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Why can't I call read() twice on an open file?
For an exercise I'm doing, I'm trying to read the contents of a given file twice using the read() method. Strangely, when I call it the second time, it doesn't seem to return the file content as a string?
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For files in directory, only echo filename (no path)
How do I go about echoing only the filename of a file if I iterate a directory with a for loop?
5 Answers
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Difference between validate(), revalidate() and invalidate() in Swing GUI
Swing components have multiple methods related to updates of screen layout, in particular:
2 Answers
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Why can I pass 1 as a short, but not the int variable i?
...second Write work but not the last? Is there a way I can allow all 3 of them and detect if it was 1, (int)1 or i passed in? And really why is one allowed but the last? The second being allowed but not the last really blows my mind.
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Why does writeObject throw java.io.NotSerializableException and how do I fix it?
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The fields of your object have in turn their fields, some of which do not implement Serializable. In your case the offending class is TransformGroup. How to solve it?
if the class is yours, make it Serializable
if the class is 3rd party, but you don't need it in the serialized ...
What is PEP8's E128: continuation line under-indented for visual indent?
Just opened a file with Sublime Text (with Sublime Linter) and noticed a PEP8 formatting error that I'd never seen before. Here's the text:
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How to get element by classname or id
I am trying to find the element in html by angularjs.
4 Answers
4
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How to m>cat m>ch SQLServer timeout exceptions
I need to specifically m>cat m>ch SQL server timeout exceptions so that they can be handled differently. I know I could m>cat m>ch the SqlException and then check if the message string Contains "Timeout" but was wondering if there is a better way to do it?
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How to define two fields “unique” as couple
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There is a simple solution for you called unique_together which does exactly what you want.
For example:
class MyModel(models.Model):
field1 = models.CharField(max_length=50)
field2 = models.CharField(max_length=50)
class Meta:
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How to rollback just one step using rake db:migrate
After adding migration files in the db/migrate folder and running rake db:migrate , I want get back to the previous step, I think using VERSION=n is the right way to do that, but I don't know the correct value of n to use. Is there any command to check the current n value?
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