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What does .class mean in Java?
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And how does Android handle new Intent(this, Activity.class? Will it try to find out class Activity by comparing each class?
– Zhipeng YANG
Sep 21 '16 at 13:28
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Switch statement for string matching in JavaScript
...h");
break;
}
Another approach is to use the String() constructor to convert the resulting array that must have only 1 element (no capturing groups) and whole string must be captured with quanitifiers (.*) to a string. In case of a failure the null object will become a "null" string. Not conve...
Is there a way to take a screenshot using Java and save it to some sort of image?
Simple as the title states: Can you use only Java commands to take a screenshot and save it? Or, do I need to use an OS specific program to take the screenshot and then grab it off the clipboard?
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Extract public/private key from PKCS12 file for later use in SSH-PK-Authentication
...enssl pkcs12 -in pkcs12.pfx -nocerts -nodes | openssl rsa > id_rsa
To convert the private key to a public key:
openssl rsa -in id_rsa -pubout | ssh-keygen -f /dev/stdin -i -m PKCS8
To extract the public key in a format openssh can use:
openssl pkcs12 -in pkcs12.pfx -clcerts -nokeys | openss...
Trimming a huge (3.5 GB) csv file to read into R
So I've got a data file (semicolon separated) that has a lot of detail and incomplete rows (leading Access and SQL to choke). It's county level data set broken into segments, sub-segments, and sub-sub-segments (for a total of ~200 factors) for 40 years. In short, it's huge, and it's not going to fit...
How to run a method every X seconds
I'm developing an Android 2.3.3 application and I need to run a method every X seconds .
8 Answers
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Command prompt won't change directory to another drive
...are enabled CHDIR changes as follows:
The current directory string is converted to use the same case as
the on disk names. So CD C:\TEMP would actually set the current
directory to C:\Temp if that is the case on disk.
CHDIR command does not treat spaces as delimiters, so it is possibl...
What does this symbol mean in JavaScript?
This is a collection of questions that come up every now and then about syntax in JavaScript. This is also a Community Wiki, so everyone is invited to participate in maintaining this list.
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Why are mutable structs “evil”?
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So if you change a copy you are changing only that copy, not the original and not any other copies which might be around.
If your struct is immutable then all automatic copies resulting from being passed by value will be the same.
If you want to change it you have to consciously do it by creating...
Group query results by month and year in postgresql
...request of Radu, I will explain that query:
to_char(date,'Mon') as mon, : converts the "date" attribute into the defined format of the short form of month.
extract(year from date) as yyyy : Postgresql's "extract" function is used to extract the YYYY year from the "date" attribute.
sum("Sales") as...