package jodd.servlet.tags.imports;
import java.io.IOException;
import java.util.ArrayList;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.tagext.TagSupport;
/**
* Includes local resource into the current page and organize templates. It
* can be used for including local content into the current page.
*
* Import tag can be used for managing web templates, macros or tiles,
* however it is called. There are 2 different types of usage:
*
*
*
* Without template page. In this case every must have import for each
* part of the page that will be loaded. When it is repeated on many pages,
* this may become hard to maintain.
*
*
* With templates. In this case, template is specified in an external jsp
* file that is imported in every page that will use that template. By using
* import parameters it is possible to manage included content.
*
*
*
* Import tag is about 2x faster then default jsp:include (tomcat v5.)
*
*/
public class Import extends TagSupport {
private static String SERVLET_PATH = "jodd.servlet.tags.include.servlet_path";
private boolean isPageRelative;
private String page = "";
public void setPage(String v) {
page = v;
isPageRelative = (page.startsWith("/") == false);
}
protected String getPage() {
return page;
}
private ArrayList attrs;
public void addAttributeName(String s) {
attrs.add(s);
}
/**
* Evaluate tag content.
*
* @return EVAL_BODY_INCLUDE
*/
public int doStartTag() {
attrs = new ArrayList();
return EVAL_BODY_AGAIN;
}
/**
* Finds and renders imported resource. A resource (page) can be specified
* relatively (when it doesn't start with a slash) or absolutely from the
* application root (when it starts with the slash).
*
* This method will be called after tag process any existing param
* parameters.
*
* @return EVAL_PAGE
*/
public int doEndTag() {
HttpServletRequest request = (HttpServletRequest)pageContext.getRequest();
try {
RequestDispatcher rd = null;
boolean first = false; // indicates topmost servlet
String sp = "";
String targetUrl = new String(page);
if (isPageRelative == true) {
sp = (String) request.getAttribute(SERVLET_PATH);
if (sp == null) {
first = true;
sp = request.getServletPath();
sp = sp.substring(0, sp.lastIndexOf('/'));
}
targetUrl = sp + '/' + page;
}
rd = request.getRequestDispatcher(targetUrl);
ImportResponseWrapper irw = new ImportResponseWrapper(pageContext.getResponse(), pageContext.getOut());
String previous_sp = sp;
sp = targetUrl.substring(0, targetUrl.lastIndexOf('/'));
request.setAttribute(SERVLET_PATH, sp);
rd.include(request, irw);
if (first == true) {
request.removeAttribute(SERVLET_PATH);
} else {
request.setAttribute(SERVLET_PATH, previous_sp);
}
} catch (IOException ioe) {
} catch (ServletException sex) {
}
// end of the page, remove not persistent params....
for (int i = 0; i < attrs.size(); i++) {
request.removeAttribute((String)attrs.get(i));
}
return EVAL_PAGE;
}
}
