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Checking if a string is empty or null in Java [duplicate]
...ge Apache Commons StringUtils.isEmpty(str), which checks for empty strings and handles null gracefully.
Example:
System.out.println(StringUtils.isEmpty("")); // true
System.out.println(StringUtils.isEmpty(null)); // true
Google Guava also provides a similar, probably easier-to-read method: Stri...
How to sign an android apk file
... get stuck with after you work through it, I'd suggest:
https://developer.android.com/studio/publish/app-signing.html
Okay, a small overview without reference or eclipse around, so leave some space for errors, but it works like this
Open your project in eclipse
Press right-mouse - > tools (an...
Optimise PostgreSQL for fast testing
.... For example, PostgreSQL 9.2 significantly improves the speed of TRUNCATE and of course adds index-only scans. Even minor releases should always be followed; see the version policy.
Don'ts
Do NOT put a tablespace on a RAMdisk or other non-durable storage.
If you lose a tablespace the whole datab...
SQL Server String or binary data would be truncated
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You will need to post the table definitions for the source and destination tables for us to figure out where the issue is but the bottom line is that one of your columns in the source table is bigger than your destination columns. It could be that you are changing formats in a way y...
How to remove/ignore :hover css style on touch devices
...ur website via touch device. Because the :hover CSS does not make sense, and it can even be disturbing if a tablet triggers it on click/tap because then it might stick until the element loses focus. To be honest, I don't know why touch devices feel the need to trigger :hover in first place - but...
Selecting and manipulating CSS pseudo-elements such as ::before and ::after using jQuery
... there any way to select/manipulate CSS pseudo-elements such as ::before and ::after (and the old version with one semi-colon) using jQuery?
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Single script to run in both Windows batch and Linux Bash?
...rite a single script file which executes in both Windows (treated as .bat) and Linux (via Bash)?
11 Answers
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Recommended SQL database design for tags or tagging [closed]
...rd of a few ways to implement tagging; using a mapping table between TagID and ItemID (makes sense to me, but does it scale?), adding a fixed number of possible TagID columns to ItemID (seems like a bad idea), Keeping tags in a text column that's comma separated (sounds crazy but could work). I've e...
test if event handler is bound to an element in jQuery [duplicate]
Is it possible to determine whether an element has a click handler, or a change handler, or any kind of event handler bound to it using jQuery?
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Should functions return null or an empty object?
...g data from functions. Is it better to return a Null or an empty object? And why should one do one over the other?
31 Ans...