org.springframework.beans
Class CachedIntrospectionResults

java.lang.Object
  org.springframework.beans.CachedIntrospectionResults

public class CachedIntrospectionResults
extends Object

Internal class that caches JavaBeans PropertyDescriptor information for a Java class. Not intended for direct use by application code.

Necessary as Introspector.getBeanInfo() in JDK 1.3 will return a new deep copy of the BeanInfo every time we ask for it. We take the opportunity to cache property descriptors by method name for fast lookup. Furthermore, we do our own caching of descriptors here, rather than rely on the JDK's system-wide BeanInfo cache (to avoid leaks on ClassLoader shutdown).

Information is cached statically, so we don't need to create new objects of this class for every JavaBean we manipulate. Hence, this class implements the factory design pattern, using a private constructor and a static forClass(Class) factory method to obtain instances.

Since:

05 May 2001

Author:

Rod Johnson, Juergen Hoeller

See Also:

acceptClassLoader(ClassLoader), clearClassLoader(ClassLoader), forClass(Class)

Method Summary

static void	acceptClassLoader(ClassLoader classLoader) Accept the given ClassLoader as cache-safe, even if its classes would not qualify as cache-safe in this CachedIntrospectionResults class.
static void	clearClassLoader(ClassLoader classLoader) Clear the introspection cache for the given ClassLoader, removing the introspection results for all classes underneath that ClassLoader, and deregistering the ClassLoader (and any of its children) from the acceptance list.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

acceptClassLoader

public static void acceptClassLoader(ClassLoader classLoader)

Accept the given ClassLoader as cache-safe, even if its classes would not qualify as cache-safe in this CachedIntrospectionResults class.

This configuration method is only relevant in scenarios where the Spring classes reside in a 'common' ClassLoader (e.g. the system ClassLoader) whose lifecycle is not coupled to the application. In such a scenario, CachedIntrospectionResults would by default not cache any of the application's classes, since they would create a leak in the common ClassLoader.

Any acceptClassLoader call at application startup should be paired with a clearClassLoader(java.lang.ClassLoader) call at application shutdown.

Parameters:

classLoader - the ClassLoader to accept

clearClassLoader

public static void clearClassLoader(ClassLoader classLoader)

Clear the introspection cache for the given ClassLoader, removing the introspection results for all classes underneath that ClassLoader, and deregistering the ClassLoader (and any of its children) from the acceptance list.

Parameters:

classLoader - the ClassLoader to clear the cache for