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Check if null Boolean is true results in exception
...s any other object.
In your particular case, your Boolean is null and the if statement triggers an implicit conversion to boolean that produces the NullPointerException. You may need instead:
if(bool != null && bool) { ... }
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Java, Simplified check if int array contains int
...ally my mate has been saying that I could make my code shorter by using a different way of checking if an int array contains an int, although he won't tell me what it is :P.
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'UserControl' constructor with parameters in C#
...me crazy, but I'm the type of guy that likes constructors with parameters (if needed), as opposed to a constructor with no parameters followed by setting properties. My thought process: if the properties are required to actually construct the object, they should go in the constructor. I get two adva...
Django. Override save for model
Before saving model I'm re-size a picture. But how can I check if new picture added or just description updated, so I can skip rescaling every time the model is saved?
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When to choose checked and unchecked exceptions
..., you try reading a file but someone deletes it between the time you check if it exists and the time the read operation begins. By declaring a checked exception, you are telling the caller to anticipate this failure.
Reasonable to recover from: There is no point telling callers to anticipate excepti...
How can I do something like a FlowLayout in Android?
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If you watch the talk I gave at the Devoxx University day (available on parleys.com) you will learn how to do it yourself. During the talk I wrote a FlowLayout implementation live on stage to show how simple it is to write cu...
python ? (conditional/ternary) operator for assignments [duplicate]
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Python has such an operator:
variable = something if condition else something_else
Alternatively, although not recommended (see @karadoc's comment):
variable = (condition and something) or something_else
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Only mkdir if it does not exist [duplicate]
...ld send a message to the user and ask for input, abort, or do other things if [[ -e dir && ! -d dir ]] is valid.
– konsolebox
Sep 4 '13 at 22:17
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C# 通过代码安装、卸载、启动、停止服务 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...ceName);
string dispName = string.Empty;
if (!ServiceIsExisted(serviceName, ref dispName))
{
// Install Service
AssemblyInstaller myAssemblyInstaller = new AssemblyInstaller();
myAssembl...