大约有 6,000 项符合查询结果（耗时：0.0165秒） [XML]
Why is creating a Thread said to be expensive?
...tem calls need to be made to create / register the native thread with the host OS.
Descriptors need to be created, initialized and added to JVM-internal data structures.
It is also expensive in the sense that the thread ties down resources as long as it is alive; e.g. the thread stack, any objects...
How to create full compressed tar file using Python?
... a .tar.gz (aka .tgz) for an entire directory tree:
import tarfile
import os.path
def make_tarfile(output_filename, source_dir):
with tarfile.open(output_filename, "w:gz") as tar:
tar.add(source_dir, arcname=os.path.basename(source_dir))
This will create a gzipped tar archive contain...
What is the difference between ExecuteScalar, ExecuteReader and ExecuteNonQuery?
...a generated id after inserting.
INSERT INTO my_profile (Address) VALUES ('123 Fake St.');
SELECT CAST(scope_identity() AS int)
ExecuteReader gives you a data reader
back which will allow you to read all
of the columns of the results a row
at a time.
An example would be pulling profile informati...
How can I tell if I'm running in 64-bit JVM or 32-bit JVM (from within a program)?
...the bitness of this JVM with:
System.getProperty("sun.arch.data.model");
Possible results are:
"32" – 32-bit JVM
"64" – 64-bit JVM
"unknown" – Unknown JVM
As described in the HotSpot FAQ:
When writing Java code, how do I distinguish between 32 and 64-bit operation?
There's no public API th...
How to get current CPU and RAM usage in Python?
...e ps, top and Windows task manager.
It currently supports Linux, Windows, OSX, Sun Solaris, FreeBSD, OpenBSD and NetBSD, both 32-bit and 64-bit architectures, with Python versions from 2.6 to 3.5 (users of Python 2.4 and 2.5 may use 2.1.3 version).
Some examples:
#!/usr/bin/env python
import psut...
How to test equality of Swift enums with associated values
...{
case Name(String)
case Number(Int)
}
let t1 = SimpleToken.Number(123)
let t2 = SimpleToken.Number(123)
Before Swift 4.1
As others have noted, Swift doesn't synthesize the necessary equality operators automatically. Let me propose a cleaner (IMHO) implementation, though:
enum SimpleToke...
How can I change Mac OS's default Java VM returned from /usr/libexec/java_home
...dkhome="`/usr/libexec/java_home -v '1.7*'`"
and this will force it to choose Java 7 instead of 8.
share
|
improve this answer
|
follow
|
...
How can I install Apache Ant on Mac OS X?
...
Ant is already installed on some older versions of Mac OS X, so you should run ant -version to test if it is installed before attempting to install it.
If it is not already installed, then your best bet is to install Homebrew (brew install ant) or MacPorts (sudo port install ap...
How do you Encrypt and Decrypt a PHP String?
...xample I want to pass a GET parameter from page to page, let's say prod_id=123 but I just do not want to make 123 readable for everybody, however even if they could read it, it won't be a problem. An attacker being able to replace the 123 to a custom value won't cause any harm, he/she will only be a...
Can a CSV file have a comment?
... I have more often seen and used: #Csv/Version 1.9 Time,ValueA,ValueB 0.0, 123, 456 0.1, 123, 349
– Crog
Aug 25 at 8:31
add a comment
|
...