Spring 小计

FilterInvocationMetadataSource

public class FilterInvocationSecurityMetadataSourceImpl implements
		FilterInvocationSecurityMetadataSource {

	private final Logger logger = LoggerFactory.getLogger(getClass());

	// 默认使用AntUrlPathMatcher
	private UrlMatcher urlMatcher;

	private boolean stripQueryStringFromUrls;

	private static final Set<String> HTTP_METHODS = new HashSet<String>(
			Arrays.asList("DELETE", "GET", "HEAD", "OPTIONS", "POST", "PUT",
					"TRACE"));

	/**
	 * Stores request maps keyed by specific HTTP methods. A null key matches
	 * any method
	 */
	private Map<String, Map<Object, Collection<ConfigAttribute>>> httpMethodMap = new HashMap<String, Map<Object, Collection<ConfigAttribute>>>();

	@Autowired
	public FilterInvocationSecurityMetadataSourceImpl(
			SecurityMetadataConverter adapter) {
		urlMatcher = new AntUrlPathMatcher();

//		LinkedHashMap<RequestKey, Collection<ConfigAttribute>> requestMap = adapter.getRequestMap();
//		for (Map.Entry<RequestKey, Collection<ConfigAttribute>> entry : requestMap
//				.entrySet()) {
//			addSecureUrl(entry.getKey().getUrl(), entry.getKey().getMethod(),
//					entry.getValue());
//		}
		Collection<Config> configs = adapter.configs();
		for(Config config:configs){
			//logger.info("{}",config.getAttributes());
			addSecureUrl(config.getPath(),null,config.getAttributes());
		}
	}

	// ~ Methods
	// ========================================================================================================

	/**
	 * Adds a URL,attribute-list pair to the request map, first allowing the
	 * <tt>UrlMatcher</tt> to process the pattern if required, using its
	 * <tt>compile</tt> method. The returned object will be used as the key to
	 * the request map and will be passed back to the <tt>UrlMatcher</tt> when
	 * iterating through the map to find a match for a particular URL.
	 */
	private void addSecureUrl(String pattern, String method,
			Collection<ConfigAttribute> attrs) {
		//
		Map<Object, Collection<ConfigAttribute>> mapToUse = getRequestMapForHttpMethod(method);

		mapToUse.put(urlMatcher.compile(pattern), attrs);
		//attrs.toArray(new ConfigAttribute[] {})[0].getAttribute();
		if (logger.isDebugEnabled()) {
			logger.debug("Added URL pattern: "
					+ pattern
					+ "; attributes: "
					+ attrs
					+ (method == null ? "" : " for HTTP method '" + method
							+ "'"));
		}
	}

	/**
	 * Return the HTTP method specific request map, creating it if it doesn't
	 * already exist.
	 * 
	 * @param method
	 *            GET, POST etc
	 * @return map of URL patterns to <tt>ConfigAttribute</tt>s for this method.
	 */
	private Map<Object, Collection<ConfigAttribute>> getRequestMapForHttpMethod(
			String method) {
		if (method != null && !HTTP_METHODS.contains(method)) {
			throw new IllegalArgumentException("Unrecognised HTTP method: '"
					+ method + "'");
		}

		// 用Http Method当作key,value是一个Http Url 
		Map<Object, Collection<ConfigAttribute>> methodRequestMap = httpMethodMap
				.get(method);

		if (methodRequestMap == null) {
			methodRequestMap = new LinkedHashMap<Object, Collection<ConfigAttribute>>();
			httpMethodMap.put(method, methodRequestMap);
		}

		return methodRequestMap;
	}

	public Collection<ConfigAttribute> getAllConfigAttributes() {
		Set<ConfigAttribute> allAttributes = new HashSet<ConfigAttribute>();

		for (Map.Entry<String, Map<Object, Collection<ConfigAttribute>>> entry : httpMethodMap
				.entrySet()) {
			for (Collection<ConfigAttribute> attrs : entry.getValue().values()) {
				allAttributes.addAll(attrs);
			}
		}

		return allAttributes;
	}

	public Collection<ConfigAttribute> getAttributes(Object object) {
		if ((object == null) || !this.supports(object.getClass())) {
			throw new IllegalArgumentException(
					"Object must be a FilterInvocation");
		}

		String url = ((FilterInvocation) object).getRequestUrl();
		String method = ((FilterInvocation) object).getHttpRequest()
				.getMethod();

		return lookupAttributes(url, method);
	}

	/**
	 * Performs the actual lookup of the relevant <tt>ConfigAttribute</tt>s for
	 * the given <code>FilterInvocation</code>.
	 * <p>
	 * By default, iterates through the stored URL map and calls the
	 * {@link UrlMatcher#pathMatchesUrl(Object path, String url)} method until a
	 * match is found.
	 * 
	 * @param url
	 *            the URI to retrieve configuration attributes for
	 * @param method
	 *            the HTTP method (GET, POST, DELETE...), or null for any
	 *            method.
	 * 
	 * @return the <code>ConfigAttribute</code>s that apply to the specified
	 *         <code>FilterInvocation</code> or null if no match is found
	 */
	public final Collection<ConfigAttribute> lookupAttributes(String url,
			String method) {
		if (stripQueryStringFromUrls) {
			// Strip anything after a question mark symbol, as per SEC-161. See
			// also SEC-321
			int firstQuestionMarkIndex = url.indexOf("?");

			if (firstQuestionMarkIndex != -1) {
				url = url.substring(0, firstQuestionMarkIndex);
			}
		}

		if (urlMatcher.requiresLowerCaseUrl()) {
			url = url.toLowerCase();

			if (logger.isDebugEnabled()) {
				logger.debug("Converted URL to lowercase, from: '" + url
						+ "'; to: '" + url + "'");
			}
		}

		// Obtain the map of request patterns to attributes for this method and
		// lookup the url.
		Collection<ConfigAttribute> attributes = extractMatchingAttributes(url,
				httpMethodMap.get(method));

		// If no attributes found in method-specific map, use the general one
		// stored under the null key
		if (attributes == null) {
			attributes = extractMatchingAttributes(url, httpMethodMap.get(null));
		}

		return attributes;
	}

	private Collection<ConfigAttribute> extractMatchingAttributes(String url,
			Map<Object, Collection<ConfigAttribute>> map) {
		if (map == null) {
			return null;
		}

		final boolean debug = logger.isDebugEnabled();

		for (Map.Entry<Object, Collection<ConfigAttribute>> entry : map
				.entrySet()) {
			Object p = entry.getKey();
			boolean matched = urlMatcher.pathMatchesUrl(entry.getKey(), url);

			if (debug) {
				logger.debug("Candidate is: '" + url + "'; pattern is " + p
						+ "; matched=" + matched);
			}

			if (matched) {
				return entry.getValue();
			}
		}
		return null;
	}

	public boolean supports(Class<?> clazz) {
		return FilterInvocation.class.isAssignableFrom(clazz);
	}

	protected UrlMatcher getUrlMatcher() {
		return urlMatcher;
	}

	public boolean isConvertUrlToLowercaseBeforeComparison() {
		return urlMatcher.requiresLowerCaseUrl();
	}

	public void setStripQueryStringFromUrls(boolean stripQueryStringFromUrls) {
		this.stripQueryStringFromUrls = stripQueryStringFromUrls;
	}
}