JSP取得内置对象

<hr>-----request.getAttributeNames---------<hr>
<%{ 
Enumeration<String> attrEnum =request.getAttributeNames();
String attrName = null;
while (attrEnum.hasMoreElements() ) {
	attrName = attrEnum.nextElement();
	out.println( attrName + ":");
    out.println( request.getAttribute(attrName) + "<br>");
}
}
%>
<hr>------request.getParameterNames---------<hr>
<%
{ 
Enumeration<String> attrEnum =request.getParameterNames();
String attrName = null;
while (attrEnum.hasMoreElements() ) {
	attrName = attrEnum.nextElement();
	out.println( attrName + ":");
    out.println( request.getParameter(attrName) + "<br>");
}
}
%>
<hr>-----request.getHeaderNames----------<hr>
<%{ 
Enumeration<String> attrEnum =request.getHeaderNames();
String attrName = null;
while (attrEnum.hasMoreElements() ) {
	attrName = attrEnum.nextElement();
	out.println( attrName + ":");
    out.println( request.getHeader(attrName) + "<br>");
}
}
%>
<hr>-------session.getAttributeNames--------<hr>
<%{ 
Enumeration<String> attrEnum =session.getAttributeNames();
String attrName = null;
while (attrEnum.hasMoreElements() ) {
	attrName = attrEnum.nextElement();
	out.println( attrName + ":");
    out.println( session.getAttribute(attrName) + "<br>");
}
}
%>