Tutorial by Examples: o

Numbering the nodes of a tree with a counter

We have a tree data type like this: data Tree a = Tree a [Tree a] deriving Show And we wish to write a function that assigns a number to each node of the tree, from an incrementing counter: tag :: Tree a -> Tree (a, Int) The long way First we'll do it the long way around, since it illust...

Haskell Language • State Monad

Old Doctypes

HTML 3.2 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> HTML 3.2 is well supported by most browsers in use. However, HTML 3.2 has limited support for style sheets and no support for HTML 4 features such as frames and internationalization. HTML 2.0 <!DOCTYPE HTML P...

HTML • Doctypes

Converting All Tables in one Database

To easily convert all tables in one database, use the following: SET @DB_NAME = DATABASE(); SELECT CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements FROM information_schema.tables WHERE table_schema = @DB_NAME AND `ENGINE` = 'MyISAM' AND `TABLE_TYPE` = '...

MySQL • Converting from MyISAM to InnoDB

Configuration

Manage Roles Global Roles- Create roles with selected set of Jenkins features e.g. Usually for a development project, 2 roles can be created. Developer- Global role can be set to only Overall : Read ProjectOwner- Global role can be set to Overall : Read This restricts developer and project ...

jenkins • Role Strategy Plugin

Bi-Directional Many to Many using user managed join table object

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany(mappedBy = "bar") private List<FooBar> bars; } @Entity @Table(name="BAR") public class Bar { private UUID barId; @OneToMany(mappedBy = "f...

hibernate • Hibernate Entity Relationships using Annotations

Bi-Directional Many to Many using Hibernate managed join table

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany @JoinTable(name="FOO_BAR", joinColumns = @JoinColumn(name="fooId"), inverseJoinColumns = @JoinColumn(name="barId")) private List<Bar&g...

hibernate • Hibernate Entity Relationships using Annotations

Bi-directional One to Many Relationship using foreign key mapping

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany(mappedBy = "bar") private List<Bar> bars; } @Entity @Table(name="BAR") public class Bar { private UUID barId; @ManyToOne @JoinColumn(nam...

hibernate • Hibernate Entity Relationships using Annotations

Bi-Directional One to One Relationship managed by Foo.class

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToOne(cascade = CascadeType.ALL) @JoinColumn(name = "barId") private Bar bar; } @Entity @Table(name="BAR") public class Bar { private UUID barId; ...

hibernate • Hibernate Entity Relationships using Annotations

Uni-Directional One to Many Relationship using user managed join table

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany @JoinTable(name="FOO_BAR", joinColumns = @JoinColumn(name="fooId"), inverseJoinColumns = @JoinColumn(name="barId", unique=true)) private ...

hibernate • Hibernate Entity Relationships using Annotations

Uni-directional One to One Relationship

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToOne private Bar bar; } @Entity @Table(name="BAR") public class Bar { private UUID barId; //No corresponding mapping to Foo.class } Specifies a one-way relationship b...

hibernate • Hibernate Entity Relationships using Annotations

http and https redirects and HSTS configuration

Generic redirect to https: # Enable Rewrite engine RewriteEngine on # Check if URL does not contain https RewriteCond %{HTTPS} off [NC] # If condition is true, redirect to https RewriteRule (.*) https://%{SERVER_NAME}/$1 [R=301,L] Generic redirect to http: # Enable Rewrite engine Rewr...

Hypertext Access file • Rewriting and Redirecting

Using mod_rewrite in the static configuration file

Add the following directive before using any other mod_rewrite directive (RewriteRule, RewriteCond, RewriteBase or RewriteMap). RewriteEngine on By default the engine is turned off. mod_rewrite directives found while the engine is turned off are ignored. Enable it from within the virtual host co...

mod-rewrite • Getting started with mod-rewrite

Using mod_rewrite from the dynamic configuration files

Important: Using the dynamic configuration files (.htaccess) is a big performance hit. When you have access to the static configuration file (httpd.conf or something similar) you should use that instead. In the static configuration file, allow dynamic configuration files to override "Filei...

mod-rewrite • Getting started with mod-rewrite

Read from serial port

Initialize serial device import serial #Serial takes two parameters: serial device and baudrate ser = serial.Serial('/dev/ttyUSB0', 9600) to read single byte from serial device data = ser.read() to read given number of bytes from the serial device data = ser.read(size=5) to read one li...

Python Language • Python Serial Communication (pyserial)

Custom Renderer for BoxView

Custom Renderer help to allows to add new properties and render them differently in native platform that can not be otherwise does through shared code. In this example we will add radius and shadow to a boxview. Firstly, we should create custom control in PCL project, which will declare some requir...

Xamarin.Forms • Custom Renderers

Execute code in string format

In this exemple, we want to execute code which is stored in a string format. # the string str <- "1+1" # A string is not an expression. is.expression(str) [1] FALSE eval(str) [1] "1+1" # parse convert string into expressions parsed.str <- parse(text="1+1...

R Language • Expression: parse + eval

PHP Development Virtual Host

This is an example on how to control PHP error logging in a virtual host site for development and debugging. Assumptions The PHP module has been installed. Development environment is not for production. <VirtualHost *:80> ServerName example.com DocumentRoot /var/www/domains/e...

apache • How to create virtual host in Apache

Tutorial by Examples: o

Numbering the nodes of a tree with a counter

Old Doctypes

Converting All Tables in one Database

Configuration

Bi-Directional Many to Many using user managed join table object

Bi-Directional Many to Many using Hibernate managed join table

Bi-directional One to Many Relationship using foreign key mapping

Bi-Directional One to One Relationship managed by Foo.class

Uni-Directional One to Many Relationship using user managed join table

Uni-directional One to One Relationship

http and https redirects and HSTS configuration

Using mod_rewrite in the static configuration file

Using mod_rewrite from the dynamic configuration files

Read from serial port

Custom Renderer for BoxView

Execute code in string format

PHP Development Virtual Host

Updating the data: a basic example of enter, update and exit selections

Install crontab on Linux

Check what serial ports are available on your machine