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How do I get the object if it exists, or None if it does not exist?
When I ask the model manager to get an object, it raises DoesNotExist when there is no matching object.
18 Answers
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Why should I use a pointer rather than the object itself?
I'm coming from a Java background and have started working with objects in C++. But one thing that occurred to me is that people often use pointers to objects rather than the objects themselves, for example this declaration:
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Sort a Map by values
I am relatively new to Java, and often find that I need to sort a Map<Key, Value> on the values.
58 Answers
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JavaScript code to stop form submission
One way to stop form submission is to return false from your JavaScript function.
12 Answers
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How to create directory automatically on SD card
I'm trying to save my file to the following location
FileOutputStream fos = new FileOutputStream("/sdcard/Wallpaper/"+fileName);
but I'm getting the exception java.io.FileNotFoundException
However, when I put the path as "/sdcard/" it works.
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indexOf method in an object array?
What's the best method to get the index of an array which contains objects?
27 Answers
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Downloading Java JDK on Linux via wget is shown license page instead
When I try to download Java from Oracle I instead end up downloading a page telling me that I need agree to the OTN license terms.
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How do I create a unique ID in Java? [duplicate]
I'm looking for the best way to create a unique ID as a String in Java.
11 Answers
11
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PHP Warning: PHP Startup: Unable to load dynamic library
I run a PHP script and get this error:
19 Answers
19
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How to test which port MySQL is running on and whether it can be connected to?
I have installed MySQL and even logged in there as a user.
13 Answers
13
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