Spring Framework

org.springframework.jndi
Class JndiObjectFactoryBean

java.lang.Object
  extended by org.springframework.jndi.JndiAccessor
      extended by org.springframework.jndi.JndiLocatorSupport
          extended by org.springframework.jndi.JndiObjectLocator
              extended by org.springframework.jndi.JndiObjectFactoryBean
All Implemented Interfaces:
Aware, BeanClassLoaderAware, FactoryBean<java.lang.Object>, InitializingBean

public class JndiObjectFactoryBean
extends JndiObjectLocator
implements FactoryBean<java.lang.Object>, BeanClassLoaderAware

FactoryBean that looks up a JNDI object. Exposes the object found in JNDI for bean references, e.g. for data access object's "dataSource" property in case of a DataSource.

The typical usage will be to register this as singleton factory (e.g. for a certain JNDI-bound DataSource) in an application context, and give bean references to application services that need it.

The default behavior is to look up the JNDI object on startup and cache it. This can be customized through the "lookupOnStartup" and "cache" properties, using a JndiObjectTargetSource underneath. Note that you need to specify a "proxyInterface" in such a scenario, since the actual JNDI object type is not known in advance.

Of course, bean classes in a Spring environment may lookup e.g. a DataSource from JNDI themselves. This class simply enables central configuration of the JNDI name, and easy switching to non-JNDI alternatives. The latter is particularly convenient for test setups, reuse in standalone clients, etc.

Note that switching to e.g. DriverManagerDataSource is just a matter of configuration: Simply replace the definition of this FactoryBean with a DriverManagerDataSource definition!

Since:
22.05.2003
Author:
Juergen Hoeller
See Also:
setProxyInterface(java.lang.Class), setLookupOnStartup(boolean), setCache(boolean), JndiObjectTargetSource

Field Summary
 
Fields inherited from class org.springframework.jndi.JndiLocatorSupport
CONTAINER_PREFIX
 
Fields inherited from class org.springframework.jndi.JndiAccessor
logger
 
Constructor Summary
JndiObjectFactoryBean()
           
 
Method Summary
 void afterPropertiesSet()
          Look up the JNDI object and store it.
protected  java.lang.Class createCompositeInterface(java.lang.Class[] interfaces)
          Create a composite interface Class for the given interfaces, implementing the given interfaces in one single Class.
 java.lang.Object getObject()
          Return the singleton JNDI object.
 java.lang.Class<?> getObjectType()
          Return the type of object that this FactoryBean creates, or null if not known in advance.
 boolean isSingleton()
          Is the object managed by this factory a singleton? That is, will FactoryBean.getObject() always return the same object (a reference that can be cached)?
protected  java.lang.Object lookupWithFallback()
          Lookup variant that that returns the specified "defaultObject" (if any) in case of lookup failure.
 void setBeanClassLoader(java.lang.ClassLoader classLoader)
          Callback that supplies the bean class loader to a bean instance.
 void setCache(boolean cache)
          Set whether to cache the JNDI object once it has been located.
 void setDefaultObject(java.lang.Object defaultObject)
          Specify a default object to fall back to if the JNDI lookup fails.
 void setExposeAccessContext(boolean exposeAccessContext)
          Set whether to expose the JNDI environment context for all access to the target object, i.e.
 void setLookupOnStartup(boolean lookupOnStartup)
          Set whether to look up the JNDI object on startup.
 void setProxyInterface(java.lang.Class proxyInterface)
          Specify the proxy interface to use for the JNDI object.
 void setProxyInterfaces(java.lang.Class[] proxyInterfaces)
          Specify multiple proxy interfaces to use for the JNDI object.
 
Methods inherited from class org.springframework.jndi.JndiObjectLocator
getExpectedType, getJndiName, lookup, setExpectedType, setJndiName
 
Methods inherited from class org.springframework.jndi.JndiLocatorSupport
convertJndiName, isResourceRef, lookup, lookup, setResourceRef
 
Methods inherited from class org.springframework.jndi.JndiAccessor
getJndiEnvironment, getJndiTemplate, setJndiEnvironment, setJndiTemplate
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

JndiObjectFactoryBean

public JndiObjectFactoryBean()
Method Detail

setProxyInterface

public void setProxyInterface(java.lang.Class proxyInterface)
Specify the proxy interface to use for the JNDI object.

Typically used in conjunction with "lookupOnStartup"=false and/or "cache"=false. Needs to be specified because the actual JNDI object type is not known in advance in case of a lazy lookup.

See Also:
setProxyInterfaces(java.lang.Class[]), setLookupOnStartup(boolean), setCache(boolean)

setProxyInterfaces

public void setProxyInterfaces(java.lang.Class[] proxyInterfaces)
Specify multiple proxy interfaces to use for the JNDI object.

Typically used in conjunction with "lookupOnStartup"=false and/or "cache"=false. Note that proxy interfaces will be autodetected from a specified "expectedType", if necessary.

See Also:
JndiObjectLocator.setExpectedType(java.lang.Class), setLookupOnStartup(boolean), setCache(boolean)

setLookupOnStartup

public void setLookupOnStartup(boolean lookupOnStartup)
Set whether to look up the JNDI object on startup. Default is "true".

Can be turned off to allow for late availability of the JNDI object. In this case, the JNDI object will be fetched on first access.

For a lazy lookup, a proxy interface needs to be specified.

See Also:
setProxyInterface(java.lang.Class), setCache(boolean)

setCache

public void setCache(boolean cache)
Set whether to cache the JNDI object once it has been located. Default is "true".

Can be turned off to allow for hot redeployment of JNDI objects. In this case, the JNDI object will be fetched for each invocation.

For hot redeployment, a proxy interface needs to be specified.

See Also:
setProxyInterface(java.lang.Class), setLookupOnStartup(boolean)

setExposeAccessContext

public void setExposeAccessContext(boolean exposeAccessContext)
Set whether to expose the JNDI environment context for all access to the target object, i.e. for all method invocations on the exposed object reference.

Default is "false", i.e. to only expose the JNDI context for object lookup. Switch this flag to "true" in order to expose the JNDI environment (including the authorization context) for each method invocation, as needed by WebLogic for JNDI-obtained factories (e.g. JDBC DataSource, JMS ConnectionFactory) with authorization requirements.


setDefaultObject

public void setDefaultObject(java.lang.Object defaultObject)
Specify a default object to fall back to if the JNDI lookup fails. Default is none.

This can be an arbitrary bean reference or literal value. It is typically used for literal values in scenarios where the JNDI environment might define specific config settings but those are not required to be present.

Note: This is only supported for lookup on startup.

See Also:
setLookupOnStartup(boolean)

setBeanClassLoader

public void setBeanClassLoader(java.lang.ClassLoader classLoader)
Description copied from interface: BeanClassLoaderAware
Callback that supplies the bean class loader to a bean instance.

Invoked after the population of normal bean properties but before an initialization callback such as InitializingBean's InitializingBean.afterPropertiesSet() method or a custom init-method.

Specified by:
setBeanClassLoader in interface BeanClassLoaderAware
Parameters:
classLoader - the owning class loader; may be null in which case a default ClassLoader must be used, for example the ClassLoader obtained via ClassUtils.getDefaultClassLoader()

afterPropertiesSet

public void afterPropertiesSet()
                        throws java.lang.IllegalArgumentException,
                               javax.naming.NamingException
Look up the JNDI object and store it.

Specified by:
afterPropertiesSet in interface InitializingBean
Overrides:
afterPropertiesSet in class JndiObjectLocator
Throws:
java.lang.IllegalArgumentException
javax.naming.NamingException

lookupWithFallback

protected java.lang.Object lookupWithFallback()
                                       throws javax.naming.NamingException
Lookup variant that that returns the specified "defaultObject" (if any) in case of lookup failure.

Returns:
the located object, or the "defaultObject" as fallback
Throws:
javax.naming.NamingException - in case of lookup failure without fallback
See Also:
setDefaultObject(java.lang.Object)

getObject

public java.lang.Object getObject()
Return the singleton JNDI object.

Specified by:
getObject in interface FactoryBean<java.lang.Object>
Returns:
an instance of the bean (can be null)
See Also:
FactoryBeanNotInitializedException

getObjectType

public java.lang.Class<?> getObjectType()
Description copied from interface: FactoryBean
Return the type of object that this FactoryBean creates, or null if not known in advance.

This allows one to check for specific types of beans without instantiating objects, for example on autowiring.

In the case of implementations that are creating a singleton object, this method should try to avoid singleton creation as far as possible; it should rather estimate the type in advance. For prototypes, returning a meaningful type here is advisable too.

This method can be called before this FactoryBean has been fully initialized. It must not rely on state created during initialization; of course, it can still use such state if available.

NOTE: Autowiring will simply ignore FactoryBeans that return null here. Therefore it is highly recommended to implement this method properly, using the current state of the FactoryBean.

Specified by:
getObjectType in interface FactoryBean<java.lang.Object>
Returns:
the type of object that this FactoryBean creates, or null if not known at the time of the call
See Also:
ListableBeanFactory.getBeansOfType(java.lang.Class)

isSingleton

public boolean isSingleton()
Description copied from interface: FactoryBean
Is the object managed by this factory a singleton? That is, will FactoryBean.getObject() always return the same object (a reference that can be cached)?

NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from getObject() might get cached by the owning BeanFactory. Hence, do not return true unless the FactoryBean always exposes the same reference.

The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.

NOTE: This method returning false does not necessarily indicate that returned objects are independent instances. An implementation of the extended SmartFactoryBean interface may explicitly indicate independent instances through its SmartFactoryBean.isPrototype() method. Plain FactoryBean implementations which do not implement this extended interface are simply assumed to always return independent instances if the isSingleton() implementation returns false.

Specified by:
isSingleton in interface FactoryBean<java.lang.Object>
Returns:
whether the exposed object is a singleton
See Also:
FactoryBean.getObject(), SmartFactoryBean.isPrototype()

createCompositeInterface

protected java.lang.Class createCompositeInterface(java.lang.Class[] interfaces)
Create a composite interface Class for the given interfaces, implementing the given interfaces in one single Class.

The default implementation builds a JDK proxy class for the given interfaces.

Parameters:
interfaces - the interfaces to merge
Returns:
the merged interface as Class
See Also:
Proxy.getProxyClass(java.lang.ClassLoader, java.lang.Class...)

Spring Framework