{"id":627,"date":"2015-05-06T10:17:47","date_gmt":"2015-05-06T02:17:47","guid":{"rendered":"https:\/\/ai.zhousir.top\/?p=627"},"modified":"2026-08-18T11:17:08","modified_gmt":"2026-08-18T03:17:08","slug":"%e5%af%b9servlet%e7%9a%84%e5%88%9d%e5%a7%8b%e5%8c%96%e7%9a%84%e7%90%86%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/ai.zhousir.top\/?p=627","title":{"rendered":"\u5bf9Servlet\u7684\u521d\u59cb\u5316\u7684\u7406\u89e3"},"content":{"rendered":"
\n

Servlet \u521d\u59cb\u5316\u65f6\uff0c\u5bb9\u5668\u4f1a\u8c03\u7528 init(ServletConfig config)<\/code> \u6216\u65e0\u53c2 init()<\/code>\u3002ServletConfig<\/code> \u662f\u63a5\u53e3\uff0c\u771f\u6b63\u7684\u5b9e\u73b0\u7c7b\u5bf9\u8c61\u7531\u5bb9\u5668\u5b9e\u4f8b\u5316<\/strong>\u540e\u518d\u4f20\u8fdb\u6765\u3002<\/p>\n

web.xml \u91cc\u7ed9 Servlet \u914d\u7684\u542f\u52a8\u53c2\u6570\uff0c\u4e5f\u4f1a\u5728\u521d\u59cb\u5316\u65f6\u88ab\u5bb9\u5668\u6536\u96c6\uff0c\u8bb0\u8fdb\u8fd9\u4efd ServletConfig<\/code>\u3002\u6240\u4ee5\u4f60\u80fd\u7528 getInitParameter<\/code> \u628a\u5b83\u4eec\u53d6\u51fa\u6765\u3002<\/p>\n

<\/p>\n

\u8981\u6ce8\u610f\u4e24\u70b9\uff1a\u521d\u59cb\u5316\u53c2\u6570\u53ea\u80fd\u662f\u5b57\u7b26\u4e32<\/strong>\uff1b\u8986\u76d6\u5e26\u53c2 init<\/code> \u65f6\u8bb0\u5f97 super.init(config)<\/code>\uff0c\u5426\u5219\u540e\u9762\u53d6\u4e0d\u5230\u914d\u7f6e\u3002<\/p>\n

\u4e00\u3001init \u7531\u8c01\u8c03\u7528<\/h2>\n

\u7ed3\u8bba\u5148\u8bf4\uff1aServletConfig \u7531\u5bb9\u5668\u5b9e\u4f8b\u5316<\/strong>\u3002\u5bb9\u5668\u6784\u9020\u5b9e\u73b0\u7c7b\u5bf9\u8c61\uff0c\u518d\u628a\u5b83\u4f20\u7ed9 Servlet\u3002GenericServlet \u7684\u5e26\u53c2 init<\/code> \u4f1a\u628a config \u5b58\u8d77\u6765\uff0c\u518d\u8c03\u65e0\u53c2 init()<\/code>\uff0c\u6240\u4ee5\u65e5\u5e38\u8986\u76d6\u65e0\u53c2\u7248\u672c\u5373\u53ef\u3002<\/p>\n

public void init(ServletConfig config) throws ServletException {\n    super.init(config);   \/\/ \u5fc5\u987b\u5148\u4ea4\u7ed9\u7236\u7c7b\u4fdd\u5b58 config\n    \/\/ \u518d\u505a\u81ea\u5df1\u7684\u4e00\u6b21\u6027\u521d\u59cb\u5316\uff1a\u8bfb\u53c2\u6570\u3001\u6253\u5f00\u8fde\u63a5\n}<\/code><\/pre>\n
\u4e8c\u3001\u521d\u59cb\u5316\u53c2\u6570\u600e\u4e48\u4f20\u5230 Servlet<\/h2>\n
\u5728 web.xml<\/code> \u91cc\u7528 <init-param><\/code> \u914d\u7f6e\u3002\u5bb9\u5668\u521d\u59cb\u5316 Servlet \u65f6\u4f1a\u6536\u96c6\u8fd9\u4e9b\u53c2\u6570\uff0c\u8bb0\u5f55\u5728 ServletConfig \u7684\u5b9e\u73b0\u7c7b\u4e2d\u3002\u4e4b\u540e\u7528\u4e0b\u9762\u4e24\u4e2a\u65b9\u6cd5\u8bfb\u53d6\uff1a<\/p>\n
public String getInitParameter(String name);\npublic Enumeration getInitParameterNames();<\/code><\/pre>\n
\u7ed3\u8bba\uff1a\u4f60\u5bf9 Servlet \u7684\u914d\u7f6e\uff0c\u5728\u521d\u59cb\u5316\u65f6\u90fd\u7531\u5bb9\u5668\u6536\u96c6\u5e76\u8bb0\u8fdb ServletConfig\u3002<\/p>\n
\u4e09\u3001\u4e00\u4e2a Servlet \u914d\u7f6e\u793a\u4f8b<\/h2>\n
\"QQ\u255c\u256a\u2550\u255d20161202093851\"<\/a><\/p>\n
\u4e0a\u56fe\u662f\u628a\u6570\u636e\u5e93\u914d\u7f6e\u6587\u4ef6\u8def\u5f84\u5199\u6210\u521d\u59cb\u5316\u53c2\u6570\u3002Servlet \u521d\u59cb\u5316\u5b8c\u6210\u540e\u53ef\u4ee5\u8fd9\u6837\u53d6\uff1a<\/p>\n
String dbconf = this.getServletConfig().getInitParameter(\"dbConfig\");<\/code><\/pre>\n
\u62ff\u5230\u7684\u53ea\u662f\u4e00\u4e2a\u5b57\u7b26\u4e32\u3002\u63a5\u4e0b\u6765\u53ef\u4ee5\u7528\u5b83\u53bb\u8bfb\u914d\u7f6e\u6587\u4ef6\uff0c\u518d\u521d\u59cb\u5316\u6570\u636e\u6e90\u3002\u4e5f\u53ef\u4ee5\u4f20\u4e00\u4e2a\u7c7b\u540d\uff0c\u518d\u7528\u53cd\u5c04\u5b9e\u4f8b\u5316\uff08\u539f\u6587 getInstance()<\/code> \u5e94\u5199\u6210 newInstance()<\/code>\uff09\uff1a<\/p>\n
\/\/ web.xml \u91cc\u914d\u7f6e\u7684\u503c\u7c7b\u4f3c\uff1acn.ittx.db.DBUtil\nString dbconf = this.getServletConfig().getInitParameter(\"dbconfig\");\nObject db = Class.forName(dbconf).newInstance();<\/code><\/pre>\n
\u7ed3\u8bba\uff1aweb.xml \u5bf9 Servlet \u7684\u521d\u59cb\u5316\uff0c\u53ea\u80fd\u4f20\u9012\u5b57\u7b26\u4e32\u7c7b\u578b\u7684\u6570\u636e\u3002<\/p>\n\n\n\n\n\n\n
\u5bf9\u8c61<\/th>\n\u8c01\u521b\u5efa<\/th>\n\u4f5c\u7528\u8303\u56f4<\/th>\n\u5178\u578b\u7528\u9014<\/th>\n<\/tr>\n<\/thead>\n
ServletConfig<\/td>\n\u5bb9\u5668\uff0c\u6bcf\u4e2a Servlet \u4e00\u4efd<\/td>\n\u5f53\u524d Servlet<\/td>\n\u8bfb <init-param>\u3001\u53d6 ServletContext<\/td>\n<\/tr>\n
ServletContext<\/td>\n\u5bb9\u5668\uff0c\u6bcf\u4e2a Web \u5e94\u7528\u4e00\u4efd<\/td>\n\u6574\u4e2a\u5e94\u7528<\/td>\n\u5171\u4eab\u5c5e\u6027\u3001\u8bfb\u4e0a\u4e0b\u6587\u53c2\u6570\u3001\u62ff\u771f\u5b9e\u8def\u5f84<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n
\u56db\u3001ServletContext<\/h2>\n
ServletContext<\/code> \u8d1f\u8d23\u548c\u300c\u4e0a\u4e0b\u6587\u300d\u4ea4\u4e92\uff1a\u5411\u4e0a\u5bf9\u63a5 Servlet \u5bb9\u5668\uff0c\u5411\u4e0b\u5bf9\u63a5\u8bf7\u6c42\u548c\u54cd\u5e94\u3002\u5728 ServletConfig \u4e0a\u8c03\u7528 getServletContext()<\/code> \u5c31\u80fd\u62ff\u5230\u5f53\u524d\u5e94\u7528\u7684\u4e0a\u4e0b\u6587\u5bf9\u8c61\u3002<\/p>\n
\u5b83\u540c\u6837\u662f\u63a5\u53e3\uff0c\u5b9e\u73b0\u5bf9\u8c61\u4e5f\u662f Servlet \u521d\u59cb\u5316\u65f6\u7531\u5bb9\u5668\u521b\u5efa\u7684\u2014\u2014\u8fd9\u70b9\u548c ServletConfig \u76f8\u540c\u3002\u5e94\u7528\u7ea7\u5171\u4eab\u6570\u636e\uff08\u4f8b\u5982\u6570\u636e\u6e90\uff09\u901a\u5e38\u653e\u5728 Context \u5c5e\u6027\u91cc\uff0c\u800c\u4e0d\u662f\u6bcf\u4e2a Servlet \u81ea\u5df1\u85cf\u4e00\u4efd\u3002<\/p>\n
\u6269\u5c55\u9605\u8bfb\uff1a\u6df1\u5165\u5206\u6790 JavaWeb Item6 \u2014\u2014 servletConfig \u4e0e servletContext<\/a>\u3002<\/p>\n
\n
\u4e00\u53e5\u8bdd\u603b\u7ed3\uff1a\u521d\u59cb\u5316\u53c2\u6570\u53ea\u662f\u5b57\u7b26\u4e32\uff1a\u5bb9\u5668\u5199\u5165 ServletConfig\uff0c\u518d\u901a\u8fc7 ServletContext \u8fde\u5230\u6574\u4e2a\u5e94\u7528\u3002<\/strong><\/p>\n<\/blockquote>\n<\/section>\n","protected":false},"excerpt":{"rendered":"
Servlet \u521d\u59cb\u5316\u65f6\uff0c\u5bb9\u5668\u4f1a\u8c03\u7528 init(ServletConfig config) \u6216\u65e0\u53c2 init( […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[60],"tags":[183,182],"_links":{"self":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/627"}],"collection":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=627"}],"version-history":[{"count":3,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/627\/revisions"}],"predecessor-version":[{"id":2169,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=\/wp\/v2\/posts\/627\/revisions\/2169"}],"wp:attachment":[{"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=627"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=627"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ai.zhousir.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=627"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}