Remove ResourceServlet (deprecated in 4.3)

9 years ago · 9bcc7c3b06
1 changed files with 0 additions and 347 deletions
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/ResourceServlet.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/ResourceServlet.java
@ -1,347 +0,0 @@
 /*
 * Copyright 2002-2016 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
 package org.springframework.web.servlet;
 import java.io.IOException;
 import javax.servlet.RequestDispatcher;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
 import javax.servlet.http.HttpServletResponse;
 import org.springframework.util.AntPathMatcher;
 import org.springframework.util.PathMatcher;
 import org.springframework.util.StringUtils;
 import org.springframework.web.context.support.ServletContextResource;
 /**
 * Simple servlet that can expose an internal resource, including a
 * default URL if the specified resource is not found. An alternative,
 * for example, to trying and catching exceptions when using JSP include.
 *
 * <p>A further usage of this servlet is the ability to apply last-modified
 * timestamps to quasi-static resources (typically JSPs). This can happen
 * as bridge to parameter-specified resources, or as proxy for a specific
 * target resource (or a list of specific target resources to combine).
 *
 * <p>A typical usage would map a URL like "/ResourceServlet" onto an instance
 * of this servlet, and use the "JSP include" action to include this URL,
 * with the "resource" parameter indicating the actual target path in the WAR.
 *
 * <p>The {@code defaultUrl} property can be set to the internal
 * resource path of a default URL, to be rendered when the target resource
 * is not found or not specified in the first place.
 *
 * <p>The "resource" parameter and the {@code defaultUrl} property can
 * also specify a list of target resources to combine. Those resources will be
 * included one by one to build the response. If last-modified determination
 * is active, the newest timestamp among those files will be used.
 *
 * <p>The {@code allowedResources} property can be set to a URL
 * pattern of resources that should be available via this servlet.
 * If not set, any target resource can be requested, including resources
 * in the WEB-INF directory!
 *
 * <p>If using this servlet for direct access rather than via includes,
 * the {@code contentType} property should be specified to apply a
 * proper content type. Note that a content type header in the target JSP will
 * be ignored when including the resource via a RequestDispatcher include.
 *
 * <p>To apply last-modified timestamps for the target resource, set the
 * {@code applyLastModified} property to true. This servlet will then
 * return the file timestamp of the target resource as last-modified value,
 * falling back to the startup time of this servlet if not retrievable.
 *
 * <p>Note that applying the last-modified timestamp in the above fashion
 * just makes sense if the target resource does not generate content that
 * depends on the HttpSession or cookies; it is just allowed to evaluate
 * request parameters.
 *
 * <p>A typical case for such last-modified usage is a JSP that just makes
 * minimal usage of basic means like includes or message resolution to
 * build quasi-static content. Regenerating such content on every request
 * is unnecessary; it can be cached as long as the file hasn't changed.
 *
 * <p>Note that this servlet will apply the last-modified timestamp if you
 * tell it to do so: It's your decision whether the content of the target
 * resource can be cached in such a fashion. Typical use cases are helper
 * resources that are not fronted by a controller, like JavaScript files
 * that are generated by a JSP (without depending on the HttpSession).
 *
 * @author Juergen Hoeller
 * @author Rod Johnson
 * @see #setDefaultUrl
 * @see #setAllowedResources
 * @see #setApplyLastModified
 */
@SuppressWarnings("serial")
 public class ResourceServlet extends HttpServletBean {
 	/**
 	 * Any number of these characters are considered delimiters
 	 * between multiple resource paths in a single String value.
 	 */
 	public static final String RESOURCE_URL_DELIMITERS = ",; \t\n";
 	/**
 	 * Name of the parameter that must contain the actual resource path.
 	 */
 	public static final String RESOURCE_PARAM_NAME = "resource";
 	private String defaultUrl;
 	private String allowedResources;
 	private String contentType;
 	private boolean applyLastModified = false;
 	private PathMatcher pathMatcher;
 	private long startupTime;
 	/**
 	 * Set the URL within the current web application from which to
 	 * include content if the requested path isn't found, or if none
 	 * is specified in the first place.
 	 * <p>If specifying multiple URLs, they will be included one by one
 	 * to build the response. If last-modified determination is active,
 	 * the newest timestamp among those files will be used.
 	 * @see #setApplyLastModified
 	 */
 	public void setDefaultUrl(String defaultUrl) {
 		this.defaultUrl = defaultUrl;
 	}
 	/**
 	 * Set allowed resources as URL pattern, e.g. "/WEB-INF/res/*.jsp",
 	 * The parameter can be any Ant-style pattern parsable by AntPathMatcher.
 	 * @see org.springframework.util.AntPathMatcher
 	 */
 	public void setAllowedResources(String allowedResources) {
 		this.allowedResources = allowedResources;
 	}
 	/**
 	 * Set the content type of the target resource (typically a JSP).
 	 * Default is none, which is appropriate when including resources.
 	 * <p>For directly accessing resources, for example to leverage this
 	 * servlet's last-modified support, specify a content type here.
 	 * Note that a content type header in the target JSP will be ignored
 	 * when including the resource via a RequestDispatcher include.
 	 */
 	public void setContentType(String contentType) {
 		this.contentType = contentType;
 	}
 	/**
 	 * Set whether to apply the file timestamp of the target resource
 	 * as last-modified value. Default is "false".
 	 * <p>This is mainly intended for JSP targets that don't generate
 	 * session-specific or database-driven content: Such files can be
 	 * cached by the browser as long as the last-modified timestamp
 	 * of the JSP file doesn't change.
 	 * <p>This will only work correctly with expanded WAR files that
 	 * allow access to the file timestamps. Else, the startup time
 	 * of this servlet is returned.
 	 */
 	public void setApplyLastModified(boolean applyLastModified) {
 		this.applyLastModified = applyLastModified;
 	}
 	/**
 	 * Remember the startup time, using no last-modified time before it.
 	 */
 	@Override
 	protected void initServletBean() {
 		this.pathMatcher = getPathMatcher();
 		this.startupTime = System.currentTimeMillis();
 	}
 	/**
 	 * Return a {@link PathMatcher} to use for matching the "allowedResources" URL pattern.
 	 * <p>The default is {@link AntPathMatcher}.
 	 * @see #setAllowedResources
 	 * @see org.springframework.util.AntPathMatcher
 	 */
 	protected PathMatcher getPathMatcher() {
 		return new AntPathMatcher();
 	}
 	/**
 	 * Determine the URL of the target resource and include it.
 	 * @see #determineResourceUrl
 	 */
 	@Override
 	protected final void doGet(HttpServletRequest request, HttpServletResponse response)
 			throws ServletException, IOException {
 		// Determine URL of resource to include...
 		String resourceUrl = determineResourceUrl(request);
 		if (resourceUrl != null) {
 			try {
 				doInclude(request, response, resourceUrl);
 			}
 			catch (ServletException ex) {
 				if (logger.isWarnEnabled()) {
 					logger.warn("Failed to include content of resource [" + resourceUrl + "]", ex);
 				}
 				// Try including default URL if appropriate.
 				if (!includeDefaultUrl(request, response)) {
 					throw ex;
 				}
 			}
 			catch (IOException ex) {
 				if (logger.isWarnEnabled()) {
 					logger.warn("Failed to include content of resource [" + resourceUrl + "]", ex);
 				}
 				// Try including default URL if appropriate.
 				if (!includeDefaultUrl(request, response)) {
 					throw ex;
 				}
 			}
 		}
 		// No resource URL specified -> try to include default URL.
 		else if (!includeDefaultUrl(request, response)) {
 			throw new ServletException("No target resource URL found for request");
 		}
 	}
 	/**
 	 * Determine the URL of the target resource of this request.
 	 * <p>Default implementation returns the value of the "resource" parameter.
 	 * Can be overridden in subclasses.
 	 * @param request current HTTP request
 	 * @return the URL of the target resource, or {@code null} if none found
 	 * @see #RESOURCE_PARAM_NAME
 	 */
 	protected String determineResourceUrl(HttpServletRequest request) {
 		return request.getParameter(RESOURCE_PARAM_NAME);
 	}
 	/**
 	 * Include the specified default URL, if appropriate.
 	 * @param request current HTTP request
 	 * @param response current HTTP response
 	 * @return whether a default URL was included
 	 * @throws ServletException if thrown by the RequestDispatcher
 	 * @throws IOException if thrown by the RequestDispatcher
 	 */
 	private boolean includeDefaultUrl(HttpServletRequest request, HttpServletResponse response)
 		throws ServletException, IOException {
 		if (this.defaultUrl == null) {
 			return false;
 		}
 		doInclude(request, response, this.defaultUrl);
 		return true;
 	}
 	/**
 	 * Include the specified resource via the RequestDispatcher.
 	 * @param request current HTTP request
 	 * @param response current HTTP response
 	 * @param resourceUrl the URL of the target resource
 	 * @throws ServletException if thrown by the RequestDispatcher
 	 * @throws IOException if thrown by the RequestDispatcher
 	 */
 	private void doInclude(HttpServletRequest request, HttpServletResponse response, String resourceUrl)
 			throws ServletException, IOException {
 		if (this.contentType != null) {
 			response.setContentType(this.contentType);
 		}
 		String[] resourceUrls = StringUtils.tokenizeToStringArray(resourceUrl, RESOURCE_URL_DELIMITERS);
 		for (String url : resourceUrls) {
 			// check whether URL matches allowed resources
 			if (this.allowedResources != null && !this.pathMatcher.match(this.allowedResources, url)) {
 				throw new ServletException("Resource [" + url +
 						"] does not match allowed pattern [" + this.allowedResources + "]");
 			}
 			if (logger.isDebugEnabled()) {
 				logger.debug("Including resource [" + url + "]");
 			}
 			RequestDispatcher rd = request.getRequestDispatcher(url);
 			rd.include(request, response);
 		}
 	}
 	/**
 	 * Return the last-modified timestamp of the file that corresponds
 	 * to the target resource URL (i.e. typically the request ".jsp" file).
 	 * Will simply return -1 if "applyLastModified" is false (the default).
 	 * <p>Returns no last-modified date before the startup time of this servlet,
 	 * to allow for message resolution etc that influences JSP contents,
 	 * assuming that those background resources might have changed on restart.
 	 * <p>Returns the startup time of this servlet if the file that corresponds
 	 * to the target resource URL couldn't be resolved (for example, because
 	 * the WAR is not expanded).
 	 * @see #determineResourceUrl
 	 * @see #getFileTimestamp
 	 */
 	@Override
 	protected final long getLastModified(HttpServletRequest request) {
 		if (this.applyLastModified) {
 			String resourceUrl = determineResourceUrl(request);
 			if (resourceUrl == null) {
 				resourceUrl = this.defaultUrl;
 			}
 			if (resourceUrl != null) {
 				String[] resourceUrls = StringUtils.tokenizeToStringArray(resourceUrl, RESOURCE_URL_DELIMITERS);
 				long latestTimestamp = -1;
 				for (String url : resourceUrls) {
 					long timestamp = getFileTimestamp(url);
 					if (timestamp > latestTimestamp) {
 						latestTimestamp = timestamp;
 					}
 				}
 				return (latestTimestamp > this.startupTime ? latestTimestamp : this.startupTime);
 			}
 		}
 		return -1;
 	}
 	/**
 	 * Return the file timestamp for the given resource.
 	 * @param resourceUrl the URL of the resource
 	 * @return the file timestamp in milliseconds, or -1 if not determinable
 	 */
 	protected long getFileTimestamp(String resourceUrl) {
 		ServletContextResource resource = new ServletContextResource(getServletContext(), resourceUrl);
 		try {
 			long lastModifiedTime = resource.lastModified();
 			if (logger.isDebugEnabled()) {
 				logger.debug("Last-modified timestamp of " + resource + " is " + lastModifiedTime);
 			}
 			return lastModifiedTime;
 		}
 		catch (IOException ex) {
 			if (logger.isWarnEnabled()) {
 				logger.warn("Couldn't retrieve last-modified timestamp of " + resource +
 						" - using ResourceServlet startup time");
 			}
 			return -1;
 		}
 	}
 }