/*
* Copyright 2002-2009 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.handler;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.core.Ordered;
import org.springframework.util.AntPathMatcher;
import org.springframework.util.Assert;
import org.springframework.util.PathMatcher;
import org.springframework.web.context.request.WebRequestInterceptor;
import org.springframework.web.context.support.WebApplicationObjectSupport;
import org.springframework.web.servlet.HandlerExecutionChain;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.HandlerMapping;
import org.springframework.web.util.UrlPathHelper;
/**
* Abstract base class for {@link org.springframework.web.servlet.HandlerMapping}
* implementations. Supports ordering, a default handler, handler interceptors,
* including handler interceptors mapped by path patterns.
*
* <p>Note: This base class does <i>not</i> support exposure of the
* {@link #PATH_WITHIN_HANDLER_MAPPING_ATTRIBUTE}. Support for this attribute
* is up to concrete subclasses, typically based on request URL mappings.
*
* @author Juergen Hoeller
* @author Rossen Stoyanchev
* @since 07.04.2003
* @see #getHandlerInternal
* @see #setDefaultHandler
* @see #setAlwaysUseFullPath
* @see #setUrlDecode
* @see org.springframework.util.AntPathMatcher
* @see #setInterceptors
* @see org.springframework.web.servlet.HandlerInterceptor
*/
public abstract class AbstractHandlerMapping extends WebApplicationObjectSupport
implements HandlerMapping, Ordered {
private int order = Integer.MAX_VALUE; // default: same as non-Ordered
private Object defaultHandler;
private UrlPathHelper urlPathHelper = new UrlPathHelper();
private PathMatcher pathMatcher = new AntPathMatcher();
private final List<Object> interceptors = new ArrayList<Object>();
private final List<HandlerInterceptor> adaptedInterceptors = new ArrayList<HandlerInterceptor>();
private final List<MappedInterceptor> mappedInterceptors = new ArrayList<MappedInterceptor>();
/**
* Specify the order value for this HandlerMapping bean.
* <p>Default value is <code>Integer.MAX_VALUE</code>, meaning that it's non-ordered.
* @see org.springframework.core.Ordered#getOrder()
*/
public final void setOrder(int order) {
this.order = order;
}
public final int getOrder() {
return this.order;
}
/**
* Set the default handler for this handler mapping.
* This handler will be returned if no specific mapping was found.
* <p>Default is <code>null</code>, indicating no default handler.
*/
public void setDefaultHandler(Object defaultHandler) {
this.defaultHandler = defaultHandler;
}
/**
* Return the default handler for this handler mapping,
* or <code>null</code> if none.
*/
public Object getDefaultHandler() {
return this.defaultHandler;
}
/**
* Set if URL lookup should always use the full path within the current servlet
* context. Else, the path within the current servlet mapping is used if applicable
* (that is, in the case of a ".../*" servlet mapping in web.xml).
* <p>Default is "false".
* @see org.springframework.web.util.UrlPathHelper#setAlwaysUseFullPath
*/
public void setAlwaysUseFullPath(boolean alwaysUseFullPath) {
this.urlPathHelper.setAlwaysUseFullPath(alwaysUseFullPath);
}
/**
* Set if context path and request URI should be URL-decoded. Both are returned
* <i>undecoded</i> by the Servlet API, in contrast to the servlet path.
* <p>Uses either the request encoding or the default encoding according
* to the Servlet spec (ISO-8859-1).
* @see org.springframework.web.util.UrlPathHelper#setUrlDecode
*/
public void setUrlDecode(boolean urlDecode) {
this.urlPathHelper.setUrlDecode(urlDecode);
}
/**
* Set if ";" (semicolon) content should be stripped from the request URI.
* @see org.springframework.web.util.UrlPathHelper#setRemoveSemicolonContent(boolean)
*/
public void setRemoveSemicolonContent(boolean removeSemicolonContent) {
this.urlPathHelper.setRemoveSemicolonContent(removeSemicolonContent);
}
/**
* Set the UrlPathHelper to use for resolution of lookup paths.
* <p>Use this to override the default UrlPathHelper with a custom subclass,
* or to share common UrlPathHelper settings across multiple HandlerMappings
* and MethodNameResolvers.
*/
public void setUrlPathHelper(UrlPathHelper urlPathHelper) {
Assert.notNull(urlPathHelper, "UrlPathHelper must not be null");
this.urlPathHelper = urlPathHelper;
}
/**
* Return the UrlPathHelper implementation to use for resolution of lookup paths.
*/
public UrlPathHelper getUrlPathHelper() {
return urlPathHelper;
}
/**
* Set the PathMatcher implementation to use for matching URL paths
* against registered URL patterns. Default is AntPathMatcher.
* @see org.springframework.util.AntPathMatcher
*/
public void setPathMatcher(PathMatcher pathMatcher) {
Assert.notNull(pathMatcher, "PathMatcher must not be null");
this.pathMatcher = pathMatcher;
}
/**
* Return the PathMatcher implementation to use for matching URL paths
* against registered URL patterns.
*/
public PathMatcher getPathMatcher() {
return this.pathMatcher;
}
/**
* Set the interceptors to apply for all handlers mapped by this handler mapping.
* <p>Supported interceptor types are HandlerInterceptor, WebRequestInterceptor, and MappedInterceptor.
* Mapped interceptors apply only to request URLs that match its path patterns.
* Mapped interceptor beans are also detected by type during initialization.
* @param interceptors array of handler interceptors, or <code>null</code> if none
* @see #adaptInterceptor
* @see org.springframework.web.servlet.HandlerInterceptor
* @see org.springframework.web.context.request.WebRequestInterceptor
*/
public void setInterceptors(Object[] interceptors) {
this.interceptors.addAll(Arrays.asList(interceptors));
}
/**
* Initializes the interceptors.
* @see #extendInterceptors(java.util.List)
* @see #initInterceptors()
*/
@Override
protected void initApplicationContext() throws BeansException {
extendInterceptors(this.interceptors);
detectMappedInterceptors(this.mappedInterceptors);
initInterceptors();
}
/**
* Extension hook that subclasses can override to register additional interceptors,
* given the configured interceptors (see {@link #setInterceptors}).
* <p>Will be invoked before {@link #initInterceptors()} adapts the specified
* interceptors into {@link HandlerInterceptor} instances.
* <p>The default implementation is empty.
* @param interceptors the configured interceptor List (never <code>null</code>),
* allowing to add further interceptors before as well as after the existing
* interceptors
*/
protected void extendInterceptors(List<Object> interceptors) {
}
/**
* Detects beans of type {@link MappedInterceptor} and adds them to the list of mapped interceptors.
* This is done in addition to any {@link MappedInterceptor}s that may have been provided via
* {@link #setInterceptors(Object[])}. Subclasses can override this method to change that.
*
* @param mappedInterceptors an empty list to add MappedInterceptor types to
*/
protected void detectMappedInterceptors(List<MappedInterceptor> mappedInterceptors) {
mappedInterceptors.addAll(
BeanFactoryUtils.beansOfTypeIncludingAncestors(
getApplicationContext(),MappedInterceptor.class, true, false).values());
}
/**
* Initialize the specified interceptors, checking for {@link MappedInterceptor}s and adapting
* HandlerInterceptors where necessary.
* @see #setInterceptors
* @see #adaptInterceptor
*/
protected void initInterceptors() {
if (!this.interceptors.isEmpty()) {
for (int i = 0; i < this.interceptors.size(); i++) {
Object interceptor = this.interceptors.get(i);
if (interceptor == null) {
throw new IllegalArgumentException("Entry number " + i + " in interceptors array is null");
}
if (interceptor instanceof MappedInterceptor) {
mappedInterceptors.add((MappedInterceptor) interceptor);
}
else {
adaptedInterceptors.add(adaptInterceptor(interceptor));
}
}
}
}
/**
* Adapt the given interceptor object to the HandlerInterceptor interface.
* <p>Supported interceptor types are HandlerInterceptor and WebRequestInterceptor.
* Each given WebRequestInterceptor will be wrapped in a WebRequestHandlerInterceptorAdapter.
* Can be overridden in subclasses.
* @param interceptor the specified interceptor object
* @return the interceptor wrapped as HandlerInterceptor
* @see org.springframework.web.servlet.HandlerInterceptor
* @see org.springframework.web.context.request.WebRequestInterceptor
* @see WebRequestHandlerInterceptorAdapter
*/
protected HandlerInterceptor adaptInterceptor(Object interceptor) {
if (interceptor instanceof HandlerInterceptor) {
return (HandlerInterceptor) interceptor;
}
else if (interceptor instanceof WebRequestInterceptor) {
return new WebRequestHandlerInterceptorAdapter((WebRequestInterceptor) interceptor);
}
else {
throw new IllegalArgumentException("Interceptor type not supported: " + interceptor.getClass().getName());
}
}
/**
* Return the adapted interceptors as HandlerInterceptor array.
* @return the array of HandlerInterceptors, or <code>null</code> if none
*/
protected final HandlerInterceptor[] getAdaptedInterceptors() {
int count = adaptedInterceptors.size();
return (count > 0) ? adaptedInterceptors.toArray(new HandlerInterceptor[count]) : null;
}
/**
* Return all configured {@link MappedInterceptor}s as an array.
* @return the array of {@link MappedInterceptor}s, or <code>null</code> if none
*/
protected final MappedInterceptor[] getMappedInterceptors() {
int count = mappedInterceptors.size();
return (count > 0) ? mappedInterceptors.toArray(new MappedInterceptor[count]) : null;
}
/**
* Look up a handler for the given request, falling back to the default
* handler if no specific one is found.
* @param request current HTTP request
* @return the corresponding handler instance, or the default handler
* @see #getHandlerInternal
*/
public final HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
Object handler = getHandlerInternal(request);
if (handler == null) {
handler = getDefaultHandler();
}
if (handler == null) {
return null;
}
// Bean name or resolved handler?
if (handler instanceof String) {
String handlerName = (String) handler;
handler = getApplicationContext().getBean(handlerName);
}
return getHandlerExecutionChain(handler, request);
}
/**
* Look up a handler for the given request, returning <code>null</code> if no
* specific one is found. This method is called by {@link #getHandler};
* a <code>null</code> return value will lead to the default handler, if one is set.
* <p>Note: This method may also return a pre-built {@link HandlerExecutionChain},
* combining a handler object with dynamically determined interceptors.
* Statically specified interceptors will get merged into such an existing chain.
* @param request current HTTP request
* @return the corresponding handler instance, or <code>null</code> if none found
* @throws Exception if there is an internal error
*/
protected abstract Object getHandlerInternal(HttpServletRequest request) throws Exception;
/**
* Build a HandlerExecutionChain for the given handler, including applicable interceptors.
* <p>The default implementation simply builds a standard HandlerExecutionChain with
* the given handler, the handler mapping's common interceptors, and any {@link MappedInterceptor}s
* matching to the current request URL. Subclasses may
* override this in order to extend/rearrange the list of interceptors.
* <p><b>NOTE:</b> The passed-in handler object may be a raw handler or a pre-built
* HandlerExecutionChain. This method should handle those two cases explicitly,
* either building a new HandlerExecutionChain or extending the existing chain.
* <p>For simply adding an interceptor, consider calling <code>super.getHandlerExecutionChain</code>
* and invoking {@link HandlerExecutionChain#addInterceptor} on the returned chain object.
* @param handler the resolved handler instance (never <code>null</code>)
* @param request current HTTP request
* @return the HandlerExecutionChain (never <code>null</code>)
* @see #getAdaptedInterceptors()
*/
protected HandlerExecutionChain getHandlerExecutionChain(Object handler, HttpServletRequest request) {
HandlerExecutionChain chain =
(handler instanceof HandlerExecutionChain) ?
(HandlerExecutionChain) handler : new HandlerExecutionChain(handler);
chain.addInterceptors(getAdaptedInterceptors());
String lookupPath = urlPathHelper.getLookupPathForRequest(request);
for (MappedInterceptor mappedInterceptor : mappedInterceptors) {
if (mappedInterceptor.matches(lookupPath, pathMatcher)) {
chain.addInterceptor(mappedInterceptor.getInterceptor());
}
}
return chain;
}
}