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Eclipse says: “Workspace in use or cannot be created, chose a different one.” How do I unlock a work
...e cause of the “Workspace in use or cannot be created, chose a different one” issue is that the real path to your workspace may have changed.
In my case, the real location of the workspace had changed, but I had used a symlink to make it look like it was in the same location. I saw errors in l...
What's the difference between SoftReference and WeakReference in Java?
...renced by a SoftReference if there isn't pressure on the available memory. One detail: the policy for the "-client" and "-server" JRE's are different: the -client JRE tries to keep your footprint small by preferring to clear SoftReferences rather than expand the heap, whereas the -server JRE tries t...
Class does not implement its superclass's required members
... the point of this class. This class simply cannot be instantiated without one. It is going to analyze the collection and initialize a dozen instance variables. That is the whole point of this being the one and only designated initializer! Thus, init(coder:) has no meaningful (or even meaningless) M...
How to find the duration of difference between two dates in java?
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This answer ignores time zones which define the beginning and ending of days. This answer ignores Daylight Saving Time and other anomalies that mean a day is not always 24 hours in length. See the correct answers that use either Joda-Time or java.time...
Why did my Git repo enter a detached HEAD state?
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Any checkout of a commit that is not the name of one of your branches will get you a detached HEAD. A SHA1 which represents the tip of a branch still gives a detached HEAD. Only a checkout of a local branch name avoids that mode.
See committing with a detached HEAD
Whe...
Which Radio button in the group is checked?
...t be necessary. When you check a different RadioButton then it knows which one to uncheck… so it should know which is checked. How do I pull that information without doing a lot of if statements (or a switch).
...
Eloquent Collection: Counting and Detect Empty
...model, or null otherwise. This is useful if you need or are expecting only one result from the database.
$result = Model::where(...)->first();
if ($result) { ... }
Notes / References
->first() http://laravel.com/api/4.2/Illuminate/Database/Eloquent/Collection.html#method_first
isEmpty() h...
Benefits of prototypal inheritance over classical?
...gging my feet all these years and decided to learn JavaScript "properly". One of the most head-scratching elements of the languages design is it's implementation of inheritance. Having experience in Ruby, I was really happy to see closures and dynamic typing; but for the life of me can't figure ou...
How to Truncate a string in PHP to the word closest to a certain number of characters?
.... It splits the texts in multiple lines such that the maximum width is the one you specified, breaking at word boundaries. After splitting, you simply take the first line:
substr($string, 0, strpos(wordwrap($string, $your_desired_width), "\n"));
One thing this oneliner doesn't handle is the case ...
What algorithm can be used for packing rectangles of different sizes into the smallest rectangle pos
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The quick and dirty first pass solution is always a great one to start with, as a comparison if nothing else.
Greedy placement from large to small.
Put the largest rectangle remaining into your packed area. If it can't fit anywhere, place it in a place that extends the pack region...