{"id":1406,"date":"2018-07-29T21:59:57","date_gmt":"2018-07-29T13:59:57","guid":{"rendered":"https:\/\/www.xiaobo.li\/?p=1406"},"modified":"2018-07-29T22:01:03","modified_gmt":"2018-07-29T14:01:03","slug":"jsp-el","status":"publish","type":"post","link":"https:\/\/www.xiaobo.li\/notes\/archives\/1406","title":{"rendered":"Jsp EL"},"content":{"rendered":"
\n

1\u3001\u4ec0\u4e48\u662fEL<\/strong><\/h3>\n<\/div>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 EL\u662fJSP\u8868\u8fbe\u5f0f\u8bed\u8a00\uff0c\u5168\u79f0\u662fExpressionLanguage\uff0c\u4f7f\u7528EL\u7684\u76ee\u7684\u662f\u7b80\u5316\u5728JSP\u4e2d\u8bbf\u95ee\u53d8\u91cf\u7684\u65b9\u5f0f\uff0c\u7b80\u5355\u9759\u6001HTML\u4e0eJava\u4ee3\u7801\u7684\u8026\u5408\u3002<\/div>\n
<\/div>\n
\n
\n

2\u3001JSP EL\u00a0\u8868\u8fbe\u5f0f\u7528\u4e8e\u4ee5\u4e0b\u60c5\u5f62<\/strong><\/h3>\n<\/div>\n
\u9759\u6001\u6587\u672c<\/div>\n
\u6807\u51c6\u6807\u7b7e\u548c\u81ea\u5b9a\u4e49\u6807\u7b7e<\/div>\n
\u5b89\u88c5\u652f\u6301Servlet2.4\/JSP2.0\u7684Container<\/div>\n<\/div>\n
<\/div>\n
\n
\n

3\u3001\u57fa\u672c\u8bed\u6cd5\u683c\u5f0f<\/strong><\/h3>\n<\/div>\n

${ EL Expression}<\/p>\n

\u793a\u4f8b\uff1a<\/div>\n
${ \u201cHelloworld\u201d }\u00a0\u00a0\/\/\u8f93\u51fa\u5b57\u7b26\u4e32\u5e38\u91cf<\/div>\n
${\u00a0str\u00a0}\u00a0\u00a0\/\/\u8f93\u51fa\u5b57\u7b26\u4e32\u53d8\u91cfstr\u7684\u503c<\/div>\n
${ 3 + 2 }\u00a0\u00a0\/\/\u8f93\u51fa3+2\u7684\u7ed3\u679c<\/div>\n
${ user.name}\u00a0\/\/\u8f93\u51fauser\u5bf9\u8c61\u7684name\u5c5e\u6027<\/div>\n
${user[\u201cname\u201d] }\u00a0\u00a0\/\/\u540c\u4e0a<\/div>\n
${\u00a0sessionScope[\u201cuser\u201d].name }\u00a0\/\/\u540c\u4e0a<\/div>\n
${user.name}<\/div>\n
\u8bbf\u95ee\u5bf9\u8c61user\u7684getName()\u65b9\u6cd5\u4ee5\u5f97\u5230name\u6210\u5458\u7684\u503c\u3002<\/div>\n
${list[1]}<\/div>\n
\u8bbf\u95eelist\u5bf9\u8c61\u7684\u7b2c\u4e8c\u9879\u3002<\/div>\n
${map[\u201ckey\u201d]}<\/div>\n
\u8bbf\u95eemap\u6307\u5b9a\u952e\u7684\u503c\u3002<\/div>\n<\/div>\n
<\/div>\n
\n
\n

4\u3001\u64cd\u4f5c\u7b26<\/strong><\/h3>\n<\/div>\n
\u7b97\u672f\u64cd\u4f5c\u7b26(+,-,*,\/,%)<\/div>\n
\u903b\u8f91\u64cd\u4f5c\u7b26(&&,||,!\u6216and,or,not)<\/div>\n
XML\u64cd\u4f5c\u7b26<\/div>\n
lt\u00a0\u00a0<<\/div>\n
le\u00a0\u00a0<=<\/div>\n
gt\u00a0\u00a0\u00a0><\/div>\n
ge\u00a0\u00a0>=<\/div>\n
\u6bd4\u8f83\u64cd\u4f5c\u7b26(>,>=,<,<=,==,!==)\u2014\u53ef\u4ee5\u81ea\u52a8\u8f6c\u6362\u6570\u636e\u7c7b\u578b<\/div>\n
\u7a7a\u64cd\u4f5c\u7b26(empty)\/\/\u5f53\u503c\u4e3anull\u65f6\u8fd4\u56detrue<\/p>\n

EL\u7684\u7b97\u672f\u8fd0\u7b97\u7b26\u548cJava<\/a>\u4e2d\u7684\u8fd0\u7b97\u7b26\u7684\u5927\u81f4\u76f8\u540c\uff0c\u4f18\u5148\u7ea7\u4e5f\u76f8\u540c\u3002<\/p>\n

\u6ce8\u610f\uff1a'+' \u8fd0\u7b97\u7b26\u4e0d\u4f1a\u8fde\u63a5\u5b57\u7b26\u4e32\u4e86\uff0c\u4ed6\u53ea\u7528\u4e8e\u52a0\u6cd5\u8fd0\u7b97\u3002<\/p>\n

EL\u5173\u7cfb\u8fd0\u7b97\u7b26\u6709\u4ee5\u4e0b\u516d\u4e2a\u8fd0\u7b97\u7b26<\/p>\n

\u5173\u7cfb\u8fd0\u7b97\u7b26\u00a0\u00a0\u00a0\u00a0\u00a0 \u8bf4\u660e\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u8303\u4f8b\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u7ed3\u679c
\n= = \u6216 eq\u00a0\u00a0 |\u00a0\u00a0\u00a0 \u7b49\u4e8e\u00a0\u00a0 |${ 5 = = 5 } \u6216 ${ 5 eq 5 } | true
\n!= \u6216 ne\u00a0\u00a0\u00a0 |\u00a0\u00a0 \u4e0d\u7b49\u4e8e |${ 5 != 5 } \u6216 ${ 5 ne 5 } | false
\n< \u6216 lt\u00a0\u00a0\u00a0\u00a0 |\u00a0\u00a0 \u5c0f\u4e8e\u00a0\u00a0\u00a0 |${ 3 < 5 }\u6216 ${ 3 lt 5 }\u00a0\u00a0\u00a0 | true
\n> \u6216 gt\u00a0\u00a0\u00a0\u00a0 |\u00a0\u00a0 \u5927\u4e8e\u00a0\u00a0\u00a0 |${ 3 > 5 }\u6216 ${ 3 gt 5 }\u00a0\u00a0\u00a0 | false
\n<= \u6216 le\u00a0\u00a0\u00a0 | \u5c0f\u4e8e\u7b49\u4e8e |${ 3 <= 5 }\u6216 ${ 3 le 5 }\u00a0\u00a0 | true
\n>= \u6216 ge\u00a0\u00a0\u00a0 | \u5927\u4e8e\u7b49\u4e8e |${ 3 >= 5 }\u6216 ${ 3 ge 5 }\u00a0\u00a0 | false<\/p>\n<\/div>\n

\n

5\u3001\u96c6\u5408\u8bbf\u95ee<\/strong><\/h3>\n<\/div>\n
\u6570\u7ec4\u8bbf\u95ee<\/div>\n

${}\u00a0\u00a0\u00a0\/\/\u5982request.getAttribute(\u201cname\u201d);<\/p>\n

List\u8bbf\u95ee<\/div>\n
Map\u8bbf\u95ee<\/div>\n<\/div>\n
\n

6\u3001\u9690\u5f0f\u5bf9\u8c61<\/h3>\n

JSP \u8868\u8fbe\u5f0f\u8bed\u8a00\u5b9a\u4e49\u4e86\u4e00\u7ec4\u9690\u5f0f\u5bf9\u8c61\uff0c\u5176\u4e2d\u8bb8\u591a\u5bf9\u8c61\u5728 JSP scriplet \u548c\u8868\u8fbe\u5f0f\u4e2d\u53ef\u7528\uff1a<\/p>\n

\"\"<\/a><\/p>\n<\/div>\n

<\/div>\n
\n

\u5141\u8bb8\u5bf9\u4ee5\u4e0b\u5bf9\u8c61\u8fdb\u884c\u7b80\u6613\u8bbf\u95ee\uff1a<\/p>\n

\n\n\n\n\n\n\n\n\n\n
\u672f\u8bed<\/th>\n\u5b9a\u4e49<\/th>\n<\/tr>\n
\n

param<\/p>\n<\/td>\n

\n

\u5c06\u8bf7\u6c42\u53c2\u6570\u540d\u79f0\u6620\u5c04\u5230\u5355\u4e2a\u5b57\u7b26\u4e32\u53c2\u6570\u503c\uff08\u901a\u8fc7\u8c03\u7528 ServletRequest.getParameter (String name) \u83b7\u5f97\uff09\u3002getParameter (String) \u65b9\u6cd5\u8fd4\u56de\u5e26\u6709\u7279\u5b9a\u540d\u79f0\u7684\u53c2\u6570\u3002\u8868\u8fbe\u5f0f $(param.name) \u76f8\u5f53\u4e8e request.getParameter (name)\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

paramValues<\/p>\n<\/td>\n

\n

\u5c06\u8bf7\u6c42\u53c2\u6570\u540d\u79f0\u6620\u5c04\u5230\u4e00\u4e2a\u6570\u503c\u6570\u7ec4\uff08\u901a\u8fc7\u8c03\u7528 ServletRequest.getParameter (String name) \u83b7\u5f97\uff09\u3002\u5b83\u4e0e param \u9690\u5f0f\u5bf9\u8c61\u975e\u5e38\u7c7b\u4f3c\uff0c\u4f46\u5b83\u68c0\u7d22\u4e00\u4e2a\u5b57\u7b26\u4e32\u6570\u7ec4\u800c\u4e0d\u662f\u5355\u4e2a\u503c\u3002\u8868\u8fbe\u5f0f ${paramvalues.name) \u76f8\u5f53\u4e8e request.getParamterValues(name)\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

header<\/p>\n<\/td>\n

\n

\u5c06\u8bf7\u6c42\u5934\u540d\u79f0\u6620\u5c04\u5230\u5355\u4e2a\u5b57\u7b26\u4e32\u5934\u503c\uff08\u901a\u8fc7\u8c03\u7528 ServletRequest.getHeader(String name) \u83b7\u5f97\uff09\u3002\u8868\u8fbe\u5f0f ${header.name} \u76f8\u5f53\u4e8e request.getHeader(name)\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

headerValues<\/p>\n<\/td>\n

\n

\u5c06\u8bf7\u6c42\u5934\u540d\u79f0\u6620\u5c04\u5230\u4e00\u4e2a\u6570\u503c\u6570\u7ec4\uff08\u901a\u8fc7\u8c03\u7528 ServletRequest.getHeaders(String) \u83b7\u5f97\uff09\u3002\u5b83\u4e0e\u5934\u9690\u5f0f\u5bf9\u8c61\u975e\u5e38\u7c7b\u4f3c\u3002\u8868\u8fbe\u5f0f ${headerValues.name} \u76f8\u5f53\u4e8e request.getHeaderValues(name)\u3002<\/p>\n<\/td>\n<\/tr>\n

cookie<\/td>\n\u5c06 cookie \u540d\u79f0\u6620\u5c04\u5230\u5355\u4e2a cookie \u5bf9\u8c61\u3002\u5411\u670d\u52a1\u5668\u53d1\u51fa\u7684\u5ba2\u6237\u7aef\u8bf7\u6c42\u53ef\u4ee5\u83b7\u5f97\u4e00\u4e2a\u6216\u591a\u4e2a cookie\u3002\u8868\u8fbe\u5f0f ${cookie.name.value} \u8fd4\u56de\u5e26\u6709\u7279\u5b9a\u540d\u79f0\u7684\u7b2c\u4e00\u4e2a cookie \u503c\u3002\u5982\u679c\u8bf7\u6c42\u5305\u542b\u591a\u4e2a\u540c\u540d\u7684 cookie\uff0c\u5219\u5e94\u8be5\u4f7f\u7528 ${headerValues.name} \u8868\u8fbe\u5f0f\u3002<\/td>\n<\/tr>\n
initParam<\/td>\n\u5c06\u4e0a\u4e0b\u6587\u521d\u59cb\u5316\u53c2\u6570\u540d\u79f0\u6620\u5c04\u5230\u5355\u4e2a\u503c\uff08\u901a\u8fc7\u8c03\u7528 ServletContext.getInitparameter(String name) \u83b7\u5f97\uff09\u3002<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

\u9664\u4e86\u4e0a\u8ff0\u4e24\u79cd\u7c7b\u578b\u7684\u9690\u5f0f\u5bf9\u8c61\u4e4b\u5916\uff0c\u8fd8\u6709\u4e9b\u5bf9\u8c61\u5141\u8bb8\u8bbf\u95ee\u591a\u79cd\u8303\u56f4\u7684\u53d8\u91cf\uff0c\u5982 Web \u4e0a\u4e0b\u6587\u3001\u4f1a\u8bdd\u3001\u8bf7\u6c42\u3001\u9875\u9762\uff1a<\/p>\n\n\n\n\n\n\n\n
\u672f\u8bed<\/th>\n\u5b9a\u4e49<\/th>\n<\/tr>\n
\n

pageScope<\/p>\n<\/td>\n

\n

\u5c06\u9875\u9762\u8303\u56f4\u7684\u53d8\u91cf\u540d\u79f0\u6620\u5c04\u5230\u5176\u503c\u3002\u4f8b\u5982\uff0cEL \u8868\u8fbe\u5f0f\u53ef\u4ee5\u4f7f\u7528 ${pageScope.objectName} \u8bbf\u95ee\u4e00\u4e2a JSP \u4e2d\u9875\u9762\u8303\u56f4\u7684\u5bf9\u8c61\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 ${pageScope.objectName.attributeName} \u8bbf\u95ee\u5bf9\u8c61\u7684\u5c5e\u6027\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

requestScope<\/p>\n<\/td>\n

\n

\u5c06\u8bf7\u6c42\u8303\u56f4\u7684\u53d8\u91cf\u540d\u79f0\u6620\u5c04\u5230\u5176\u503c\u3002\u8be5\u5bf9\u8c61\u5141\u8bb8\u8bbf\u95ee\u8bf7\u6c42\u5bf9\u8c61\u7684\u5c5e\u6027\u3002\u4f8b\u5982\uff0cEL \u8868\u8fbe\u5f0f\u53ef\u4ee5\u4f7f\u7528 ${requestScope.objectName} \u8bbf\u95ee\u4e00\u4e2a JSP \u8bf7\u6c42\u8303\u56f4\u7684\u5bf9\u8c61\uff0c\u8fd8\u53ef\u4ee5\u4f7f\u7528 ${requestScope.objectName.attributeName} \u8bbf\u95ee\u5bf9\u8c61\u7684\u5c5e\u6027\u3002<\/p>\n<\/td>\n<\/tr>\n

\n

sessionScope<\/p>\n<\/td>\n

\n

\u5c06\u4f1a\u8bdd\u8303\u56f4\u7684\u53d8\u91cf\u540d\u79f0\u6620\u5c04\u5230\u5176\u503c\u3002\u8be5\u5bf9\u8c61\u5141\u8bb8\u8bbf\u95ee\u4f1a\u8bdd\u5bf9\u8c61\u7684\u5c5e\u6027\u3002\u4f8b\u5982\uff1a<\/p>\n

$sessionScope.name}<\/p>\n<\/td>\n<\/tr>\n

\n

applicationScope<\/p>\n<\/td>\n

\n

\u5c06\u5e94\u7528\u7a0b\u5e8f\u8303\u56f4\u7684\u53d8\u91cf\u540d\u79f0\u6620\u5c04\u5230\u5176\u503c\u3002\u8be5\u9690\u5f0f\u5bf9\u8c61\u5141\u8bb8\u8bbf\u95ee\u5e94\u7528\u7a0b\u5e8f\u8303\u56f4\u7684\u5bf9\u8c61<\/p>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n

\u00a0\u7279\u522b\u8bf4\u660e\uff1a<\/strong><\/p>\n

cookie\u5bf9\u8c61<\/strong><\/p>\n

\u6240\u8c13\u7684cookie\u662f\u4e00\u4e2a\u5c0f\u5c0f\u7684\u6587\u672c\u6587\u4ef6\uff0c\u5b83\u662f\u4ee5key\u3001value\u7684\u65b9\u5f0f\u5c06SessionTracking\u7684\u5185\u5bb9\u8bb0\u5f55\u5728\u8fd9\u4e2a\u6587\u672c\u6587\u4ef6\u5185\uff0c\u8fd9\u4e2a\u6587\u672c\u6587\u4ef6\u901a\u5e38\u5b58\u5728\u4e8e\u6d4f\u89c8\u5668\u7684\u6682\u5b58\u533a\u5185\u3002JSTL\u5e76\u6ca1\u6709\u63d0\u4f9b\u8bbe\u5b9acookie\u7684\u52a8\u4f5c\uff0c\u56e0\u4e3a\u8fd9\u4e2a\u52a8\u4f5c\u901a\u5e38\u90fd \u662f\u540e\u7aef\u5f00\u53d1\u8005\u5fc5\u987b\u53bb\u505a\u7684\u4e8b\u60c5\uff0c\u800c\u4e0d\u662f\u4ea4\u7ed9\u524d\u7aef\u7684\u5f00\u53d1\u8005\u3002\u5982\u679c\u6211\u4eec\u5728cookie\u4e2d\u8bbe\u5b9a\u4e00\u4e2a\u540d\u79f0\u4e3auserCountry\u7684\u503c\uff0c\u90a3\u4e48\u53ef\u4ee5\u4f7f \u7528${cookie.userCountry}\u6765\u53d6\u5f97\u5b83\u3002<\/p>\n

header\u548cheaderValues<\/strong>\uff08\u8bf7\u6c42\u62a5\u5934\u5bf9\u8c61\uff09<\/strong>
\nheader\u50a8\u5b58\u7528\u6237\u6d4f\u89c8\u5668\u548c\u670d\u52a1\u7aef\u7528\u6765\u6c9f\u901a\u7684\u6570\u636e\uff0c\u5f53\u7528\u6237\u8981\u6c42\u670d\u52a1\u7aef\u7684\u7f51\u9875\u65f6\uff0c\u4f1a\u9001\u51fa\u4e00\u4e2a\u8bb0\u8f7d\u8981\u6c42\u4fe1\u606f\u7684\u6807\u5934\u6587\u4ef6\uff0c\u4f8b\u5982\uff1a\u7528\u6237\u6d4f\u89c8\u5668\u7684\u7248\u672c\u3001\u7528\u6237\u8ba1\u7b97\u673a\u6240\u8bbe\u5b9a\u7684\u533a\u57df\u7b49\u5176\u4ed6\u76f8\u5173\u6570\u636e\u3002\u5982\u679c\u8981\u53d6\u5f97\u7528\u6237\u6d4f\u89c8\u5668\u7684\u7248\u672c\uff0c\u5373${header[\"User-Agent\"]}\u3002\u53e6\u5916\u5728\u5f88\u5c11\u673a\u4f1a\u4e0b\uff0c\u6709\u53ef\u80fd\u540c\u4e00\u6807\u5934\u540d\u79f0\u62e5\u6709\u4e0d\u540c\u7684\u503c\uff0c\u6b64\u65f6\u5fc5\u987b\u6539\u4e3a\u4f7f\u7528headerValues\u6765\u53d6\u5f97\u8fd9\u4e9b\u503c\u3002
\n\u6ce8\u610f\uff1a\u56e0\u4e3aUser-Agent\u4e2d\u5305\u542b\u201c-\u201d\u8fd9\u4e2a\u7279\u6b8a\u5b57\u7b26\uff0c\u6240\u4ee5\u5fc5\u987b\u4f7f\u7528\u201c[]\u201d\uff0c\u800c\u4e0d\u80fd\u5199\u6210${header.User-Agent}\u3002
\ninitParam
\n\u5c31\u50cf\u5176\u4ed6\u5c5e\u6027\u4e00\u6837\uff0c\u6211\u4eec\u53ef\u4ee5\u81ea\u884c\u8bbe\u5b9aweb\u5e94\u7528\u7684\u73af\u5883\u53c2\u6570(Context)\uff0c\u5f53\u6211\u4eec\u60f3\u53d6\u5f97\u8fd9\u4e9b\u53c2\u6570\u65f6\uff0c\u53ef\u4ee5\u4f7f\u7528initParam\u9690\u542b\u5bf9\u8c61\u53bb\u53d6\u5f97\u5b83\uff0c\u4f8b\u5982\uff1a\u5f53\u6211\u4eec\u5728web.xml\u4e2d\u8bbe\u5b9a\u5982\u4e0b\uff1a<\/p>\n

<?xml version=\"1.0\" encoding=\"ISO-8859-1\"?>
\n<web-app xmlns=\"http:\/\/java.sun.com\/xml\/ns\/j2ee\"
\nxmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"
\nxsi:schemaLocation=\"http:\/\/java.sun.com\/xml\/ns\/j2ee\/web-app_2_4.xsd\"
\nversion=\"2.4\">
\n<context-param>
\n<param-name>userid<\/param-name>
\n<param-value>mike<\/param-value>
\n<\/context-param>
\n<\/web-app>
\n\u90a3\u4e48\u6211\u4eec\u5c31\u53ef\u4ee5\u76f4\u63a5\u4f7f\u7528 ${initParam.userid}\u6765\u53d6\u5f97\u540d\u79f0\u4e3auserid\uff0c\u5176\u503c\u4e3amike\u7684\u53c2\u6570\u3002\u4e0b\u9762\u662f\u4e4b\u524d\u7684\u505a\u6cd5\uff1aString userid =(String)application.getInitParameter(\"userid\");<\/p>\n

pageContext\u5bf9\u8c61<\/strong><\/p>\n

\u6211\u4eec\u53ef\u4ee5\u4f7f\u7528 ${pageContext}\u6765\u53d6\u5f97\u5176\u4ed6\u6709\u5173\u7528\u6237\u8981\u6c42\u6216\u9875\u9762\u7684\u8be6\u7ec6\u4fe1\u606f\u3002\u4e0b\u9762\u5217\u51fa\u4e86\u51e0\u4e2a\u6bd4\u8f83\u5e38\u7528\u7684\u90e8\u5206\u3002
\nExpression \u8bf4 \u660e
\n${pageContext.request} |\u53d6\u5f97\u8bf7\u6c42\u5bf9\u8c61
\n${pageContext.session} |\u53d6\u5f97session\u5bf9\u8c61
\n${pageContext.request.queryString} |\u53d6\u5f97\u8bf7\u6c42\u7684\u53c2\u6570\u5b57\u7b26\u4e32
\n${pageContext.request.requestURL} |\u53d6\u5f97\u8bf7\u6c42\u7684URL\uff0c\u4f46\u4e0d\u5305\u62ec\u8bf7\u6c42\u4e4b\u53c2\u6570\u5b57\u7b26\u4e32
\n${pageContext.request.contextPath} |\u670d\u52a1\u7684web application\u7684\u540d\u79f0
\n${pageContext.request.method} |\u53d6\u5f97HTTP\u7684\u65b9\u6cd5(GET\u3001POST)
\n${pageContext.request.protocol} |\u53d6\u5f97\u4f7f\u7528\u7684\u534f\u8bae(HTTP\/1.1\u3001HTTP\/1.0)
\n${pageContext.request.remoteUser} |\u53d6\u5f97\u7528\u6237\u540d\u79f0
\n${pageContext.request.remoteAddr } |\u53d6\u5f97\u7528\u6237\u7684IP\u5730\u5740
\n${pageContext.session.new} |\u5224\u65adsession\u662f\u5426\u4e3a\u65b0\u7684\uff0c\u6240\u8c13\u65b0\u7684session\uff0c\u8868\u793a\u521a\u7531 server\u4ea7\u751f\u800cclient\u5c1a\u672a\u4f7f\u7528
\n${pageContext.session.id} |\u53d6\u5f97session\u7684ID
\n${pageContext.servletContext.serverInfo}|\u53d6\u5f97\u4e3b\u673a\u7aef\u7684\u670d\u52a1\u4fe1\u606f<\/p>\n

7\u3001\u7279\u522b\u5f3a\u8c03<\/h3>\n

1\u3001\u6ce8\u610f\u5f53\u8868\u8fbe\u5f0f\u6839\u636e\u540d\u79f0\u5f15\u7528\u8fd9\u4e9b\u5bf9\u8c61\u4e4b\u4e00\u65f6\uff0c\u8fd4\u56de\u7684\u662f\u76f8\u5e94\u7684\u5bf9\u8c61\u800c\u4e0d\u662f\u76f8\u5e94\u7684\u5c5e\u6027\u3002\u4f8b\u5982\uff1a\u5373\u4f7f\u73b0\u6709\u7684 pageContext \u5c5e\u6027\u5305\u542b\u67d0\u4e9b\u5176\u4ed6\u503c\uff0c${pageContext} \u4e5f\u8fd4\u56de PageContext \u5bf9\u8c61\u3002<\/p>\n

2\u3001 \u6ce8\u610f <%@ pageisELIgnored=\"true\" %> \u8868\u793a\u662f\u5426\u7981\u7528EL\u8bed\u8a00,TRUE\u8868\u793a\u7981\u6b62.FALSE\u8868\u793a\u4e0d\u7981\u6b62.JSP2.0\u4e2d\u9ed8\u8ba4\u7684\u542f\u7528EL\u8bed\u8a00\u3002<\/p>\n<\/div>\n

<\/div>\n
<\/div>\n
<\/div>\n
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..<\/div>\n
<\/div>\n","protected":false},"excerpt":{"rendered":"

1\u3001\u4ec0\u4e48\u662fEL \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 EL\u662fJSP\u8868\u8fbe\u5f0f\u8bed\u8a00\uff0c\u5168\u79f0\u662fExpressio … \u7ee7\u7eed\u9605\u8bfb →<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[336],"tags":[],"class_list":["post-1406","post","type-post","status-publish","format-standard","hentry","category-jsp"],"_links":{"self":[{"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/posts\/1406","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/comments?post=1406"}],"version-history":[{"count":0,"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/posts\/1406\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/media?parent=1406"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/categories?post=1406"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xiaobo.li\/notes\/wp-json\/wp\/v2\/tags?post=1406"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}