GenericFilterBean

java.lang.Object
- org.springframework.web.filter.GenericFilterBean

All Implemented Interfaces:

Aware, BeanNameAware, DisposableBean, InitializingBean, EnvironmentAware, ServletContextAware

Direct Known Subclasses:

DelegatingFilterProxy, OncePerRequestFilter
```
public abstract class GenericFilterBean
extends java.lang.Object
implements BeanNameAware, EnvironmentAware, ServletContextAware, InitializingBean, DisposableBean
```
Simple base implementation of javax.servlet.Filter which treats its config parameters (init-param entries within the filter tag in web.xml) as bean properties.
A handy superclass for any type of filter. Type conversion of config parameters is automatic, with the corresponding setter method getting invoked with the converted value. It is also possible for subclasses to specify required properties. Parameters without matching bean property setter will simply be ignored.
This filter leaves actual filtering to subclasses, which have to implement the javax.servlet.Filter#doFilter method.
This generic filter base class has no dependency on the Spring ApplicationContext concept. Filters usually don't load their own context but rather access service beans from the Spring root application context, accessible via the filter's ServletContext (see WebApplicationContextUtils).

Since:

06.12.2003

Author:

Juergen Hoeller

See Also:

addRequiredProperty(java.lang.String), initFilterBean(), #doFilter

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`private static class`	`GenericFilterBean.FilterConfigPropertyValues` PropertyValues implementation created from FilterConfig init parameters.

Field Summary

Fields
Modifier and Type	Field and Description
`private java.lang.String`	`beanName`
`private Environment`	`environment`
`private FilterConfig`	`filterConfig`
`protected Log`	`logger` Logger available to subclasses
`private java.util.Set<java.lang.String>`	`requiredProperties` Set of required properties (Strings) that must be supplied as config parameters to this filter.
`private ServletContext`	`servletContext`

Constructor Summary

Constructors
Constructor and Description

GenericFilterBean()

Constructors
Constructor and Description
`GenericFilterBean()`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected void`	`addRequiredProperty(java.lang.String property)` Subclasses can invoke this method to specify that this property (which must match a JavaBean property they expose) is mandatory, and must be supplied as a config parameter.
`void`	`afterPropertiesSet()` Calls the `initFilterBean()` method that might contain custom initialization of a subclass.
`void`	`destroy()` Subclasses may override this to perform custom filter shutdown.
`FilterConfig`	`getFilterConfig()` Make the FilterConfig of this filter available, if any.
`protected java.lang.String`	`getFilterName()` Make the name of this filter available to subclasses.
`protected ServletContext`	`getServletContext()` Make the ServletContext of this filter available to subclasses.
`void`	`init(FilterConfig filterConfig)` Standard way of initializing this filter.
`protected void`	`initBeanWrapper(BeanWrapper bw)` Initialize the BeanWrapper for this GenericFilterBean, possibly with custom editors.
`protected void`	`initFilterBean()` Subclasses may override this to perform custom initialization.
`void`	`setBeanName(java.lang.String beanName)` Stores the bean name as defined in the Spring bean factory.
`void`	`setEnvironment(Environment environment)` Set the `Environment` that this object runs in.
`void`	`setServletContext(ServletContext servletContext)` Stores the ServletContext that the bean factory runs in.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - logger
```
protected final Log logger
```
    Logger available to subclasses
  - requiredProperties
```
private final java.util.Set<java.lang.String> requiredProperties
```
    Set of required properties (Strings) that must be supplied as config parameters to this filter.
  - filterConfig
```
private FilterConfig filterConfig
```
  - beanName
```
private java.lang.String beanName
```
  - environment
```
private Environment environment
```
  - servletContext
```
private ServletContext servletContext
```
- Constructor Detail
  - GenericFilterBean
```
public GenericFilterBean()
```
- Method Detail
  - setBeanName
```
public final void setBeanName(java.lang.String beanName)
```
    Stores the bean name as defined in the Spring bean factory.
    Only relevant in case of initialization as bean, to have a name as fallback to the filter name usually provided by a FilterConfig instance.
    
    Specified by:
    
    setBeanName in interface BeanNameAware
    
    Parameters:
    
    beanName - the name of the bean in the factory. Note that this name is the actual bean name used in the factory, which may differ from the originally specified name: in particular for inner bean names, the actual bean name might have been made unique through appending "#..." suffixes. Use the BeanFactoryUtils.originalBeanName(String) method to extract the original bean name (without suffix), if desired.
    
    See Also:
    
    BeanNameAware, getFilterName()
  - setEnvironment
```
public void setEnvironment(Environment environment)
```
    Set the Environment that this object runs in.
    Any environment set here overrides the StandardServletEnvironment provided by default.
    This Environment object is used only for resolving placeholders in resource paths passed into init-parameters for this filter. If no init-params are used, this Environment can be essentially ignored.
    
    Specified by:
    
    setEnvironment in interface EnvironmentAware
    
    See Also:
    
    init(FilterConfig)
  - setServletContext
```
public final void setServletContext(ServletContext servletContext)
```
    Stores the ServletContext that the bean factory runs in.
    Only relevant in case of initialization as bean, to have a ServletContext as fallback to the context usually provided by a FilterConfig instance.
    
    Specified by:
    
    setServletContext in interface ServletContextAware
    
    Parameters:
    
    servletContext - ServletContext object to be used by this object
    
    See Also:
    
    ServletContextAware, getServletContext()
  - afterPropertiesSet
```
public void afterPropertiesSet()
                        throws ServletException
```
    Calls the initFilterBean() method that might contain custom initialization of a subclass.
    Only relevant in case of initialization as bean, where the standard init(FilterConfig) method won't be called.
    
    Specified by:
    
    afterPropertiesSet in interface InitializingBean
    
    Throws:
    
    ServletException
    
    See Also:
    
    initFilterBean(), #init(javax.servlet.FilterConfig)
  - addRequiredProperty
```
protected final void addRequiredProperty(java.lang.String property)
```
    Subclasses can invoke this method to specify that this property (which must match a JavaBean property they expose) is mandatory, and must be supplied as a config parameter. This should be called from the constructor of a subclass.
    This method is only relevant in case of traditional initialization driven by a FilterConfig instance.
    
    Parameters:
    
    property - name of the required property
  - init
```
public final void init(FilterConfig filterConfig)
                throws ServletException
```
    Standard way of initializing this filter. Map config parameters onto bean properties of this filter, and invoke subclass initialization.
    
    Parameters:
    
    filterConfig - the configuration for this filter
    
    Throws:
    
    ServletException - if bean properties are invalid (or required properties are missing), or if subclass initialization fails.
    
    See Also:
    
    initFilterBean()
  - initBeanWrapper
```
protected void initBeanWrapper(BeanWrapper bw)
                        throws BeansException
```
    Initialize the BeanWrapper for this GenericFilterBean, possibly with custom editors.
    This default implementation is empty.
    
    Parameters:
    
    bw - the BeanWrapper to initialize
    
    Throws:
    
    BeansException - if thrown by BeanWrapper methods
    
    See Also:
    
    PropertyEditorRegistry.registerCustomEditor(java.lang.Class<?>, java.beans.PropertyEditor)
  - getFilterConfig
```
public final FilterConfig getFilterConfig()
```
    Make the FilterConfig of this filter available, if any. Analogous to GenericServlet's getServletConfig().
    Public to resemble the getFilterConfig() method of the Servlet Filter version that shipped with WebLogic 6.1.
    
    Returns:
    
    the FilterConfig instance, or null if none available
    
    See Also:
    
    javax.servlet.GenericServlet#getServletConfig()
  - getFilterName
```
protected final java.lang.String getFilterName()
```
    Make the name of this filter available to subclasses. Analogous to GenericServlet's getServletName().
    Takes the FilterConfig's filter name by default. If initialized as bean in a Spring application context, it falls back to the bean name as defined in the bean factory.
    
    Returns:
    
    the filter name, or null if none available
    
    See Also:
    
    javax.servlet.GenericServlet#getServletName(), javax.servlet.FilterConfig#getFilterName(), setBeanName(java.lang.String)
  - getServletContext
```
protected final ServletContext getServletContext()
```
    Make the ServletContext of this filter available to subclasses. Analogous to GenericServlet's getServletContext().
    Takes the FilterConfig's ServletContext by default. If initialized as bean in a Spring application context, it falls back to the ServletContext that the bean factory runs in.
    
    Returns:
    
    the ServletContext instance, or null if none available
    
    See Also:
    
    javax.servlet.GenericServlet#getServletContext(), javax.servlet.FilterConfig#getServletContext(), setServletContext(ServletContext)
  - initFilterBean
```
protected void initFilterBean()
                       throws ServletException
```
    Subclasses may override this to perform custom initialization. All bean properties of this filter will have been set before this method is invoked.
    Note: This method will be called from standard filter initialization as well as filter bean initialization in a Spring application context. Filter name and ServletContext will be available in both cases.
    This default implementation is empty.
    
    Throws:
    
    ServletException - if subclass initialization fails
    
    See Also:
    
    getFilterName(), getServletContext()
  - destroy
```
public void destroy()
```
    Subclasses may override this to perform custom filter shutdown.
    Note: This method will be called from standard filter destruction as well as filter bean destruction in a Spring application context.
    This default implementation is empty.
    
    Specified by:
    
    destroy in interface DisposableBean

Class GenericFilterBean

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

logger

requiredProperties

filterConfig

beanName

environment

servletContext

Constructor Detail

GenericFilterBean

Method Detail

setBeanName

setEnvironment

setServletContext

afterPropertiesSet

addRequiredProperty

init

initBeanWrapper

getFilterConfig

getFilterName

getServletContext

initFilterBean

destroy