org.apache.derby.impl.store.raw.data
Class RemoveFile
java.lang.Object
org.apache.derby.impl.store.raw.data.RemoveFile
- All Implemented Interfaces:
- java.security.PrivilegedExceptionAction, Serviceable
final class RemoveFile
- extends java.lang.Object
- implements Serviceable, java.security.PrivilegedExceptionAction
Method Summary |
int |
performWork(ContextManager context)
Do whatever it is that you want the daemon to do for you. |
java.lang.Object |
run()
|
boolean |
serviceASAP()
If this work should be done as soon as possible, then return true. |
boolean |
serviceImmediately()
File deletion is a quick operation and typically releases substantial
amount of space very quickly, this work should be done on the
user thread. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
fileToGo
private final StorageFile fileToGo
RemoveFile
RemoveFile(StorageFile fileToGo)
performWork
public int performWork(ContextManager context)
throws StandardException
- Description copied from interface:
Serviceable
- Do whatever it is that you want the daemon to do for you. There may be
multiple daemon objects on different thread calling performWork at the
same time.
The DaemonService will always call performWork with a context manager
set up. the DaemonService will clean up the context if an exception is
thrown. However, it is up to performWork to manage its own
transaction. If you start a transaction in performWork, you
must commit or abort it at the end. You may leave the
transaction open so that other serviceable may use the transaction and
context without starting a new one. On the same token, there may
already be an opened transaction on the context. Serviceable
performWork should always check the state of the context before use.
A Serviceable object should be well behaved while it is performing the
daemon work, i.e., it should not take too many resources or hog the CPU
for too long or deadlock with anyone else.
- Specified by:
performWork
in interface Serviceable
- Parameters:
context
- the contextManager set up by the DaemonService. There
may or may not be the necessary context on it, depending on which other
Serviceable object it has done work for.
- Returns:
- the return status is only significant if the Serviceable client
was enqueued instead of subscribed. For subscribed client, the return
status is ignored. For enqueue client, it returns DONE or REQUEUE. If
a REQUEUEd is returned, it would be desirable if this should not be
serviceASAP, although no harm is done if this still maintains that this
should be serviced ASAP ...
- Throws:
StandardException
- Standard Derby exception policy
MT - depends on the work. Be wary of multiple DaemonService thread
calling at the same time if you subscribe or enqueue multiple times.
serviceASAP
public boolean serviceASAP()
- Description copied from interface:
Serviceable
- If this work should be done as soon as possible, then return true.
If it doesn't make any difference if it is done sooner rather than
later, then return false.
The difference is whether or not the daemon service will be notified to
work on this when this work is enqueued or subscribed, in case the
serviceable work is put together but not sent to the daemon service
directly, like in post commit processing
MT - MT safe
- Specified by:
serviceASAP
in interface Serviceable
serviceImmediately
public boolean serviceImmediately()
- File deletion is a quick operation and typically releases substantial
amount of space very quickly, this work should be done on the
user thread.
- Specified by:
serviceImmediately
in interface Serviceable
- Returns:
- true, this work needs to done on user thread.
run
public java.lang.Object run()
throws StandardException
- Specified by:
run
in interface java.security.PrivilegedExceptionAction
- Throws:
StandardException
Apache Derby V10.6 Internals - Copyright © 2004,2007 The Apache Software Foundation. All Rights Reserved.