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Environment variable to control java.io.tmpdir?
... there's a way to do this other than on Windows.
On Windows, OpenJDK's get_temp_directory() function makes a Win32 API call to GetTempPath(); this is how on Windows, Java reflects the value of the TMP environment variable.
On Linux and Solaris, the same get_temp_directory() functions return a stat...
How to find the Windows version from the PowerShell command line
...t is client or server Windows, nor the name of the version.
Use WMI's Win32_OperatingSystem class (always single instance), for example:
(Get-WmiObject -class Win32_OperatingSystem).Caption
will return something like
Microsoft® Windows Server® 2008 Standard
...
iOS start Background Thread
...ou'd probably be better off using Grand Central Dispatch, though:
dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
[self getResultSetFromDB:docids];
});
GCD is a newer technology, and is more efficient in terms of memory overhead and lines of code.
Updated w...
@RequestParam vs @PathVariable
...re interesting annotation:
@MatrixVariable
http://localhost:8080/spring_3_2/matrixvars/stocks;BT.A=276.70,+10.40,+3.91;AZN=236.00,+103.00,+3.29;SBRY=375.50,+7.60,+2.07
And the Controller method for it
@RequestMapping(value = "/{stocks}", method = RequestMethod.GET)
public String showPortfo...
What does “abstract over” mean?
...mbers under a single symbol ns:
def sumOf(ns: List[Int]) = ns.foldLeft(0)(_ + _)
And we don't particularly care that it's a List either. List is a specific type constructor (takes a type and returns a type), but we can abstract over the type constructor by specifying which essential characteristi...
How do I test a file upload in rails?
...ing to make it available on SO.
The rails framework has a function fixture_file_upload (Rails 2 Rails 3, Rails 5), which will search your fixtures directory for the file specified and will make it available as a test file for the controller in functional testing. To use it:
1) Put your file to be ...
How To Change DataType of a DataColumn in a DataTable?
...newType)
{
using (DataColumn dc = new DataColumn(columnName + "_new", newType))
{
// Add the new column which has the new type, and move it to the ordinal of the old column
int ordinal = dt.Columns[columnName].Ordinal;
dt.Columns.Add(dc);
...
What is the JavaScript convention for no operation?
...noop = ()=>{};
const noopProto = Function.prototype;
function test (_noop, iterations) {
const before = performance.now();
for(let i = 0; i < iterations; i++) _noop();
const after = performance.now();
const elapsed = after - before;
console.info(`${elapsed.toFixed(...
How much is the overhead of smart pointers compared to normal pointers in C++?
...
std::unique_ptr has memory overhead only if you provide it with some non-trivial deleter.
std::shared_ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constru...
How do I recursively delete a directory and its entire contents (files + sub dirs) in PHP?
...mdir contains a decent implementation:
function rrmdir($dir) {
if (is_dir($dir)) {
$objects = scandir($dir);
foreach ($objects as $object) {
if ($object != "." && $object != "..") {
if (is_dir($dir. DIRECTORY_SEPARATOR .$object) && !is_link($dir."/"...