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Get JSF managed bean by name in any Servlet related class

... In a servlet based artifact, such as @WebServlet, @WebFilter and @WebListener, you can grab a "plain vanilla" JSF @ManagedBean @RequestScoped by: Bean bean = (Bean) request.getAttribute("beanName"); and @ManagedBean @SessionScoped by: Bean bean = (Bean) request.getSession().getAttribu...
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What is the equivalent of “none” in django templates?

... None, False and True all are available within template tags and filters. None, False, the empty string ('', "", """""") and empty lists/tuples all evaluate to False when evaluated by if, so you can easily do {% if profile.user.first_nam...
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Where is the list of predefined Maven properties

... mvn help:effective-pom stands as a great tool for discovering properties available. maven.apache.org/plugins/maven-help-plugin/… – Peter Kahn Jul 4 '16 at 15:01 ...
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How to make a vertical line in HTML

...a <div> around the markup where you want the line to appear to next, and use CSS to style it: .verticalLine { border-left: thick solid #ff0000; } <div class="verticalLine"> some other content </div> ...
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Application Crashes With “Internal Error In The .NET Runtime”

...ce might be using. Suspect environmental problems if there is no obvious candidate, misbehaving malware scanners are notorious. If it repeats very poorly then suspect hardware problems like soft RAM errors. share ...
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What is the difference between String.Empty and “” (empty string)?

In .NET, what is the difference between String.Empty and "" , and are they interchangable, or is there some underlying reference or Localization issues around equality that String.Empty will ensure are not a problem? ...
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Deleting all files in a directory with Python

... Via os.listdir and os.remove: import os filelist = [ f for f in os.listdir(mydir) if f.endswith(".bak") ] for f in filelist: os.remove(os.path.join(mydir, f)) Or via glob.glob: import glob, os, os.path filelist = glob.glob(os.path...
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Comparing two dataframes and getting the differences

...This approach, df1 != df2, works only for dataframes with identical rows and columns. In fact, all dataframes axes are compared with _indexed_same method, and exception is raised if differences found, even in columns/indices order. If I got you right, you want not to find changes, but symmetric d...
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SQL join on multiple columns in same tables

... Join like this: ON a.userid = b.sourceid AND a.listid = b.destinationid; share | improve this answer | follow | ...
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How to set a timer in android

What is the proper way to set a timer in android in order to kick off a task (a function that I create which does not change the UI)? Use this the Java way: http://docs.oracle.com/javase/1.5.0/docs/api/java/util/Timer.html ...