大约有 45,000 项符合查询结果(耗时:0.0619秒) [XML]
javax.faces.application.ViewExpiredException: View could not be restored
...alidate() in server, or due a server specific bug with session cookies as known in WildFly), then the serialized view state is not available anymore in the session and the enduser will get this exception. To understand the working of the session, see also How do servlets work? Instantiation, session...
java.sql.SQLException: - ORA-01000: maximum open cursors exceeded
...e theory behind cursors and how JDBC should be used. If you don't need to know the background, you can skip this and go straight to 'Eliminating Leaks'.
What is a cursor?
A cursor is a resource on the database that holds the state of a query, specifically the position where a reader is in a Result...
How to handle Handler messages when activity/fragment is paused
... /**
* Store the message if we have been paused, otherwise handle it now.
*
* @param msg Message to handle.
*/
@Override
public final synchronized void handleMessage(Message msg) {
if (activity == null) {
final Message msgCopy = new Message();
...
Dependency Inject (DI) “friendly” library
...eed a short-lived object, or to construct the dependency based on a value known only at run-time.
See this for more information.
Compose only at the Last Responsible Moment
Keep objects decoupled until the very end. Normally, you can wait and wire everything up in the application's entry point. T...
How do servlets work? Instantiation, sessions, shared variables and multithreading
...afety
That said, your major concern is possibly thread safety. You should now know that servlets and filters are shared among all requests. That's the nice thing about Java, it's multithreaded and different threads (read: HTTP requests) can make use of the same instance. It would otherwise be too e...
MySQL order by before group by
...publish', post_type='post', post_author='user A', post_date='2012-12-31')
Now, when you order the results of the grouping by post_date, you get the data you wanted.
SELECT wp_posts.*
FROM wp_posts
WHERE wp_posts.post_status='publish' AND wp_posts.post_type='post'
GROUP BY wp_posts.post_author DESC...
In what cases could `git pull` be harmful?
...it of a (fake) linear history
Not cleaning up branches is good. Each repo knows what it wants to hold. Git has no notion of master-slave relationships.
share
|
improve this answer
|
...
LINQ with groupby and count
... UserInfo objects. In the second occurrence n is of type Grouping, because now it's a list of Grouping objects.
Groupings have extension methods like .Count(), .Key() and pretty much anything else you would expect. Just as you would check .Lenght on a string, you can check .Count() on a group.
...
Why it's not possible to use regex to parse HTML/XML: a formal explanation in layman's terms
... closing tags match a previous opening tag. To understand it, you need to know which element is being closed. Without any means to "remember" what opening tags you've seen, no chance.
Note however that most "regex" libraries actually permit more than just the strict definition of regular expression...
Are there any open source C libraries with common data structures? [closed]
...
And now it appears to be: github.com/davinash/cstl It hasn't been updated since 2012 though.
– domen
Jul 24 '17 at 9:24
...
