684\u5185\u5bb9\n        System.out.println(\"filter-name\u7684\u503c\u662f\uff1a\" + filterConfig.getFilterName());\n        \/\/ 2. \u83b7\u53d6\u5728web.xml\u4e2d\u914d\u7f6e\u7684init-param\u521d\u59cb\u5316\u53c2\u6570\n        System.out.println(\"\u521d\u59cb\u5316\u53c2\u6570username\u7684\u503c\u662f\uff1a\" + filterConfig.getInitParameter(\"username\"));\n        System.out.println(\"\u521d\u59cb\u5316\u53c2\u6570url\u7684\u503c\u662f\uff1a\" + filterConfig.getInitParameter(\"url\"));\n        \/\/ 3. \u83b7\u53d6ServletContext\u5bf9\u8c61\n        System.out.println(filterConfig.getServletContext());\n    }<\/code><\/pre>\n\n\n\n
web.xml \u914d\u7f6e\uff1a<\/p>\n\n\n\n
    <!-- filter\u6807\u7b7e\u7528\u4e8e\u914d\u7f6e\u4e00\u4e2aFilter\u8fc7\u6ee4\u5668 -->\n    <filter>\n        <!-- \u7ed9filter\u8d77\u4e00\u4e2a\u522b\u540d -->\n        <filter-name>AdminFilter<\/filter-name>\n        <!-- \u914d\u7f6efilter\u7684\u5168\u7c7b\u540d -->\n        <filter-class>top.qaqaq.filter.AdminFilter<\/filter-class>\n        <init-param>\n            <param-name>username<\/param-name>\n            <param-value>root<\/param-value>\n        <\/init-param>\n        <init-param>\n            <param-name>url<\/param-name>\n            <param-value>jdbc:mysql:\/\/localhost:3306\/test<\/param-value>\n        <\/init-param>\n    <\/filter><\/code><\/pre>\n\n\n\n
5\u3001FilterChain \u8fc7\u6ee4\u5668\u94fe<\/h2>\n\n\n\n
Filter             \u8fc7\u6ee4\u5668
Chain            \u94fe\uff0c\u94fe\u6761
FilterChain    \u5c31\u662f\u8fc7\u6ee4\u5668\u94fe\uff08\u591a\u4e2a\u8fc7\u6ee4\u5668\u5982\u4f55\u4e00\u8d77\u5de5\u4f5c\uff09<\/p>\n\n\n\n
\"\"<\/div><\/figure>\n\n\n\n
6\u3001Filter \u7684\u62e6\u622a\u8def\u5f84<\/h2>\n\n\n\n
–\u7cbe\u786e\u5339\u914d<\/p>\n\n\n\n
<url-pattern>\/target.jsp<\/url-pattern>\n\u4ee5\u4e0a\u914d\u7f6e\u7684\u8def\u5f84\uff0c\u8868\u793a\u8bf7\u6c42\u5730\u5740\u5fc5\u987b\u4e3a\uff1ahttp:\/\/ip:port\/\u5de5\u7a0b\u8def\u5f84\/target.jsp<\/code><\/pre>\n\n\n\n
–\u76ee\u5f55\u5339\u914d<\/p>\n\n\n\n
<url-pattern>\/admin\/*<\/url-pattern>\n\u4ee5\u4e0a\u914d\u7f6e\u7684\u8def\u5f84\uff0c\u8868\u793a\u8bf7\u6c42\u5730\u5740\u5fc5\u987b\u4e3a\uff1ahttp:\/\/ip:port\/\u5de5\u7a0b\u8def\u5f84\/admin\/*<\/code><\/pre>\n\n\n\n
–\u540e\u7f00\u540d\u5339\u914d<\/p>\n\n\n\n
<url-pattern>*.html<\/url-pattern>\n\u4ee5\u4e0a\u914d\u7f6e\u7684\u8def\u5f84\uff0c\u8868\u793a\u8bf7\u6c42\u5730\u5740\u5fc5\u987b\u4ee5.html \u7ed3\u5c3e\u624d\u4f1a\u62e6\u622a\u5230\n<url-pattern>*.do<\/url-pattern>\n\u4ee5\u4e0a\u914d\u7f6e\u7684\u8def\u5f84\uff0c\u8868\u793a\u8bf7\u6c42\u5730\u5740\u5fc5\u987b\u4ee5.do \u7ed3\u5c3e\u624d\u4f1a\u62e6\u622a\u5230\n<url-pattern>*.action<\/url-pattern>\n\u4ee5\u4e0a\u914d\u7f6e\u7684\u8def\u5f84\uff0c\u8868\u793a\u8bf7\u6c42\u5730\u5740\u5fc5\u987b\u4ee5.action \u7ed3\u5c3e\u624d\u4f1a\u62e6\u622a\u5230<\/code><\/pre>\n\n\n\n
Filter \u8fc7\u6ee4\u5668\u5b83\u53ea\u5173\u5fc3\u8bf7\u6c42\u7684\u5730\u5740\u662f\u5426\u5339\u914d\uff0c\u4e0d\u5173\u5fc3\u8bf7\u6c42\u7684\u8d44\u6e90\u662f\u5426\u5b58\u5728\uff01\uff01\uff01<\/p>\n\n\n\n
7\u3001\u4e66\u57ce\u7b2c\u516b\u9636\u6bb5\uff1a<\/h1>\n\n\n\n
1\u3001\u4f7f\u7528 Filter \u8fc7\u6ee4\u5668\u62e6\u622a\/pages\/manager\/\u6240\u6709\u5185\u5bb9\uff0c\u5b9e\u73b0\u6743\u9650\u68c0\u67e5<\/h2>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
Filter \u8fc7\u6ee4\u5668 1\u3001Filter \u4ec0\u4e48\u662f\u8fc7\u6ee4\u5668 1\u3001Filter \u8fc7\u6ee4\u5668\u5b83\u662f JavaWeb \u7684\u4e09\u5927\u7ec4\u4ef6 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[59],"tags":[61],"class_list":["post-2627","post","type-post","status-publish","format-standard","hentry","category-javaweb-code","tag-javaweb"],"_links":{"self":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/2627"}],"collection":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2627"}],"version-history":[{"count":4,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/2627\/revisions"}],"predecessor-version":[{"id":2727,"href":"https:\/\/qaqaq.top\/index.php?rest_route=\/wp\/v2\/posts\/2627\/revisions\/2727"}],"wp:attachment":[{"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2627"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2627"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/qaqaq.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2627"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}