Tutorial by Examples: ce

The following technique allows you to add your content to an HTML element and center it both horizontally and vertically without worrying about its height or width. The outer container should have display: table; The inner container should have display: table-cell; should have vertical-al...

Similar to partial classes the new version of Visual Basic is now able to handle partial modules and partial interfaces. The syntax and behaviour is exactly the same as it would be for partial classes. A partial module example: Partial Module Module1 Sub Main() Console.Write("Ping -&g...

class Example { void method(boolean error) { if (error) { Log.error("Error occurred!"); System.out.println("Error!"); } else { // Use braces since the other block uses braces. System.out.println("No error"); ...

Line Length // Lines should never exceed 100 characters. // Instead, just wrap on to the next line. let bad_example = "So this sort of code should never really happen, because it's really hard to fit on the screen!"; Indentation // You should always use 4 spaces for indentation. ...

You can test that a function throws an exception with the built-in unittest through two different methods. Using a context manager def division_function(dividend, divisor): return dividend / divisor class MyTestCase(unittest.TestCase): def test_using_context_manager(self): ...

When executing a Bash script, parameters passed into the script are named in accordance to their position: $1 is the name of the first parameter, $2 is the name of the second parameter, and so on. A missing parameter simply evaluates to an empty string. Checking for the existence of a parameter can...

Interfaces can seem abstract until you seem them in practice. The IComparable and IComparable<T> are great examples of why interfaces can be helpful to us. Let's say that in a program for a online store, we have a variety of items you can buy. Each item has a name, an ID number, and a price. ...

VB.NET offers default Form instances. The developer does not need to create the instance as it is created behind the scenes. However, it is not preferable to use the default instance all but the simplest programs. Public Class Form1 Public Sub Foo() MessageBox.Show("Bar") ...

Here we consider sums of the form a + b + a + b + ... a vs. a + b + a + b + ... b To visualize these sums, imagine a section of fence alternating between posts and rails. Three scenarios are possible. Imagine a section of fence with posts at each end, connected by rails. n rails require...

Declare JNDI resource in tomcat's server.xml, using the Tomcat JDBC connection pool: <GlobalNamingResources> <Resource name="jdbc/DatabaseName" factory="org.apache.tomcat.jdbc.pool.DataSourceFactory" auth="Container" ...

Here we have a class and we want the identity field (userUid) to have its value generated via a SEQUENCE in the database. This SEQUENCE is assumed to be called USER_UID_SEQ, and can be created by a DBA, or can be created by the JPA provider. @Entity @Table(name="USER") public class User...

If you want to remove calls to certain methods, assuming they return void and have no side affects (as in, calling them doesn't change any system values, reference arguments, statics, etc.) then you can have ProGuard remove them from the output after the build is complete. For example, I find this ...

SELECT statement can be executed without FROM clause: declare @var int = 17; SELECT @var as c1, @var + 2 as c2, 'third' as c3 In this case, one row with values/results of expressions are returned.

Enable Offline Work: Click File -> Settings. Search for "gradle" and click in Offline work box. Go to Compiler (in same settings dialog just below Gradle) and add --offline to Command-line Options text box. Improve Gradle Performance Add following two line of code in your gradle...

We want to process data in parallel. Let's populate source with some data: source = Queue.new data = (1..100) data.each { |e| source << e } Then create some workers to process data: (1..16).to_a.map do Thread.new do until source.empty? item = source.pop sleep 0.5 ...

We want to process data in parallel and push it down the line to be processed by other workers. Since Workers both consume and produce data we have to create two queues: first_input_source = Queue.new first_output_sink = Queue.new 100.times { |i| first_input_source << i } First wave of...

The following class is used to demonstrate, how instances of classes can be created: JavaFX 8 The annotation in Person(@NamedArg("name") String name) has to be removed, since the @NamedArg annotation is unavailable. package fxml.sample; import javafx.beans.NamedArg; import javafx....

In most cases, it is illegal to access an object of one type as though it were a different type (disregarding cv-qualifiers). Example: float x = 42; int y = reinterpret_cast<int&>(x); The result is undefined behavior. There are some exceptions to this strict aliasing rule: An obj...

The ProcessBuilder class makes it easy to send a command through the command line. All it requires is a List of Strings that make up the commands to be entered. You simply call the start() method on your ProcessBuilder instance to execute the command. If you have a program called Add.exe which take...

For example: ActiveRecord::Base.transaction do david.withdrawal(100) mary.deposit(100) end This example will only take money from David and give it to Mary if neither withdrawal nor deposit raise an exception. Exceptions will force a ROLLBACK that returns the database to the state before ...