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How do I get java logging output to appear on a single line?
...
As of Java 7, java.util.logging.SimpleFormatter supports getting its format from a system property, so adding something like this to the JVM command line will cause it to print on one line:
-Djava.util.logging.SimpleFormatter.format='%1$tY-%1$tm-%1$td %1$tH:%1$t...
How to round a number to n decimal places in Java
...ode explicitly to handle your issue with the half-even round, then use the format pattern for your required output.
Example:
DecimalFormat df = new DecimalFormat("#.####");
df.setRoundingMode(RoundingMode.CEILING);
for (Number n : Arrays.asList(12, 123.12345, 0.23, 0.1, 2341234.212431324)) {
D...
What is the !! (not not) operator in JavaScript?
I saw some code that seems to use an operator I don't recognize, in the form of two exclamation points, like so: !! . Can someone please tell me what this operator does?
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C#: Looping through lines of multiline string
...l etc :) Having said that, if you do want to do a manual loop, this is the form that I typically prefer over Fredrik's:
using (StringReader reader = new StringReader(input))
{
string line;
while ((line = reader.ReadLine()) != null)
{
// Do something with the line
}
}
This ...
List comprehension: Returning two (or more) items for each item
...cause it does not require recreating the list on every + (thus has O(N) performance rather than O(N^2) performance). I'll still use sum(..., []) when I want a quick one-liner or I'm in a hurry, or when the number of terms being combined is bounded (e.g. <= 10).
– ninjagecko
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When is SQLiteOpenHelper onCreate() / onUpgrade() run?
...hen the database helper constructor is called with a name (2nd param), platform checks if the database exists or not and if the database exists, it gets the version information from the database file header and triggers the right call back
As already explained in the older answer, if the database w...
How to pass a single object[] to a params object[]
...sed to in other languages. params could have been made to only accept one form, and a spread like feature could be added that would benefit the entire language, not just this case. for example, we could force all param calls to be Foo(obj[0], obj[1]), and then have a separate spread operator allow...
Different ways of adding to Dictionary
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The performance is almost a 100% identical. You can check this out by opening the class in Reflector.net
This is the This indexer:
public TValue this[TKey key]
{
get
{
int index = this.FindEntry(key);
if (i...
How to get the top 10 values in postgresql?
...u can use limit
select *
from scores
order by score desc
limit 10
If performance is important (when is it not ;-) look for an index on score.
Starting with version 8.4, you can also use the standard (SQL:2008) fetch first
select *
from scores
order by score desc
fetch first 10 rows only
A...
How do I close a connection early?
...n off output buffering and clear the buffer prior to sending your header information. Example:
<?php
ob_end_clean();
header("Connection: close");
ignore_user_abort(true); // just to be safe
ob_start();
echo('Text the user will see');
$size = ob_get_length();
header("Content-Length: $size");
ob_e...