This is similar to the previous blog post except this is more direct. The answer is “Yes” for all tested languages except C and C++. This may seem trivial until you meet a situation where the same original object is shared across requests/sessions, like a public static variable in Java or an incorrectly scoped Javascript …
As per title, ran this across various languages. Results are mixed, but IMHO, it seems unsafe to design your functions/methods this way. It would be better to pass in the object, compute the changes without modifying the object, return the computed changes and assign it back to the original variable. Below are sample code snippets …
Continue reading “Does modifying objects passed in to functions modify original object?”
Been using a lot of Log.d(TAG, “message”); when working on Android projects. Problem with TAG is that it needs to be explicitly declared, e.g. protected String TAG = MyClass.class.getSimpleName(); instead of being inferred. Unlike PHP, Java has no magic constants such as __CLASS__ or __FUNCTION__ that can resolve automagically to the class/method being used at …
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Been playing with ExoPlayer in Android and trying to resize a view to fit the aspect ratio of the video being played, i.e. fill the view with the video. References: Change resize mode for ExoPlayer Change aspect ratio of SurfaceView for ExoPlayer video 5-part series on building video player using ExoPlayer import android.view.ViewGroup.LayoutParams; import com.google.android.exoplayer2.Player.EventListener; …
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When we design a user interface (UI) for our application, we want it to be user-friendly, for the user to have a good user experience (UX). How about application programming interfaces (API)? Shouldn’t an API be designed to be user-friendly as well? And in this case, who are the main users/consumers of APIs? Developers, of …
Continue reading “Designing Developer-Friendly JSON for API responses”
For more information on the ESC/POS command set which receipt printers use for printing, see What is ESC/POS and How Do I Use It by Michael Billington, also the author of the excellent escpos-php PHP library for receipt printers. Thanks to this StackOverflow post as well: printing QR codes through an ESC/POS thermal printer? 🙂 …
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For more information on the ESC/POS command set which receipt printers use for printing, see What is ESC/POS and How Do I Use It by Michael Billington, also the author of the excellent escpos-php PHP library for receipt printers. Steps to run: Save the code below as NetworkReceiptPrinter.java – change printer IP accordingly. Run javac …
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This executes a shell command in Scala and returns the actual server IP instead of 127.0.0.1 or the domain name of the host. #| is used to simulate piping of commands. Process and Seq are used for awk as $NF will lead to compilation errors otherwise. The actual shell command is: ip route get 8.8.8.8 …
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For future reference…after spending quite some time figuring it out 😛 package models; import com.avaje.ebean.Model; import com.avaje.ebean.Query; import play.Logger; import play.data.validation.Constraints; import java.util.Date; import java.util.List; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.Id; import javax.persistence.Table; @Entity @Table(name = “my_table”) public class MyModel extends Model { @Id public Long id; @Column(name = “name”) public String name; @Constraints.Required @Column(name …
Continue reading “Using COALESCE and logging SQL string in Play Framework 2.x”
