I’ve had similar problem. AFAIK there is no build-in functionality in OpenCSV that will allow to write bean to CSV with custom column names and ordering. There are two main MappingStrategyies that are available in OpenCSV out of the box: HeaderColumnNameMappingStrategy: that allows to map CVS file columns to bean fields based on custom name; …
Void is a special class usually used only for reflection – its primary use is to represent the return type of a void method. From the javadoc for Void: The Void class is an uninstantiable placeholder class to hold a reference to the Class object representing the Java keyword void. Because the Void class can …
You still need to create the array, even if you do not assign it to a variable. Try this: public int[] getData() { return new int[] {a,b,c,d}; } Your code sample did not work because the compiler, for one thing, still needs to know what type you are attempting to create via static initialization {}.
Not sure if I understand your question correctly, but provided that you can call the Python executable from the console and just want to capture its output in Java, you can use the exec() method in the Java Runtime class. Process p = Runtime.getRuntime().exec(“python yourapp.py”); You can read up on how to actually read the …
In your build.gradle file, add the following to the end of the Android node: android { …. …. sourceSets { main.java.srcDirs += ‘src/main/<YOUR DIRECTORY>’ } }
Since Exception is a checked exception, you either: Have to catch the exception in a try…catch statement, or Declare the exception to be thrown in the method itself. What you have up there works fine, but my personal preference is to declare the exception to be thrown. This way, if an exception I’m not expecting …
try(ImageInputStream in = ImageIO.createImageInputStream(resourceFile)){ final Iterator<ImageReader> readers = ImageIO.getImageReaders(in); if (readers.hasNext()) { ImageReader reader = readers.next(); try { reader.setInput(in); return new Dimension(reader.getWidth(0), reader.getHeight(0)); } finally { reader.dispose(); } } } Thanks to sfussenegger for the suggestion
In Java, == always just compares two references (for non-primitives, that is) – i.e. it tests whether the two operands refer to the same object. However, the equals method can be overridden – so two distinct objects can still be equal. For example: String x = “hello”; String y = new String(new char[] { ‘h’, …
A constructor in Java doesn’t actually “build” the object, it is used to initialize fields. Imagine that your abstract class has fields x and y, and that you always want them to be initialized in a certain way, no matter what actual concrete subclass is eventually created. So you create a constructor and initialize these …
Add permission <uses-permission android:name=”android.permission.REQUEST_IGNORE_BATTERY_OPTIMIZATIONS”/> request whitelist your app if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) { Intent intent = new Intent(); String packageName = getPackageName(); PowerManager pm = (PowerManager) getSystemService(POWER_SERVICE); if (!pm.isIgnoringBatteryOptimizations(packageName)) { intent.setAction(Settings.ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS); intent.setData(Uri.parse(“package:” + packageName)); startActivity(intent); } }