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Open Source Java Profilers [closed]
What can you guys recommend to use with Java?
12 Answers
12
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Postgresql aggregate array
...
Use array_agg: http://www.sqlfiddle.com/#!1/5099e/1
SELECT s.name, array_agg(g.Mark) as marks
FROM student s
LEFT JOIN Grade g ON g.Student_id = s.Id
GROUP BY s.Id
By the way, if you are using Postgres 9.1, you don't need to repeat the...
What are the effects of exceptions on performance in Java?
...st too long to post here. So let me summarize here and refer you to http://www.fuwjax.com/how-slow-are-java-exceptions/ for the gritty details.
The real question here is not "How slow are 'failures reported as exceptions' compared to 'code that never fails'?" as the accepted response might have you...
RabbitMQ message size and types
... DB.
You might also want to read up on their performance measures:
http://www.rabbitmq.com/blog/2012/04/17/rabbitmq-performance-measurements-part-1/
http://www.rabbitmq.com/blog/2012/04/25/rabbitmq-performance-measurements-part-2/
Queues are pretty light weight, you will most likely be limited by t...
Database Structure for Tree Data Structure
...ructure. You can get the idea from there.(For more information see: http://www.postgresql.org/docs/9.0/static/ltree.html)
In common LDAP is used to organize records in hierarchical structure.
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Intellij IDEA generate for-each/for keyboard shortcut
...lt+J or Ctrl+Alt+J
Choose Iterate Iterable from the dropdown (i)
https://www.jetbrains.com/phpstorm/help/creating-code-constructs-using-surround-templates.html
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How do I loop through or enumerate a JavaScript object?
... sure that the key you get is an actual property of an object, and doesn't come from the prototype.
Here is the snippet:
var p = {
"p1": "value1",
"p2": "value2",
"p3": "value3"
};
for (var key in p) {
if (p.hasOwnProperty(key)) {
console.log(key + " -> " + p...
“java.lang.OutOfMemoryError : unable to create new native Thread”
...threads the operating system will allow your JVM to use.
This is an uncommon problem, because you rarely need that many. Do you have a lot of unconditional thread spawning where the threads should but doesn't finish?
You might consider rewriting into using Callable/Runnables under the contr...
Git / Bower Errors: Exit Code # 128 & Failed connect
...ere I was trying this. So no SSH to github :( I can say that I did run the command from the (git) project folder...if that makes any diff.
– demaniak
Oct 21 '14 at 16:03
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iTerm 2: How to set keyboard shortcuts to jump to beginning/end of line?
...ile Shortcut Keys
FOR ACTION SEND
⌘← "SEND HEX CODE" 0x01
⌘→ "SEND HEX CODE" 0x05
⌥← "SEND ESC SEQ" b
⌥→ "SEND ESC SEQ" f
Here is a visual for those who need it
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