1) VARIAVEIS DE URL

1.1) Como jsp
<h3>Pegando URL/Path/File via JSP</h3>
<%
	String Url = request.getRequestURL().toString();
	String Uri = request.getRequestURI().toString();
	String Url_Uri = request.getRequestURL().toString().replace(request.getRequestURI(), "");
	String serverPath = request.getServletPath().toString();
	String serverName = "http://" + request.getServerName();
%>
<ul>
	<li><strong>Url:</strong><br /><%=Url%></li>
	<li><strong>Uri:</strong><br /><%=Uri%></li>
	<li><strong>Url - Uri:</strong><br /><%=Url_Uri%></li>
	<li><strong>Server Path:</strong><br /><%=serverPath%></li>
	<li><strong>Server Name:</strong><br /><%=serverName%></li>
</ul>

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1.2) Como OpenCms Notation
<h3>Pegando URL/Path/File via OpenCms Notation</h3>
<ul>
	<li><strong>Url:</strong><br /><cms:info property="opencms.url" /></li>
	<li><strong>Uri:</strong><br /><cms:info property="opencms.uri" /></li>
	<li><strong>Uri Request:</strong><br /><cms:info property="opencms.request.uri" /></li>
	<li><strong>Uri Element:</strong><br /><cms:info property="opencms.request.element.uri" /></li>
	<li><strong>Version:</strong><br /><cms:info property="opencms.version" /></li>
	<li><strong>Webapp:</strong><br /><cms:info property="opencms.webapp" /></li>
	<li><strong>Webapp Path:</strong><br /><cms:info property="opencms.webbasepath" /></li>
	<li><strong>Folder:</strong><br /><cms:info property="opencms.request.folder" /></li>
	<li><strong>Enconding:</strong><br /><cms:info property="opencms.request.encoding" /></li>
	<li><strong>Locale:</strong><br /><cms:info property="opencms.request.locale" /></li>
	<li><strong>User Dir:</strong><br /><cms:info property="user.dir" /></li>
</ul>

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2) PEGANDO PARAMETROS DE URL

2.1.a) Pegar 1 parametro e armazenar numa variavel jsp:
<% String myVar = request.getParameter("meuParam"); %>

PS: Pegar parametro sem criar variavel jsp:
<%=pageContext.getAttribute("meuParam").toString()%>

2.1.b) Pegar par‰metro e armazenar numa variavel jsp com valor default, caso nulo
String myVar = request.getParameter("meuParam") != null ? request.getParameter("meuParam") : "0";

2.1.c) Pegar 1 parametro e armazenar numa variavel cset e, em seguida, passa-la para vari‡vel jsp:
<c:set var=ÒmeuSetÓ value="${param.meuParam}"/>
String myVar = pageContext.getAttribute("meuSet").toString() != null ? pageContext.getAttribute("meuSet").toString() : "0";

2.1.d) Pegar todos os parametros e armazenar numa variavel:
String myVar = "";
<%if(request.getQueryString() != null) {
	myVar = request.getQueryString();
}%>

2.2) imprimir variavel
<%=myVar%> ou <% out.print(myVar); %>

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3) ACRESCENTAR PARAMETROS NA URL

<%
String Link = "http:www.google.com.br";
String LinkConvertido;
if (Link.indexOf('?') != -1) {
	LinkConvertido = Link + "&param=Valor";
}else{
	LinkConvertido = Link + "?param=Valor";
}
out.print(LinkConvertido);
%>

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4) METODO DEFINITIVO PARA PEGAR URL COMPLETA (URL + PARAMETROS):

4.1) Como OpenCms Notation:

http://<%=request.getServerName()%>
+ Url:
<cms:info property="opencms.request.uri" />
ou <cms:link><cms:info property='opencms.request.uri'/></cms:link>
+ Parametros:
<%if(request.getQueryString() != null) { out.print(request.getQueryString()); }%>


4.2) Como JSP:
<c:set var="UrlRequest"><cms:info property="opencms.request.uri" /></c:set>
<%
String UrlServerName = "http://"+request.getServerName();
String UrlRequest = UrlServerName + pageContext.getAttribute("UrlRequest").toString();
String UrlComplete = UrlRequest;
if(request.getQueryString() != null) {
	UrlComplete += "?"+request.getQueryString();
}
out.print(UrlComplete);
%>

4.3) Como JSTL:
<%-- File Path: ${pageContext.request} or ${pageContext.request.contextPath} or ${pageContext.request.requestURI}--%>
<%-- Method: ${pageContext.request.method} --%>
<%-- Fonte: http://www.java2s.com/Tutorial/Java/0380__JSTL/GetHTTPRequestbyusingJSTL.htm --%>
<c:set var="UrlProtocol" value="${pageContext.request.secure == true ? 'https' : 'http'}" />
<c:set var="UrlRequest">${UrlProtocol}://${pageContext.request.serverName}${pageContext.request.pathInfo}</c:set>
<c:if test="${pageContext.request.queryString != null}">
	<c:set var="UrlRequest" value="${UrlRequest}?${pageContext.request.queryString}" />
</c:if>
URL Completa: ${UrlRequest}