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What's the difference between deadlock and livelock?

... All the content and examples here are from Operating Systems: Internals and Design Principles William Stallings 8º Edition Deadlock: A situation in which two or more processes are unable to proceed because each is waiting ...
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C++11 range based loop: get item by value or reference to const

... @racarate: I cannot comment on the overall speed, and I think nobody can, without profiling it first. Frankly, I wont base my choice on the speed, rather the clarity of the code. If I want immutability, I'd use const for sure. However, whether it would be auto co...
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Using HeapDumpOnOutOfMemoryError parameter for heap dump for JBoss

...mentation has to say: By default the heap dump is created in a file called java_pid.hprof in the working directory of the VM, as in the example above. You can specify an alternative file name or directory with the -XX:HeapDumpPath= option. For example -XX:HeapDumpPath=/disk2/dumps ...
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How do I manage MongoDB connections in a Node.js web application?

...there are multiple database.. should i open a connection for each database all together. If not, Is it OK to open and close when required? – Aman Gupta Oct 25 '16 at 14:19 ...
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What is the !! (not not) operator in JavaScript?

... Partial Obscurity: val.enabled = (userId != 0) ? true : false; // And finally, much easier to understand: val.enabled = (userId != 0); share | improve this answer | follow...
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Possible to do a MySQL foreign key to one of two possible tables?

... What you're describing is called Polymorphic Associations. That is, the "foreign key" column contains an id value that must exist in one of a set of target tables. Typically the target tables are related in some way, such as being instances of some c...
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Modify request parameter with servlet filter

...t that. One solution is to use the HttpServletRequestWrapper class, which allows you to wrap one request with another. You can subclass that, and override the getParameter method to return your sanitized value. You can then pass that wrapped request to chain.doFilter instead of the original request...
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Best way to check if a Data Table has a null value in it

... I usually create an "Extensions" folder in some common library or in my DAL. Create a file called "DataTableExtensions.cs" and add that method. Next you would just add "using Name.Space.Extensions" to your cs files and have access...
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What's “tools:context” in Android layout files?

... That attribute is basically the persistence for the "Associated Activity" selection above the layout. At runtime, a layout is always associated with an activity. It can of course be associated with more than one, but at least one. In the tool, we ...
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Rails: create on has_one association

... First of all, here is how to do what you want: @user = current_user @shop = Shop.create(params[:shop]) @user.shop = @shop Now here's why your version did not work: You probably thought that this might work because if User had a ha...