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What is the difference between up-casting and down-casting with respect to class variable
... a type check and can throw a ClassCastException.
In your case, a cast from a Dog to an Animal is an upcast, because a Dog is-a Animal. In general, you can upcast whenever there is an is-a relationship between two classes.
Downcasting would be something like this:
Animal animal = new Dog();
Dog c...
XPath to find elements that does not have an id or class
How can I get all tr elements without id attribute?
4 Answers
4
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Git commit date
...e date string, is there a Git native way to report the date of a certain commit?
4 Answers
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how to change directory using Windows command line
I'm using cmd.exe (C:\WINDOWS\System32\cmd.exe) and I have to change my current directory to "D:\temp" i.e. temp folder in the D drive.
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Referencing another schema in Mongoose
if I have two schemas like:
3 Answers
3
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Get last result in interactive Python shell
In many symbolic math systems, such as Matlab or Mathematica, you can use a variable like Ans or % to retrieve the last computed value. Is there a similar facility in the Python shell?
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Why does pattern matching in Scala not work with variables?
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What you're looking for is a stable identifier. In Scala, these must either start with an uppercase letter, or be surrounded by backticks.
Both of these would be solutions to your problem:
def mMatch(s: String) = {
val target: String = "a"
s match {
case `target` => p...
How to capture Curl output to a file?
I have a text document that contains a bunch of URLs in this format:
7 Answers
7
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Change directory command in Docker?
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You can run a script, or a more complex parameter to the RUN. Here is an example from a Dockerfile I've downloaded to look at previously:
RUN cd /opt && unzip treeio.zip && mv treeio-master treeio && \
rm -f treeio.zip &amp...
Comment out text in R Markdown (Rmd file)
In an R Markdown ( .Rmd ) file, how do you comment out unused text? I'm not referring to the text in the R code chunk, but the general texts, like % in LaTex for example.
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