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What can be the reasons of connection refused errors?
... its backlog of pending connections is full.
A firewall between the client and server is blocking access (also check local firewalls).
After checking for firewalls and that the port is open, use telnet to connect to the ip/port to test connectivity. This removes any potential issues from your appl...
Adding devices to team provisioning profile
... can't hook it up to my computer so Xcode can't add the UDID to my devices and to the team provisioning profile. Is there a way to add it manually to the team provisioning profile, I can't figure out how to edit it. Also when I add the device in my provisioning portal it doesn't get added to my te...
How do I write JSON data to a file?
...
You forgot the actual JSON part - data is a dictionary and not yet JSON-encoded. Write it like this for maximum compatibility (Python 2 and 3):
import json
with open('data.json', 'w') as f:
json.dump(data, f)
On a modern system (i.e. Python 3 and UTF-8 support), you can wr...
JavaScript data grid for millions of rows [closed]
...s set to the total height of all the rows. The rows are still being added and removed as the user is scrolling, but the scrolling itself is done by the browser. That allows it to be very fast yet smooth (onscroll events are notoriously slow). The caveat is that there are bugs/limits in the browse...
Use of def, val, and var in scala
... new Person("Kumar",12) . If I use var or val the output is 20 . I understand the default is val in scala. This:
6 Answers...
Why does my application spend 24% of its life doing a null check?
I've got a performance critical binary decision tree, and I'd like to focus this question on a single line of code. The code for the binary tree iterator is below with the results from running performance analysis against it.
...
How to override equals method in Java
... in Java. I have a class People which basically has 2 data fields name and age . Now I want to override equals method so that I can check between 2 People objects.
...
What's the difference between Thread start() and Runnable run()
...ing) thread. No thread creation.
R1 r1 = new R1();
R2 r2 = new R2();
r1 and r2 are just two different objects of classes that implement the Runnable interface and thus implement the run() method. When you call r1.run() you are executing it in the current thread.
Second example: Two separate thr...
ROW_NUMBER() in MySQL
...
SELECT t0.col3
FROM table AS t0
LEFT JOIN table AS t1 ON t0.col1=t1.col1 AND t0.col2=t1.col2 AND t1.col3>t0.col3
WHERE t1.col1 IS NULL;
“Get the rows in the table for which no other row with matching col1,col2 has a higher col3.” (You will notice this and most other groupwise-maximum solu...
How to use single storyboard uiviewcontroller for multiple subclass
...interface but with root view controller of class SpecificViewController1 and SpecificViewController2 which are subclasses of BasicViewController .
Those 2 view controllers would have the same functionality and interface except for the IBAction method.
It would be like the following:
...