public abstract class AbstractLazyCreationTargetSource extends java.lang.Object implements TargetSource
TargetSource implementation that will
lazily create a user-managed object.
Creation of the lazy target object is controlled by the user by implementing
the createObject() method. This TargetSource will invoke
this method the first time the proxy is accessed.
Useful when you need to pass a reference to some dependency to an object but you don't actually want the dependency to be created until it is first used. A typical scenario for this is a connection to a remote resource.
isInitialized(),
createObject()| Modifier and Type | Field and Description |
|---|---|
protected Log |
logger
Logger available to subclasses
|
| Constructor and Description |
|---|
AbstractLazyCreationTargetSource() |
| Modifier and Type | Method and Description |
|---|---|
protected abstract java.lang.Object |
createObject()
Subclasses should implement this method to return the lazy initialized object.
|
java.lang.Object |
getTarget()
Returns the lazy-initialized target object,
creating it on-the-fly if it doesn't exist already.
|
java.lang.Class<?> |
getTargetClass()
This default implementation returns
null if the
target is null (it is hasn't yet been initialized),
or the target class if the target has already been initialized. |
boolean |
isInitialized()
Return whether the lazy target object of this TargetSource
has already been fetched.
|
boolean |
isStatic()
Will all calls to
TargetSource.getTarget() return the same object? |
void |
releaseTarget(java.lang.Object target)
Release the given target object obtained from the
TargetSource.getTarget() method, if any. |
protected final Log logger
public boolean isInitialized()
public java.lang.Class<?> getTargetClass()
null if the
target is null (it is hasn't yet been initialized),
or the target class if the target has already been initialized.
Subclasses may wish to override this method in order to provide
a meaningful value when the target is still null.
getTargetClass in interface TargetClassAwaregetTargetClass in interface TargetSourceTargetSourceisInitialized()public boolean isStatic()
TargetSourceTargetSource.getTarget() return the same object?
In that case, there will be no need to invoke TargetSource.releaseTarget(Object),
and the AOP framework can cache the return value of TargetSource.getTarget().
isStatic in interface TargetSourcetrue if the target is immutableTargetSource.getTarget()public java.lang.Object getTarget()
throws java.lang.Exception
getTarget in interface TargetSourcenull if there is no actual target instancejava.lang.Exception - if the target object can't be resolvedcreateObject()public void releaseTarget(java.lang.Object target)
throws java.lang.Exception
TargetSourceTargetSource.getTarget() method, if any.releaseTarget in interface TargetSourcetarget - object obtained from a call to TargetSource.getTarget()java.lang.Exception - if the object can't be releasedprotected abstract java.lang.Object createObject()
throws java.lang.Exception
java.lang.Exception - if creation failed