Tutorial by Examples: p

Using some setters, without setting all needed properties in the constructor(s) public final class Person { // example of a bad immutability private final String name; private final String surname; public Person(String name) { this.name = name; } public String ge...

JasperSoft Studio If datasource or database connection is needed to fill report, create your Data Adapter in Repository Explorer by right clicking "Data Adapters" selecting "Create Data Adapter" Enter preview mode by selecting the Preview tab (no errors in deign need t...

Common Requirements All reports, regardless of how the data is presented, take a path to the report template and a parameter map. The variables are used in all examples that follow: // Parameters passed into the report. Map<String, Object> parameters = new HashMap<>(); // Arbitrary...

When you have multiple subscriptions under your Azure account; it's important that you are selecting the one you wish to operate on (and use this as default); to avoid accidents happening to resources on the wrong subscription. Classic mode Set-AzureSubscription Select-AzureSubscription Resou...

Create a new project with the Leiningen figwheel template: lein new figwheel hello-world Run Figwheel: cd hello-world lein figwheel After a moment it will start a development webserver and open the page in your browser. It also opens a Clojurescript REPL connected to the browser. Try enter...

:s/foo/bar/c Marks the first instance of foo on the line and asks for confirmation for substitution with bar :%s/foo/bar/gc Marks consecutively every match of foo in the file and asks for confirmation for substitution with bar

Some ADO.NET providers (most notably: OleDB) do not support named parameters; parameters are instead specified only by position, with the ? place-holder. Dapper would not know what member to use for these, so dapper allows an alternative syntax, ?foo?; this would be the same as @foo or :foo in other...

It's possible to pass Java objects to Nashorn engine to be processed in Java code. At the same time, there are some JavaScript (and Nashorn) specific constructions, and it's not always clear how they work with java objects. Below there is a table which describes behaviour of native Java objects ins...

In C, a pointer can refer to another pointer. #include <stdio.h> #include <stdlib.h> int main(void) { int A = 42; int* pA = &A; int** ppA = &pA; int*** pppA = &ppA; printf("%d", ***pppA); /* prints 42 */ return EXIT_SUCCESS; } But, ref...

Debug Print shows the instance representation that is most suitable for debugging. print("Hello") debugPrint("Hello") let dict = ["foo": 1, "bar": 2] print(dict) debugPrint(dict) Yields >>> Hello >>> "Hello" >&gt...

Violin plots are kernel density estimates mirrored in the vertical plane. They can be used to visualize several distributions side-by-side, with the mirroring helping to highlight any differences. ggplot(diamonds, aes(cut, price)) + geom_violin() Violin plots are named for their resemblance...

If you are unsure which rules to list in your .gitignore file, or you just want to add generally accepted exceptions to your project, you can choose or generate a .gitignore file: https://www.toptal.com/developers/gitignore https://github.com/github/gitignore Many hosting services such as Git...

async.parallel(tasks, afterTasksCallback) will execute a set of tasks in parallel and wait the end of all tasks (reported by the call of callback function). When tasks are finished, async call the main callback with all errors and all results of tasks. function shortTimeFunction(callback) { set...

async.series(tasks, afterTasksCallback) will execute a set of tasks. Each task are executed after another. If a task fails, async stops immediately the execution and jump into the main callback. When tasks are finished successfully, async call the "master" callback with all errors and all...

async.waterfall(tasks, afterTasksCallback) will execute a set of tasks. Each task are executed after another, and the result of a task is passed to the next task. As async.series(), if a task fails, async stop the execution and call immediately the main callback. When tasks are finished successfull...

Dropping the database is a simple one-liner statement. Drop database will delete the database, hence always ensure to have a backup of the database if required. Below is the command to drop Employees Database DROP DATABASE [dbo].[Employees]

Use the yum command to manage packages in Enterprise Linux-based operating systems: yum install php This installs a minimal install of PHP including some common features. If you need additional modules, you will need to install them separately. Once again, you can use yum to search for these pac...

Note: There will be some Objective-c in this example.. We will make a wrapper to C++ in this example, So don't worry to much about it. First start Xcode and create a project. And select a Cocoa application Delete all sources except the Info.plist file.(Your app won't work without it) Creat...

You should always use <?php ?> tags or short-echo tags <?= ?>. Other variations (in particular, short tags <? ?>) should not be used as they are commonly disabled by system administrators. When a file is not expected to produce output (the entire file is PHP code) the closing ?&gt...

Improper Inheritance Lets say there are 2 classes class Foo and Bar. Foo has two features Do1 and Do2. Bar needs to use Do1 from Foo, but it doesn't need Do2 or needs feature that is equivalent to Do2 but does something completely different. Bad way: make Do2() on Foo virtual then override it in B...