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What is the difference between CascadeType.REMOVE and orphanRemoval in JPA?
...s address;
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Orphan Removal
JPA 2 supports an additional and more aggressive remove cascading mode
which can be specified using the orphanRemoval element of the
@OneToOne and @OneToMany annotations:
@Entity
class Employee {
:
@OneToOne(orphanRemoval=true)
private ...
Timer & TimerTask versus Thread + sleep in Java
...k is that it expresses your intention much better (i.e. code readability), and it already has the cancel() feature implemented.
Note that it can be written in a shorter form as well as your own example:
Timer uploadCheckerTimer = new Timer(true);
uploadCheckerTimer.scheduleAtFixedRate(
new Tim...
Should I declare Jackson's ObjectMapper as a static field?
...
Yes, that is safe and recommended.
The only caveat from the page you referred is that you can't be modifying configuration of the mapper once it is shared; but you are not changing configuration so that is fine. If you did need to change conf...
How do I use Django templates without the rest of Django?
...Django-based web site. How do I use it without having a settings.py file (and others) and having to set the DJANGO_SETTINGS_MODULE environment variable?
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How to detect duplicate values in PHP array?
...he presence of duplicate values, then count the number of duplicate values and out put the results. For example, given the following array:
...
Get Substring between two characters using javascript
...string from within a larger string where it get everything inbetween a ':' and a ';'.
16 Answers
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mkdir's “-p” option
...oes in Unix. I used it for a lab assignment while creating a subdirectory and then another subdirectory within that one. It looked like this:
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Declaring variables inside a switch statement [duplicate]
I saw a few answers to this issue, and I get it — you can't declare and assign variables inside a switch . But I'm wondering if the following is correct at throwing an error saying
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Implementing comparison operators via 'tuple' and 'tie', a good idea?
(Note: tuple and tie can be taken from Boost or C++11.)
When writing small structs with only two elements, I sometimes tend to choose a std::pair , as all important stuff is already done for that datatype, like operator< for strict-weak-ordering.
The downsides though are the pretty much us...
Strip HTML from strings in Python
...e, I'm trying to find a way to only show the contents of each HTML element and not the formatting itself. If it finds '<a href="whatever.com">some text</a>' , it will only print 'some text', '<b>hello</b>' prints 'hello', etc. How would one go about doing this?
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