package org.springframework.web.servlet.theme;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.util.WebUtils;
/**
* Implementation of ThemeResolver that uses a cookie sent back to the user
* in case of a custom setting, with a fallback to the fixed locale.
* This is especially useful for stateless applications without user sessions.
*
* <p>Custom controllers can thus override the user's theme by calling setTheme,
* e.g. responding to a certain theme change request.
*
* @author Jean-Pierre Pawlak
* @author Juergen Hoeller
* @since 17.06.2003
*/
public class CookieThemeResolver extends AbstractThemeResolver {
/**
* Name of the request attribute that holds the theme name. Only used
* for overriding a cookie value if the theme has been changed in the
* course of the current request! Use RequestContext.getTheme() to
* retrieve the current theme in controllers or views.
* @see org.springframework.web.servlet.support.RequestContext#getTheme
*/
public static final String THEME_REQUEST_ATTRIBUTE_NAME = CookieThemeResolver.class.getName() + ".THEME";
public static final String DEFAULT_COOKIE_NAME = CookieThemeResolver.class.getName() + ".THEME";
public static final String DEFAULT_COOKIE_PATH = "/";
public static final int DEFAULT_COOKIE_MAX_AGE = Integer.MAX_VALUE;
private String cookieName = DEFAULT_COOKIE_NAME;
private int cookieMaxAge = DEFAULT_COOKIE_MAX_AGE;
private String cookiePath = DEFAULT_COOKIE_PATH;
/**
* Use the given name for theme cookies, containing the theme name.
*/
public void setCookieName(String cookieName) {
this.cookieName = cookieName;
}
public String getCookieName() {
return cookieName;
}
/**
* Use the given path for theme cookies.
* The cookie is only visible for URLs in the path and below.
*/
public String getCookiePath() {
return cookiePath;
}
public void setCookiePath(String cookiePath) {
this.cookiePath = cookiePath;
}
/**
* Use the given maximum age, specified in seconds, for locale cookies.
* Useful special value: -1 ... not persistent, deleted when client shuts down
*/
public void setCookieMaxAge(int cookieMaxAge) {
this.cookieMaxAge = cookieMaxAge;
}
public int getCookieMaxAge() {
return cookieMaxAge;
}
public String resolveThemeName(HttpServletRequest request) {
// check theme for preparsed resp. preset theme
String theme = (String) request.getAttribute(THEME_REQUEST_ATTRIBUTE_NAME);
if (theme != null)
return theme;
// retrieve cookie value
Cookie cookie = WebUtils.getCookie(request, getCookieName());
if (cookie != null) {
return cookie.getValue();
}
// fallback
return getDefaultThemeName();
}
public void setThemeName(HttpServletRequest request, HttpServletResponse response, String themeName) {
Cookie cookie = null;
if (themeName != null) {
// set request attribute and add cookie
request.setAttribute(THEME_REQUEST_ATTRIBUTE_NAME, themeName);
cookie = new Cookie(getCookieName(), themeName);
cookie.setMaxAge(getCookieMaxAge());
cookie.setPath(cookiePath);
}
else {
// set request attribute to fallback theme and remove cookie
request.setAttribute(THEME_REQUEST_ATTRIBUTE_NAME, getDefaultThemeName());
cookie = new Cookie(getCookieName(), "");
cookie.setMaxAge(0);
cookie.setPath(cookiePath);
}
response.addCookie(cookie);
}
}