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Difference between null and empty (“”) Java String
... can still invoke methods or functions on it like
a.length()
a.substring(0, 1)
and so on.
If the String equals null, like b, Java would throw a NullPointerException if you tried invoking, say:
b.length()
If the difference you are wondering about is == versus equals, it's this:
== compares ...
Removing duplicate rows in Notepad++
...
answered Oct 18 '10 at 10:46
Colin PickardColin Pickard
42.2k1111 gold badges9191 silver badges142142 bronze badges
...
How to clear variables in ipython?
...
208
%reset seems to clear defined variables.
...
What is the curiously recurring template pattern (CRTP)?
... You can write
int main()
{
Apple a1;
Apple a2;
a1.size = 10;
a2.size = 10;
if(a1 == a2) //the compiler won't complain!
{
}
}
This could seem that you would write less if you just wrote operator == for Apple, but imagine that the Equality template would provide not...
How can I know if a process is running?
...ocess[] pname = Process.GetProcessesByName("notepad");
if (pname.Length == 0)
MessageBox.Show("nothing");
else
MessageBox.Show("run");
You can loop all process to get the ID for later manipulation:
Process[] processlist = Process.GetProcesses();
foreach(Process theprocess in processlist){
...
Where do I find the bashrc file on Mac?
...'
– Michael Dimmitt
Feb 4 '17 at 16:05
...
How can I reliably get an object's address when operator& is overloaded?
...
102
Update: in C++11, one may use std::addressof instead of boost::addressof.
Let us first copy ...
Facebook database design?
...
90
Keep a friend table that holds the UserID and then the UserID of the friend (we will call it Fri...
Tick symbol in HTML/XHTML
... have glyphs for all the code points.
Try the following characters:
☐ (0x2610 in Unicode hexadecimal [HTML decimal: ☐]): an empty (unchecked) checkbox
☑ (0x2611 [HTML decimal: ☑]): the checked version of the previous checkbox
✓ (0x2713 [HTML decimal: ✓])
✔ (0...
Free space in a CMD shell
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edited Nov 16 '08 at 11:14
answered Nov 16 '08 at 11:09
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