Tutorial by Examples: ce

Multiple Producers and Consumers Sharing the same buffer

This example shows multiple producers and consumers sharing the same buffer. Protected entries in Ada implement a queue to handle waiting tasks. The default queuing policy is First In First Out. ------------------------------------------------------------------ -- Multiple producers and consumers ...

ada • Implementing the producer-consumer pattern

Inheritance from Parent Class to Child Class

class ParentClass { [string] $Message = "Its under the Parent Class" [string] GetMessage() { return ("Message: {0}" -f $this.Message) } } # Bar extends Foo and inherits its members class ChildClass : ParentClass { } $Inherit = [ChildClass...

PowerShell • PowerShell Classes

Use generics to enhance type-safety

Let's take this example without using generics protocol JSONDecodable { static func from(_ json: [String: Any]) -> Any? } The protocol declaration seems fine unless you actually use it. let myTestObject = TestObject.from(myJson) as? TestObject Why do you have to cast the result to T...

Swift Language • Generics

Accessing variables

In Twig templates variables can be accessed using double curly braces notation {{ variableName }}. Basic example of greeting user <!DOCTYPE html> <html> <body> <span>Hello {{ name }}</span> </body> </html> Accessing array elements Twig as ...

twig • Basic template syntax

Basic spring security with annotation, SQL datasource

@Configuration public class AppSecurityConfig extends WebSecurityConfigurerAdapter { @Autowired DataSource dataSource; @Autowired public void configureGlobal(AuthenticationManagerBuilder auth) throws Exception { auth.jdbcAuthentication().dataSource(dataSource) .pa...

spring-security • Spring Security config with java (not XML)

RunTime Type Services

RunTime Type Services (short: RTTS) are used either for: creating types (RunTime Type Creation; short: RTTC) analysing types (RunTime Type Identification; short: RTTI) Classes CL_ABAP_TYPEDESCR | |--CL_ABAP_DATADESCR | | | |--CL_ABAP_ELEMDESCR | |--CL_ABAP_REFDESCR ...

ABAP • Dynamic Programming

Generating certificates

Generate a RSA private key: openssl genrsa -des3 -out server.key 4096 Openssl should ask for a pass phrase at this step. Notice that we’ll use only certificate for communication and authentication, without pass phrase. Just use 123456 for example. Generate the Certificate Signing Request: openssl ...

Docker • Docker private/secure registry with API v2

Run the registry with self-signed certificate

To run the private registry (securely) you have to generate a self-signed certificate, you can refer to previous example to generate it. For my example I put server.key and server.crt into /root/certs Before run docker command you should be placed (use cd) into the directory that contains certs fo...

Docker • Docker private/secure registry with API v2

Write the ansible playbook to create the instance

Let use 'os_server' command from module 'Cloud' [http://docs.ansible.com/ansible/os_server_module.html]. Variables are defined in ./group_vars/all. $vi launch_compute.yml - name: launch a compute instance hosts: localhost gather_facts: False tasks: - name: Create and launch the VM ...

ansible • Using Ansible with OpenStack

Gather informations about our new instance

Use the 'os_server_facts' command from module 'Cloud' [http://docs.ansible.com/ansible/os_server_module.html]. Variables are defined in ./group_vars/all and the instance name is in server: "MyOwnPersonalInstance". $vi get_compute_info.yml - name: Get and print instance IP hosts: loca...

ansible • Using Ansible with OpenStack

Get your new instance public IP

Instead of printing all the informations, we print only IP address of the first instance whose name is "MyOwnPersonalInstance". It's usually all we need. $vi get_compute_ip.yml - name: Get and print instance IP hosts: localhost gather_facts: False tasks: - name: Get VM infos...

ansible • Using Ansible with OpenStack

Delete our instance

To delete our instance, reuse the os_server command with all authentication information and simply replace ' state: present' by ' state: absent'. $vi stop_compute.yml - name: launch a compute instance hosts: localhost gather_facts: False tasks: - name: Create and launch the VM os_...

ansible • Using Ansible with OpenStack

Installation from Source (with Postgres 9.1 or higher)

This guide is explicitly for PostgreSQL 9.1 or higher on linux machines. It uses the postgres extensions-feature that will greatly improve the import of extensions to an existing postgres-installation. If you have to work with an older version of postgres, please refer to the official documentations...

postgis • Getting started with postgis

Using Interfaces for Polymorphism

The primary reason to use interfaces to achieve polymorphism and provide developers to implement on their own way in future by implementing interface's methods. Suppose we have an interface and three classes: interface Connector{ doConnect(): boolean; } This is connector interface. Now we...

TypeScript • Interfaces

General Information about Databases, Tables, Stored procedures and how to search them.

Query to search last executed sp's in db SELECT execquery.last_execution_time AS [Date Time], execsql.text AS [Script] FROM sys.dm_exec_query_stats AS execquery CROSS APPLY sys.dm_exec_sql_text(execquery.sql_handle) AS execsql ORDER BY execquery.last_execution_time DESC Query to search thro...

Microsoft SQL Server • Retrieve Information about your Instance

asterisk installation on CentOS 6.X

Asterisk is an open source framework for building communications applications. You can use it for any of the following: IP PBX systems VoIP gateways ISDN/ 3G IVVR Here is a brief instruction for step by step installation of asterisk 1.8(or you can do for latest versions) on Redhat/centos (fo...

Asterisk • Getting started with Asterisk

Location Services in the Background

To use standard location services while the application is in the background you need first turn on Background Modes in the Capabilities tab of the Target settings, and select Location updates. Or, add it directly to the Info.plist. <key>NSLocationAlwaysUsageDescription</key> <st...

iOS • Core Location

Merging cells

//By range address worksheet.Cells["A1:B5"].Merge = true; //By indexes worksheet.Cells[1,1,5,2].Merge = true;

epplus • Merge Cells

Create a DSC Resource Skeleton Class

[DscResource()] class File { } This example demonstrates how to build the outer section of a PowerShell class, that declares a DSC Resource. You still need to fill in the contents of the class definition.

PowerShell • Creating DSC Class-Based Resources

DSC Resource Skeleton with Key Property

[DscResource()] class Ticket { [DscProperty(Key)] [string] $TicketId } A DSC Resource must declare at least one key property. The key property is what uniquely identifies the resource from other resources. For example, let's say that you're building a DSC Resource that represents a ticket...

PowerShell • Creating DSC Class-Based Resources