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In some circumstances (for example obtaining a Google API key) you need to find your keystore fingerprint. Gradle has a convenient task that display all the signing information, including keystore fingerprints: ./gradlew signingReport This is a sample output: :app:signingReport Variant: releas...

X-Macros can be used for code generation, by writing repetitive code: iterate over a list to do some tasks, or to declare a set of constants, objects or functions. Here we use X-macros to declare an enum containing 4 commands and a map of their names as strings Then we can print the string values ...

Enums contains only constants and can be compared directly with ==. So, only reference check is needed, no need to use .equals method. Moreover, if .equals used incorrectly, may raise the NullPointerException while that's not the case with == check. enum Day { GOOD, AVERAGE, WORST; } publi...

The Standard (10.4) states: Member functions can be called from a constructor (or destructor) of an abstract class; the effect of making a virtual call (10.3) to a pure virtual function directly or indirectly for the object being created (or destroyed) from such a constructor (or destructor) is u...

Most, but not all, C++ implementations support the #pragma once directive which ensures the file is only included once within a single compilation. It is not part of any ISO C++ standard. For example: // Foo.h #pragma once class Foo { }; While #pragma once avoids some problems associated w...

Installation Volley JCenter Gradle Import //in your project's app level build.gradle compile 'com.android.volley:volley:1.0.0' Create a subclass of Application public class AppController extends Application { public static final String TAG = AppController.class .getSimpleN...

.set-colors(@type) when (@type = error) { @base-color: #d9534f; background: @base-color; color: contrast(@base-color, lighten(@base-color, 25%), darken(@base-color, 25%)); border: 1px solid contrast(@base-color, lighten(@base-color, 25%), darken(@base-color, 25%)); } .set-colors(@type)...

Shows the version of bash that is running, this allows you to decide whether you can use any advanced features: ~> $ echo $BASH_VERSION 4.1.2(1)-release

The number of seconds a script has been running. This can get quite large if shown in the shell: ~> $ echo $SECONDS 98834

Consider this example function to check if a host is up: is_alive() { ping -c1 "$1" &> /dev/null } This function sends a single ping to the host specified by the first function parameter. The output and error output of ping are both redirected to /dev/null, so the functi...

Detailed instructions on getting google-bigquery set up or installed.

Inside your layout, add a Login button with the following code: <com.twitter.sdk.android.core.identity.TwitterLoginButton android:id="@+id/twitter_login_button" android:layout_width="wrap_content" android:layout_height="wrap_content" and...

The class use Phalcon\Validation\Validator; use Phalcon\Validation\ValidatorInterface; use Phalcon\Validation\Message; class RecaptchaValidator extends Validator implements ValidatorInterface { public function validate(\Phalcon\Validation $validation, $attribute) { $value =...

Things you need A paid Apple Developer Program Membership A valid App ID and identifier for you app (like com.example.MyApp) which is not used before anywhere Access to developer.apple.com and Member Center An iOS Device to test (as Push Notifications don't work on Simulator) Enabling t...

You can find description of the driver here. The quick example is: import psycopg2 db_host = 'postgres.server.com' db_port = '5432' db_un = 'user' db_pw = 'password' db_name = 'testdb' conn = psycopg2.connect("dbname={} host={} user={} password={}".format( ...

In order to use Gson you have to include it in your project. You can do this by adding the following dependency of the Gson version available in Maven Central: Maven Add to pom.xml <dependencies> <dependency> <groupId>com.google.code.gson</groupId> <a...

There're several conventions of calling functions, specifying who (caller or callee) pops arguments from the stack, how arguments are passed and in what order. C++ uses Cdecl calling convention by default, but C# expects StdCall, which is usually used by Windows API. You need to change one or the ot...

In Solution Explorer go to your project, right click on References then Add reference… Search for Compression and select System.IO.Compression.FileSystem then press OK. Add Imports System.IO.Compression to the top of your code file (before any class or module, with the other Imports statements)....

Hive-Hbase integration is supported since below versions. Hive: 0.11.0 HBase: 0.94.2 Hadoop: 0.20.2 CREATE TABLE hbase_hive (id string, col1 string, col2 string, col3 int) STORED BY 'org.apache.hadoop.hive.hbase.HBaseStorageHandler' WITH SERDEPROPERTIES ("hbase.columns.mapping&q...

On Debian or Ubuntu, you can install SCons using $ sudo apt-get install scons On YUM-based systems, use $ sudo yum install scons You can install using an RPM by downloading it, then running $ sudo rpm -Uvh http://prdownloads.sourceforge.net/scons/scons-2.5.0-1.noarch.rpm