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Add a keystore using: keytool -genkey -v -keystore example.keystore -alias example -keyalg RSA -keysize 2048 -validity 10000 Note: This should be at root of project. Though not a hard requirement, it eases the file referencing Add a build.json with release/dev configuration for key...

To view a pdf you can download Adobe reader for free . You can create pdfs programmatically with the help of, e.g by using iTextSharp, jsPDF or PDFSharp (there are other libraries available)

Early Bound (with a reference to Microsoft Scripting Runtime) Sub EnumerateFilesAndFolders( _ FolderPath As String, _ Optional MaxDepth As Long = -1, _ Optional CurrentDepth As Long = 0, _ Optional Indentation As Long = 2) Dim FSO As Scripting.FileSystemObject Set ...

Split Function returns a zero-based, one dimensional array containing a specified number of substrings. Syntax Split(expression [, delimiter [, limit [, compare]]]) PartDescriptionexpressionRequired. String expression containing substrings and delimiters. If expression is a zero-length string(&q...

When using non-lazy translation, strings are translated immediately. >>> from django.utils.translation import activate, ugettext as _ >>> month = _("June") >>> month 'June' >>> activate('fr') >>> _("June") 'juin' >>> a...

Prefer dict.get method if you are not sure if the key is present. It allows you to return a default value if key is not found. The traditional method dict[key] would raise a KeyError exception. Rather than doing def add_student(): try: students['count'] += 1 except KeyError: ...

First, add Mongoid to your Gemfile: gem "mongoid", "~> 4.0.0" and then run bundle install. Or just run: $ gem install mongoid After installation, run the generator to create the config file: $ rails g mongoid:config which will create the file (myapp)/config/mongoid...

Create a model (lets call it User) by running: $ rails g model User which will generate the file app/models/user.rb: class User include Mongoid::Document end This is all you need to have a model (albeit nothing but an id field). Unlike ActiveRecord, there is no migration files. All the...

Mongoid allows the classic ActiveRecord associations: One-to-one: has_one / belongs_to One-to-many: has_many / belongs_to Many-to-many: has_and_belongs_to_many To add an association (lets say the User has_many posts), you can add this to your User model file: has_many :posts and this to ...

Mongoid allows Embedded Associations: One-to-one: embeds_one / embedded_in One-to-many: embeds_many / embedded_in To add an association (lets say the User embeds_many addresses), add this to your User file: embeds_many :addresses and this to your Address model file: embedded_in :user ...

Mongoid tries to have similar syntax to ActiveRecord when it can. It supports these calls (and many more) User.first #Gets first user from the database User.count #Gets the count of all users from the database User.find(params[:id]) #Returns the user with the id found in params[:id] User.w...

One of the simplest ways to control program flow is by using if selection statements. Whether a block of code is to be executed or not to be executed can be decided by this statement. The syntax for if selection statement in C could be as follows: if(cond) { statement(s); /*to be executed, o...

While if performs an action only when its condition evaluate to true, if / else allows you to specify the different actions when the condition true and when the condition is false. Example: if (a > 1) puts("a is larger than 1"); else puts("a is not larger than 1"...

MySQL does not provide a built-in way to create pivot queries. However, these can be created using prepared statements. Assume the table tbl_values: IdNameGroupValue1PeteA102PeteB203JohnA10 Request: Create a query that shows the sum of Value for each Name; the Group must be column header and Name...

globalize gem is a great solution to add translations to your ActiveRecord models. You can install it adding this to your Gemfile: gem 'globalize', '~> 5.0.0' If you're using Rails 5 you will also need to add activemodel-serializers-xml gem 'activemodel-serializers-xml' Model translations...

Due to type erasure the following will not work: public <T> void genericMethod() { T t = new T(); // Can not instantiate the type T. } The type T is erased. Since, at runtime, the JVM does not know what T originally was, it does not know which constructor to call. Workarounds ...

When an HTTP server receives a well-formed HTTP request, it must process the information that request contains and return a response to the client. A simple HTTP 1.1 response, may look like any of the following, usually followed by a number of header fields, and possibly a response body: HTTP/1.1 2...

A common problem is having a collection of items that all need to meet a certain criteria. In the example below we have collected two items for a diet plan and we want to check that the diet doesn't contain any unhealthy food. // First we create a collection $diet = collect([ ['name' => ...

Often you need to change the way a set of data is structured and manipulate certain values. In the example below we got a collection of books with an attached discount amount. But we much rather have a list of books with a price that's already discounted. $books = [ ['title' => 'The Pragma...

Collections also provide you with an easy way to do simple statistical calculations. $books = [ ['title' => 'The Pragmatic Programmer', 'price' => 20], ['title' => 'Continuous Delivery', 'price' => 30], ['title' => 'The Clean Coder', 'price' => 10], ] $min = col...