Tutorial by Examples: er

In this example, base class Singleton provides getMessage() method that returns "Hello world!" message. It's subclasses UppercaseSingleton and LowercaseSingleton override getMessage() method to provide appropriate representation of the message. //Yeah, we'll need reflection to pull this ...

Choosing which C++ Container to use can be tricky, so here's a simple flowchart to help decide which Container is right for the job. This flowchart was based on Mikael Persson's post. This little graphic in the flowchart is from Megan Hopkins

Static members have class scope as opposed to object scope C++ Example // define in header class Singleton { public: static Singleton *getInstance(); private: Singleton() {} static Singleton *instance; }; // initialize in .cpp Singleton* Singleton::instance = 0...

Defined within Another Class C++ Nested Class[ref] (needs a reference to enclosing class) class Outer { class Inner { public: Inner(Outer* o) :outer(o) {} private: Outer* outer; }; }; Java [non-static] Nested Class (aka Inner Class or Member Class...

Many argue that Java is ONLY pass-by-value, but it's more nuanced than that. Compare the following C++ and Java examples to see the many flavors of pass-by-value (aka copy) and pass-by-reference (aka alias). C++ Example (complete code) // passes a COPY of the object static void passByCopy(Pa...

C++ & Java are both object-oriented languages, thus the following diagram applies to both.

Add a new file to Xcode (File > New > File), then select “Source” and click “Header File“. Name your file “YourProjectName-Bridging-Header.h”. Example: In my app Station, the file is named “Station-Bridging-Header”. Create the file. Navigate to your project build settings ...

To find the word foo in the file bar : grep foo ~/Desktop/bar To find all lines that do not contain foo in the file bar : grep –v foo ~/Desktop/bar To use find all words containing foo in the end (WIldcard Expansion): grep "*foo" ~/Desktop/bar

In iTunes Connect, click iTunes Connect in the top left corner of the window to get back to the main menu. Select Users and Roles, then click the Sandbox Testers tab. Click + next to the “Tester” title. Fill out the information and click Save when you’re done. You can make up a first and last nam...

For an executable file or command exec, running this will list all system calls: $ ptrace exec To display specific system calls use -e option: $ strace -e open exec To save the output to a file use the -o option: $ strace -o output exec To find the system calls an active program uses, us...

HTML: <ul> <li>Mango</li> <li>Book</li> </ul> Script: $( "li" ).each(function( index ) { console.log( index + ": " + $( this ).text() ); }); A message is thus logged for each item in the list: 0: Mango 1: Book

Many symbols and special characters are required while developing a web page in html, but as we know that sometimes the use of characters directly may interfere with the actual html code which have certain characters reserved and also certain characters being not available on keyboard. Thus, to avoi...

This is continuation of previous example. Cascading DropDown for country's city name. This method will be called by Jquery when user is done with country selection in parent dropdown. I have followed MVC concept and provided the basic approach for cascading dropdown. Ajax will call GetCityName met...

For most of the scenarios involving entities from service layer,we can make do with the default service calls,with some help from the finders as well.For simple scenarios involving multiple entities,we move towards using Dynamic query API.This is a wrapper API for the Criteria API used in Hibernate....

Code Group group = new Group(); group.setId(1); group.setName("Ke"); User user1 = new User(); user1.setId(2); user1.setName("Liu"); User user2 = new User(); user2.setId(3); user2.setName("Yue"); ...

After installing perforce and setup your workspace through p4v, you could set up your workspace in Windows cmd. The command you need is: p4 set Set your server p4 set P4PORT= xx.xxx.xx.xxx:xxxxx Set your user name p4 set P4USER=username Set your password In terms of setting your passwo...

final AsynchronousJiraRestClientFactory factory = new AsynchronousJiraRestClientFactory(); restClient = factory.createWithBasicHttpAuthentication(URI.create(JIRA_SERVER), JIRA_LOGIN, JIRA_PASSWORD); getFilteredIssues("project = TestProject"); public Iterable<Issue> getFilteredIs...

Room require four parts: Database class, DAO classes, Entity classes and Migration classes (now you may use only DDL methods): Entity classes // Set custom table name, add indexes @Entity(tableName = "videos", indices = {@Index("title")} ) public final class VideoIt...

Handy method to initialise SolrJ client based on configuration properties; private void initSolrClient() { if (conf.kerberos().isEnabled()) { System.setProperty("java.security.auth.login.config", conf.kerberos().confPath()); HttpClientUtil.addConfigurer(new Krb5Http...

PSR-4 is an accepted recommendation that outlines the standard for autoloading classes via filenames. This recommendation is recommended as the alternative to the earlier (and now deprecated) PSR-0. The fully qualified class name should match the following requirement: \<NamespaceName>(\&lt...