The <jsp:param> action is used to provide information in the form of key/value pair. This action can be used as direct child element of the following actions: <jsp:include>, <jsp:forward> and <jsp:params> (which is a child element of the <jsp:plugin> action). The JSP compiler will issue a translation error if this element is used elsewhere.
The <jsp:param> action has pretty simple and straightforward syntax:
<jsp:param name="paramName" value="paramValue" />
Both of the attributes paramNameand paramValue are mandatory, and the paramValue can accept a runtime expression.
For the <jsp:include> and <jsp:forward>actions, the parameters will be added to the request object of the included page and forwarded page.
<jsp:include page="header.jsp" > <jsp:param name="language" value="english" /> <jsp:param name="country" value="USA" /> </jsp:include>
Language: ${param.language} Country: ${param.country}
<jsp:forward page="login.jsp" /> <jsp:param name="username" value="Tom"/> </jsp:forward>
Username: ${param.username}
<jsp:plugin type="applet" code="net.codejava.applet.MyApplet.class" codebase="html"> <jsp:params> <jsp:param name="username" value="Tom" /> </jsp:params> </jsp:plugin>
Access the parameters in the applet:
String username = getParameter("username");