首先看到web.xml中的配置

<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
<!-- 这里配置你的ShiroFilterFactoryBean的spring配置文件 -->
</param-value>
</context-param>
<filter>
<filter-name>shiroFilter</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
<async-supported>true</async-supported>
<init-param>
<param-name>targetFilterLifecycle</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>shiroFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
现在就引出一个问题,这里配置了ShiroFilterFactoryBean 和 DelegatingFilterProxy对象,显然这两个只是一个工厂Bean和一个委托代理对象  那么真正的shiro入口过滤器在哪儿 ?
我们进入DelegatingFilterProxy
发现其构造方法是空的
public DelegatingFilterProxy() {
}

 但是它的父类GenericFilterBean实现了InitializingBean, 那么就多了个afterPropertiesSet方法

GenericFilterBean

@Override
public void afterPropertiesSet() throws ServletException {
initFilterBean();
}

DelegatingFilterProxy

@Override
protected void initFilterBean() throws ServletException {
synchronized (this.delegateMonitor) {
if (this.delegate == null) {
// 这个是DelegatingFilterProxy配置的名字 shiroFilter
if (this.targetBeanName == null) {
this.targetBeanName = getFilterName();
}
WebApplicationContext wac = findWebApplicationContext();
if (wac != null) {
            //初始化
this.delegate = initDelegate(wac);
}
}
}
}
protected Filter initDelegate(WebApplicationContext wac) throws ServletException {
  //从spring上下文中根据shiroFilter(DelegatingFilterProxy配置的名字) 获取bean
Filter delegate = wac.getBean(getTargetBeanName(), Filter.class);
if (isTargetFilterLifecycle()) {
delegate.init(getFilterConfig());
}
return delegate;
}
 

AbstractApplicationContext

@Override
public <T> T getBean(String name, Class<T> requiredType) throws BeansException {
assertBeanFactoryActive();
return getBeanFactory().getBean(name, requiredType);
}

AbstractBeanFactory

@Override
public <T> T getBean(String name, Class<T> requiredType) throws BeansException {
return doGetBean(name, requiredType, null, false);
}
//最终走到了doGetBean
protected <T> T doGetBean(
final String name, final Class<T> requiredType, final Object[] args, boolean typeCheckOnly)
throws BeansException { final String beanName = transformedBeanName(name);
Object bean; // 根据web里面配置的shiroFilter的名字在spring容器中获取到了ShiroFilterFactoryBean
Object sharedInstance = getSingleton(beanName);
if (sharedInstance != null && args == null) {
// 通过工厂获取对象
bean = getObjectForBeanInstance(sharedInstance, name, beanName, null);
}return (T) bean;
}
protected Object getObjectForBeanInstance(
Object beanInstance, String name, String beanName, RootBeanDefinition mbd) {   //其中有这么一句,从工厂Bean中获取Bean实例
if (object == null) {
...
object = getObjectFromFactoryBean(factory, beanName, !synthetic);
}
return object;
}

FactoryBeanRegistrySupport  经过枯燥的源码调用 ,来到了大门口

private Object doGetObjectFromFactoryBean(final FactoryBean<?> factory, final String beanName)
throws BeanCreationException { Object object;
try {
else {
//调用ShiroFilterFactoryBean的getObjectct方法, ShiroFilterFactoryBean实现了FactoryBean
object = factory.getObject();
}
}
return object;
}

现在让我们来看看ShiroFilterFactoryBean

public Object getObject() throws Exception {
if (instance == null) {
instance = createInstance();
}
return instance;
}
protected AbstractShiroFilter createInstance() throws Exception {

    SecurityManager securityManager = getSecurityManager();

  //这里有个创建过滤连管理器的方法 我们也要看看
FilterChainManager manager = createFilterChainManager(); PathMatchingFilterChainResolver chainResolver = new PathMatchingFilterChainResolver();
chainResolver.setFilterChainManager(manager);
  //这里就是最终的那个shiro的入口Filter 是 AbstractShiroFilter的子类
return new SpringShiroFilter((WebSecurityManager) securityManager, chainResolver);
}

那么SpringShiroFilter就长这样,这个就是shiro的入口Filter,每次调用都会先调用它(doFilter方法在父类AbstractShiroFilter 中)

private static final class SpringShiroFilter extends AbstractShiroFilter {

        protected SpringShiroFilter(WebSecurityManager webSecurityManager, FilterChainResolver resolver) {
super();
if (webSecurityManager == null) {
throw new IllegalArgumentException("WebSecurityManager property cannot be null.");
}
setSecurityManager(webSecurityManager);
if (resolver != null) {
setFilterChainResolver(resolver);
}
}
}

然后我们再看看createFilterChainManager

protected FilterChainManager createFilterChainManager() {
     
    //其中包含了11个默认的过滤器
DefaultFilterChainManager manager = new DefaultFilterChainManager();
    //默认的11个过滤器
Map<String, Filter> defaultFilters = manager.getFilters();
// 添加登陆、登陆成功、没有认证 的url(如果设置了的话)
for (Filter filter : defaultFilters.values()) {
applyGlobalPropertiesIfNecessary(filter);
} /在xml文件的<property name="filters">中配置的过滤
Map<String, Filter> filters = getFilters();
if (!CollectionUtils.isEmpty(filters)) {
for (Map.Entry<String, Filter> entry : filters.entrySet()) {
          //拦截规则
String name = entry.getKey();
          //过滤器
Filter filter = entry.getValue();
          // 添加登陆、登陆成功、没有认证 的url(如果设置了的话)
applyGlobalPropertiesIfNecessary(filter);
          //设置名字
if (filter instanceof Nameable) {
((Nameable) filter).setName(name);
}
          //添加自定义的过滤器, 因为spring容器启动时初始化过自定义的过滤器,所以这个为初始化参数为false
manager.addFilter(name, filter, false);
}
} //<property name="filterChainDefinitions">中设置的规则与过滤器
Map<String, String> chains = getFilterChainDefinitionMap();
if (!CollectionUtils.isEmpty(chains)) {
       //绑定规则与过滤器链
for (Map.Entry<String, String> entry : chains.entrySet()) {
           //规则
String url = entry.getKey();
          //过滤器链中的过滤器名称
String chainDefinition = entry.getValue();
          //创建过滤器链
manager.createChain(url, chainDefinition);
}
} return manager;
}
// 给 “每一个” 满足类型的过滤器添加添加登陆、登陆成功、没有认证 的url(如果设置了的话)
private void applyGlobalPropertiesIfNecessary(Filter filter) {
// 需要是AccessControlFilter类型
applyLoginUrlIfNecessary(filter);
// 需要是 AuthenticationFilter类型
applySuccessUrlIfNecessary(filter);
//需要是AuthorizationFilter 类型
applyUnauthorizedUrlIfNecessary(filter);
}
DefaultFilterChainManager
//创建过滤链
public void createChain(String chainName, String chainDefinition) {
// 过滤器可以写成这样 { "authc", "roles[admin,user]", "perms[file:edit]" }
String[] filterTokens = splitChainDefinition(chainDefinition); //这里让每一个PathConfigProcessor类型的过滤器都有该过滤器对应的所有规则 这里遍历的是过滤链字符串
for (String token : filterTokens) {
String[] nameConfigPair = toNameConfigPair(token);
//添加过滤器到过滤链(一个规则对应一条过滤链)
addToChain(chainName, nameConfigPair[0], nameConfigPair[1]);
}
}
//添加过滤器到过滤链
public void addToChain(String chainName, String filterName, String chainSpecificFilterConfig) {
//根据名称获取过滤器
Filter filter = getFilter(filterName);
//配置过滤链
applyChainConfig(chainName, filter, chainSpecificFilterConfig); NamedFilterList chain = ensureChain(chainName);
chain.add(filter);
}
//配置过滤链
protected void applyChainConfig(String chainName, Filter filter, String chainSpecificFilterConfig) {
//如果当前过滤器是PathConfigProcessor类型 处理之
if (filter instanceof PathConfigProcessor) {
((PathConfigProcessor) filter).processPathConfig(chainName, chainSpecificFilterConfig);
}
}

PathMatchingFilter 这里将同一过滤器的所有规则设置给当前过滤器  比如 /aa=anon  /bb=anon  如果当前请求的路径是/aa 它对应的过滤器是anon 这里的appliedPaths就会有 /aa 和 /bb两个元素

    简单理解为当前拦截路径所对应的过滤器类型 对应的拦截路径(--!)

public Filter processPathConfig(String path, String config) {
String[] values = null;
if (config != null) {
values = split(config);
}
// 添加过滤链的名称
this.appliedPaths.put(path, values);
return this;
}
小结:
  1、在启动后生成 shiroFilter -- SpringShiroFilter 入口过滤器(ShiroFilterFactoryBean类中)
  2、在会以拦截规则为key,后面的过滤器生成一条过滤链为 value的形式生成存放在map中(DefaultFilterChainManager类中)
  3、会给每个AccessControlFilter类型过滤器设置 登陆、登陆成功、没有认证 的url(ShiroFilterFactoryBean类中)
04-23 07:00