Environment and Configuration

interface WebEnvironment extends Environment {
    /**
     * Returns the FilterChainResolver used to resolve filter chains for incoming requests.
     *
     * @return the FilterChainResolver instance
     */
    FilterChainResolver getFilterChainResolver();
    
    /**
     * Returns the ServletContext associated with this web environment.
     *
     * @return the ServletContext instance
     */
    ServletContext getServletContext();
    
    /**
     * Returns the WebSecurityManager instance for this environment.
     *
     * @return the WebSecurityManager instance
     */
    WebSecurityManager getWebSecurityManager();
    
    /**
     * Returns the configuration for Shiro's filter, providing default implementation.
     *
     * @return the ShiroFilterConfiguration instance
     */
    default ShiroFilterConfiguration getShiroFilterConfiguration() {
        return new ShiroFilterConfiguration();
    }
}

class DefaultWebEnvironment extends DefaultEnvironment implements MutableWebEnvironment {
    /**
     * Creates a new DefaultWebEnvironment instance.
     */
    public DefaultWebEnvironment();
    
    /**
     * Returns the ServletContext associated with this environment.
     *
     * @return the ServletContext instance
     */
    public ServletContext getServletContext();
    
    /**
     * Sets the ServletContext for this environment.
     *
     * @param servletContext the ServletContext to set
     */
    public void setServletContext(ServletContext servletContext);
    
    /**
     * Returns the WebSecurityManager for this environment.
     *
     * @return the WebSecurityManager instance
     */
    public WebSecurityManager getWebSecurityManager();
    
    /**
     * Sets the WebSecurityManager for this environment.
     *
     * @param webSecurityManager the WebSecurityManager to set
     */
    public void setWebSecurityManager(WebSecurityManager webSecurityManager);
}

interface MutableWebEnvironment extends WebEnvironment {
    /**
     * Sets the FilterChainResolver for this environment.
     *
     * @param filterChainResolver the FilterChainResolver to set
     */
    void setFilterChainResolver(FilterChainResolver filterChainResolver);
    
    /**
     * Sets the ServletContext for this environment.
     *
     * @param servletContext the ServletContext to set
     */
    void setServletContext(ServletContext servletContext);
    
    /**
     * Sets the WebSecurityManager for this environment.
     *
     * @param webSecurityManager the WebSecurityManager to set
     */
    void setWebSecurityManager(WebSecurityManager webSecurityManager);
}

class EnvironmentLoader {
    /** ServletContext attribute key for storing the WebEnvironment instance */
    public static final String ENVIRONMENT_ATTRIBUTE_KEY = "shiroEnvironment";
    
    /** ServletContext init parameter name for specifying custom environment class */
    public static final String ENVIRONMENT_CLASS_PARAM = "shiroEnvironmentClass";
    
    /** ServletContext init parameter name for specifying custom configuration locations */
    public static final String CONFIG_LOCATIONS_PARAM = "shiroConfigLocations";
    
    /**
     * Initializes Shiro environment in the given ServletContext.
     *
     * @param servletContext the ServletContext to initialize
     * @return the created WebEnvironment instance
     */
    public WebEnvironment initEnvironment(ServletContext servletContext) throws IllegalStateException;
    
    /**
     * Destroys the Shiro environment in the given ServletContext.
     *
     * @param servletContext the ServletContext to clean up
     */
    public void destroyEnvironment(ServletContext servletContext);
    
    /**
     * Hook for customizing the WebEnvironment after creation but before use.
     *
     * @param environment the WebEnvironment to customize
     */
    protected void customizeEnvironment(WebEnvironment environment);
    
    /**
     * Creates a WebEnvironment instance based on ServletContext configuration.
     *
     * @param sc the ServletContext
     * @return the created WebEnvironment instance
     */
    protected WebEnvironment createEnvironment(ServletContext sc);
}

class EnvironmentLoaderListener extends EnvironmentLoader implements ServletContextListener {
    /**
     * Initializes the Shiro environment when the web application starts.
     *
     * @param sce the ServletContextEvent
     */
    public void contextInitialized(ServletContextEvent sce);
    
    /**
     * Destroys the Shiro environment when the web application shuts down.
     *
     * @param sce the ServletContextEvent
     */
    public void contextDestroyed(ServletContextEvent sce);
}

abstract class ResourceBasedWebEnvironment extends DefaultWebEnvironment {
    /** Default configuration resource locations to search */
    public static final String DEFAULT_WEB_INI_RESOURCE_PATH = "/WEB-INF/shiro.ini";
    
    /**
     * Creates a new ResourceBasedWebEnvironment.
     */
    public ResourceBasedWebEnvironment();
    
    /**
     * Returns the configuration resource locations.
     *
     * @return array of resource location strings
     */
    public String[] getConfigLocations();
    
    /**
     * Sets the configuration resource locations.
     *
     * @param configLocations array of resource location strings
     */
    public void setConfigLocations(String[] configLocations);
    
    /**
     * Initializes the environment by loading configuration from resources.
     */
    public void init();
    
    /**
     * Creates objects from the loaded configuration.
     *
     * @return a Map of created objects
     */
    protected abstract Map<String, Object> getObjects();
}

class IniWebEnvironment extends ResourceBasedWebEnvironment {
    /** Default INI configuration resource path */
    public static final String DEFAULT_WEB_INI_RESOURCE_PATH = "/WEB-INF/shiro.ini";
    
    /**
     * Creates a new IniWebEnvironment that loads configuration from INI resources.
     */
    public IniWebEnvironment();
    
    /**
     * Returns the loaded INI configuration.
     *
     * @return the Ini instance
     */
    public Ini getIni();
    
    /**
     * Sets the INI configuration.
     *
     * @param ini the Ini instance to set
     */
    public void setIni(Ini ini);
    
    /**
     * Creates objects from the INI configuration.
     *
     * @return a Map of created objects from the INI
     */
    protected Map<String, Object> getObjects();
}

class IniFilterChainResolverFactory extends IniFactorySupport<FilterChainResolver> {
    /**
     * Creates a new IniFilterChainResolverFactory.
     */
    public IniFilterChainResolverFactory();
    
    /**
     * Returns the FilterConfig used for filter initialization.
     *
     * @return the FilterConfig instance
     */
    public FilterConfig getFilterConfig();
    
    /**
     * Sets the FilterConfig for filter initialization.
     *
     * @param filterConfig the FilterConfig to set
     */
    public void setFilterConfig(FilterConfig filterConfig);
    
    /**
     * Returns the global filters applied to all chains.
     *
     * @return List of global filter names
     */
    public List<String> getGlobalFilters();
    
    /**
     * Sets the global filters applied to all chains.
     *
     * @param globalFilters List of global filter names
     */
    public void setGlobalFilters(List<String> globalFilters);
    
    /**
     * Creates a FilterChainResolver instance from the given INI configuration.
     *
     * @param ini the INI configuration
     * @return the created FilterChainResolver
     */
    protected FilterChainResolver createInstance(Ini ini);
    
    /**
     * Creates default filter instances for the resolver.
     *
     * @return Map of filter name to Filter instance
     */
    protected Map<String, Filter> createDefaultFilterMap();
}

@Deprecated
class WebIniSecurityManagerFactory extends IniSecurityManagerFactory {
    /**
     * Creates a new WebIniSecurityManagerFactory using default web INI resource.
     */
    public WebIniSecurityManagerFactory();
    
    /**
     * Creates a new WebIniSecurityManagerFactory with the specified INI resource path.
     *
     * @param iniResourcePath the INI resource path
     */
    public WebIniSecurityManagerFactory(String iniResourcePath);
    
    /**
     * Creates a new WebIniSecurityManagerFactory with the given INI instance.
     *
     * @param ini the INI instance
     */
    public WebIniSecurityManagerFactory(Ini ini);
    
    /**
     * Creates a default SecurityManager instance suitable for web applications.
     *
     * @return DefaultWebSecurityManager instance
     */
    protected SecurityManager createDefaultInstance();
}

class ShiroFilterConfiguration {
    /** Default value for filterOncePerRequest */
    public static final boolean DEFAULT_FILTER_ONCE_PER_REQUEST = true;
    
    /** Default value for staticSecurityManagerEnabled */
    public static final boolean DEFAULT_STATIC_SECURITY_MANAGER_ENABLED = false;
    
    /**
     * Creates a new ShiroFilterConfiguration with default settings.
     */
    public ShiroFilterConfiguration();
    
    /**
     * Returns whether the filter should execute only once per request.
     *
     * @return true if filter executes once per request
     */
    public boolean isFilterOncePerRequest();
    
    /**
     * Sets whether the filter should execute only once per request.
     *
     * @param filterOncePerRequest true to execute once per request
     */
    public void setFilterOncePerRequest(boolean filterOncePerRequest);
    
    /**
     * Returns whether static SecurityManager access is enabled.
     *
     * @return true if static SecurityManager is enabled
     */
    public boolean isStaticSecurityManagerEnabled();
    
    /**
     * Sets whether static SecurityManager access is enabled.
     *
     * @param staticSecurityManagerEnabled true to enable static SecurityManager
     */
    public void setStaticSecurityManagerEnabled(boolean staticSecurityManagerEnabled);
}

// web.xml configuration
/*
<context-param>
    <param-name>shiroConfigLocations</param-name>
    <param-value>/WEB-INF/shiro.ini</param-value>
</context-param>

<listener>
    <listener-class>
        org.apache.shiro.web.env.EnvironmentLoaderListener
    </listener-class>
</listener>
*/

// Programmatic environment setup
public class ShiroEnvironmentConfig {
    public void initializeShiro(ServletContext servletContext) {
        EnvironmentLoader loader = new EnvironmentLoader();
        WebEnvironment environment = loader.initEnvironment(servletContext);
        
        // Environment is now available in ServletContext
        WebEnvironment env = (WebEnvironment) servletContext.getAttribute(
            EnvironmentLoader.ENVIRONMENT_ATTRIBUTE_KEY);
    }
}

public class CustomWebEnvironment extends DefaultWebEnvironment {
    @Override
    public void init() {
        super.init();
        
        // Custom initialization logic
        DefaultWebSecurityManager securityManager = new DefaultWebSecurityManager();
        setWebSecurityManager(securityManager);
        
        // Custom filter chain configuration
        PathMatchingFilterChainResolver chainResolver = new PathMatchingFilterChainResolver();
        setFilterChainResolver(chainResolver);
    }
}

// Register custom environment class
/*
<context-param>
    <param-name>shiroEnvironmentClass</param-name>
    <param-value>com.example.CustomWebEnvironment</param-value>
</context-param>
*/

// shiro.ini configuration file content example:
/*
[main]
# Configure security manager
securityManager = org.apache.shiro.web.mgt.DefaultWebSecurityManager

# Configure realm
myRealm = com.example.MyCustomRealm
securityManager.realms = $myRealm

# Configure session manager
sessionManager = org.apache.shiro.web.session.mgt.DefaultWebSessionManager
securityManager.sessionManager = $sessionManager

[urls]
/login = authc
/admin/** = authc, roles[admin]
/user/** = authc
/** = anon
*/

public void createFromIni() {
    Ini ini = Ini.fromResourcePath("/WEB-INF/shiro.ini");
    IniWebEnvironment environment = new IniWebEnvironment();
    environment.setIni(ini);
    environment.init();
}