Tutorial by Examples: d

The ls command has several options that can be used together to show more information. Details/Rights The l option shows the file permissions, size, and last modified date. So if the root directory contained a dir called test and a file someFile the command: user@linux-computer:~$ ls -l Would ...

Most modern distributions will come with BASH (Bourne Again SHell) pre-installed and configured as a default shell. The command (actually an executable binary, an ELF) that is responsible for changing shells in Linux is chsh (change shell). We can first check which shells are already installed and...

Observables are broadly categorised as Hot or Cold, depending on their emission behaviour. A Cold Observable is one which starts emitting upon request(subscription), whereas a Hot Observable is one that emits regardless of subscriptions. Cold Observable /* Demonstration of a Cold Observable */ Ob...

A deadlock occurs when two competing actions wait for the other to finish, and thus neither ever does. In java there is one lock associated with each object. To avoid concurrent modification done by multiple threads on single object we can use synchronized keyword, but everything comes at a cost....

A type of dialog that contains an alert message, where initial focus goes to an element within the dialog. <div role="alertdialog"> <h1>Warning</h1> <div role="alert">Your session will expire in 60 seconds.</div> </div>

A cell containing header information for a column. <table role="grid"> <thead> <tr> <th role="columnheader">Day 1</th> <th role="columnheader">Day 2</th> <th role="columnheader">Day ...

A definition of a term or concept. <span role="term" aria-labelledby="def1">Love</span> <span id="def1" role="definition">an intense feeling of deep affection.</span>

A dialog is an application window that is designed to interrupt the current processing of an application in order to prompt the user to enter information or require a response. <div role="dialog"> <p>Are you sure?</p> <button role="button">Yes</b...

A list of references to members of a group, such as a static table of contents. <ul role="directory"> <li><a href="/chapter-1">Chapter 1</a></li> <li><a href="/chapter-2">Chapter 2</a></li> <li><a ...

A region containing related information that is declared as document content, as opposed to a web application. <div role="document"> <h1>The Life of Albert Einstein</h1> <p>Lorem ipsum...</p> </div>

A grid is an interactive control which contains cells of tabular data arranged in rows and columns, like a table. <table role="grid"> <thead> <!-- etc --> </thead> <tbody> <!-- etc --> </tbody> </table>

A cell in a grid or treegrid. <table role="grid"> <thead> <!-- etc --> </thead> <tbody> <tr> <td role="gridcell">17</td> <td role="gridcell">64</td> <td role="gr...

A heading for a section of the page. <h1 role="heading">Introduction</h1> <p>Lorem ipsum...</p>

A checkable menuitem in a group of menuitemradio roles, only one of which can be checked at a time. <ul role="menu"> <li role="menuitemradio" aria-checked="true">Left</li> <li role="menuitemradio" aria-checked="false">C...

A checkable input in a group of radio roles, only one of which can be checked at a time. <div role="radiogroup"> <input role="radio" type="radio" aria-checked="true"> One<br> <input role="radio" type="radio" aria...

A group of radio buttons. <div role="radiogroup"> <input role="radio" type="radio" aria-checked="true"> One<br> <input role="radio" type="radio" aria-checked="false"> Two<br> <input role=...

A cell containing header information for a row in a grid. <table role="grid"> <thead> <!-- etc --> </thead> <tbody> <tr> <th role="rowheader">Day 1</th> <td>65</td> </tr> ...

A user input where the user selects a value from within a given range. <div role="slider" aria-valuemax="100" aria-valuemin="0" aria-valuenow="25"> <div class="sliderhandle"></div> </div>

A grid whose rows can be expanded and collapsed in the same manner as for a tree.

import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; public class ReadingUTF8TextFile { public static void main(String[] args) throws IOException { ...