Property Injection. 

By property injection, Dependency Injection is performed to public property.
As a example, the case where a service class is injected to an action class is shown below. In an action class, a property for service component is implemented.

<?php
class Action {

    /**
     * @var Service
     */
    public $service = null;

    /**
     * action execution method
     */
    public function execute() {
        $result = $this->service->add(2,3);    
    }
}

When the default value of a public property is regarded as null, the component which uses a property name as a key is injected. With the above-mentioned sample, the component named "service" is going to be injected.
When you do not want to be injected to the property of which default value is null, please set seasar\container\Config::$DI_PROPERTY_NULL to false.

seasar\container\Config::$DI_PROPERTY_NULL = false;

By setting default property value by type hint, the component which be injected can be specified. A type hint is described like "S2Binding component name". Moreover, two or more components can be packed as array, and DI can be carried out. When doing DI as component packed array, please specify a type hint like "S2Binding component[]".

Let's create following action class at a current directory as "classes/Action.php".

<?php
class Action {

    /**
     * @var Service
     */
    public $service = 'S2Binding Service';

    /**
     * action execution method
     */
    public function execute() {
        $result = $this->service->add(2,3);
    }
}

The component name of the default value of a property is omissible. If a component name is omitted, a property name is treated as a component name. In the following example, a component name is "service".

    /**
     * @var Service
     */
    public $service = 'S2Binding';

The key of the type hint of a property can be set up by specifying string to seasar\container\Config::$PROPERTY_TYPEHINT_KEY. If seasar\container\Config::$PROPERTY_TYPEHINT_KEY is set as "DI", the default value of a property is set up as follows. The default value of seasar\container\Config::$PROPERTY_TYPEHINT_KEY is "S2Binding".

seasar\container\Config::$PROPERTY_TYPEHINT_KEY = 'DI';

    /**
     * @var Service
     */
    public $service = 'DI Service';

Let's create following service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;
    }
}

Please generate a container using S2ApplicationContext::create method and get the action component from the container. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\container\S2ApplicationContext::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ApplicationContext::create();
$action    = $container->getComponent('Action');

$action->execute();

When generating a container using S2ContainerFactory class, please prepare the following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action"/>
    <component class="Service"/>
</components>

A container is generated using S2ContainerFactory class and an action component is taken out. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

$action->execute();

Setter Method Injection. 

By setter method injection, Dependency Injection is performed to a property using setter method. There is naming convention in a setter method. In the case that a property name is "service", first character of a head is changed into a capital letter, "set" is added to a head, then "setService" is a setter method name of "service" property.

As a example, the case where Service class is injected to Action class is shown below.
In Action class, a setter method for service component is implemented. The type hint of the argument of a setter method is be Service class. Please create following Action class at a current directory as "classes/Action.php".

<?php
class Action {

    /**
     * @var Service
     */
    private $service = null;

    /**
     * setter method of service property
     *
     * @param Service $service
     */
    public function setService(Service $service) {
        $this->service = $service;
    }

    /**
     * action execution method
     */
    public function execute() {
        $result = $this->service->add(2,3);
    }
}

Let's create following service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

As follows, a container is generated using S2ApplicationContext class and an action component is taken out from the container. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\container\S2ApplicationContext::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ApplicationContext::create();
$action    = $container->getComponent('Action');

$action->execute();

When generating a container using S2ContainerFactory class, please prepare the following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action"/>
    <component class="Service"/>
</components>

A container is generated using S2ContainerFactory class and an action component is taken out. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

$action->execute();

Constructor Injection. 

By constructor injection, Dependency Injection is performed to a property using constructor arguments.

As a example, the case where Service class is injected to Action class is shown below.
In Action class, a constructor argument for Service component is implemented. The type hint of the argument is be Service class. Let's create following Action class at a current directory as "classes/Action.php".

<?php
class Action {

    /**
     * @var Service
     */
    private $service = null;

    /**
     * construct action class
     *
     * @param Service $service
     */
    public function __construct(Service $service) {
        $this->service = $service;
    }

    /**
     * action execution method
     */
    public function execute() {
        $result = $this->service->add(2,3);
    }
}

Plese create following service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

Please generate a container using S2ApplicationContext::create method and get the action component from the container. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\container\S2ApplicationContext::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ApplicationContext::create();
$action    = $container->getComponent('Action');

$action->execute();

When generating a container using S2ContainerFactory class, please create following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action"/>
    <component class="Service"/>
</components>

A container is generated using S2ContainerFactory class and an action component is taken out. By the automatic binding function of S2Container, the service component will be injected to the action component.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/diconファイル');
$action    = $container->getComponent('Action');

$action->execute();

Property Injection. 

By property injection, Dependency Injection is performed to public property.

Setup by comment annotation. 

Let's create following action class at a current directory as "classes/Action.php". Comment annotation of each property describes the value, Expression or the reference to other component which are injected.

<?php
class Action {

    /**
     * @S2Binding('"seasar"')
     */
    public $name    = null;     // injected string "seasar"

    /**
     * @S2Binding('2000 + 8')
     */
    public $year    = null;     // injected integer "2008"

    /**
     * @S2Binding('Service')
     */
    public $service = null;     // injected Service component
}

Please create following service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;
    }
}

As follows, a container is generated using S2ApplicationContext class and an action component is taken out from the container. DI of the value and service component which were set up by annotation will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\container\S2ApplicationContext::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ApplicationContext::create();
$action    = $container->getComponent('Action');

var_dump($action);

Setup by DICON file. 

When setting up by a dicon file which is a definition file of S2Container, please create following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action">
        <property name="name">"seasar"</property>
        <property name="year">2000 + 8</property>
        <property name="service">Service</property>
    </component>
    <component class="Service" />
</components>

The property of a component is specified using the property tag which is a child tag of a component tag. A property name is specified with a name attribute. The following item can be set to the body of a property tag.

• The value surrounded by the (double) quote
• Expression which described in PHP
• Reference to other component

Let's create following action class at a current directory as "classes/Action.php".

<?php
class Action {
    public $name    = null;     // injected string "seasar"
    public $year    = null;     // injected integer "2008"
    public $service = null;     // injected Service component
}

Please create following service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

As follows, a container is generated using S2ContainerFactory class and an action component is taken out from the container. DI of the value and service component which were set up by the DICON file will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

var_dump($action);

Setter Method Injection. 

By setter method injection, Dependency Injection is performed to a property using setter method.

Setup by comment annotation. 

Lets create following Action class at a current directory as "classes/Action.php". The setter method of each property is implemented. Comment annotation of each setter method describes the value, Expression or the reference to other component which are injected. When two or more components referred to exist, DI will be done by specifying array to the type hint of a setter method. When there is no type hint, "TooManyRegistrationRuntimeException" will be thrown.

<?php
class Action {
    private $name    = null;
    private $year    = null;
    private $service = null;

    /**
     * @S2Binding('"seasar"')
     */
    public function setName($name) {
        $this->name = $name;    // injected string "seasar"
    }
    
    /**
     * @S2Binding('2000 + 8')
     */
    public function setYear($year) {
        $this->year = $year;    // injected integer "2008"
    }
    
    /**
     * @S2Binding('Service')
     */
    public function setService(Service $service) {
        $this->service  = $service     // injected Service component
    }
}

Please create following Service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

As follows, a container is generated using S2ApplicationContext class and an action component is taken out from the container. DI of the value and service component which were set up by annotation will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\container\S2ApplicationContext::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ApplicationContext::create();
$action    = $container->getComponent('Action');

var_dump($action);

Setup by DICON file. 

When setting up by a dicon file which is a definition file of S2Container, please create following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action">
        <property name="name">"seasar"</property>
        <property name="year">2000 + 8</property>
        <property name="service">Service</property>
    </component>
    <component class="Service" />
</components>

The property of a component is specified using the property tag which is a child tag of a component tag. A property name is specified with a name attribute. The following item can be set to the body of a property tag.

• The value surrounded by the (double) quote
• Expression which described PHP
• Reference to other components

When two or more components referred to exist, DI will be done by specifying array to the type hint of a setter method. When there is no type hint, "TooManyRegistrationRuntimeException" is going to be thrown.

Let's create following Action class at a current directory as "classes/Action.php". The setter method of each property is implemented.

<?php
class Action {
    private $name    = null;
    private $year    = null;
    private $service = null;

    public function setName($name) {
        $this->name = $name;    // injected string "seasar"
    }
    
    public function setYear($year) {
        $this->year = $year;    // injected integer "2008"
    }
    
    public function setService(Service $service) {
        $this->service  = $service;     // injected Service component
    }
}

Please create following Service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

As follows, a container is generated using S2ContainerFactory class and an action component is taken out from the container. DI of the value and service component which were set up by the DICON file will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

var_dump($action);

Constructor Injection. 

By constructor injection, Dependency Injection is performed to a property using constructor arguments. Let's see the following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action">
        <arg>"seasar"</arg>
        <arg>2000 + 8</arg>
        <arg>Service</arg>
    </component>
    <component class="Service" />
</components>

The argument of the constructor of a component is specified using the arg tag which is a child tag of a component tag. The following item can be set to the body of a arg tag.

• The value surrounded by the (double) quote
• Expression which described in PHP
• Reference to other component

When two or more components referred to exist, DI will be done by specifying array to the type hint of a constructor argument. When there is no type hint, "TooManyRegistrationRuntimeException" is going to be thrown.

In the constructor of Action class, three arguments are received as follows.

<?php
class Action {
    private $name    = null;
    private $year    = null;
    private $service = null;

    public function __construct($name, $year, Service $service) {
        $this->name    = $name;    // injected string "seasar"
        $this->year    = $year;    // injected integer "2008"
        $this->service = $service;     // injected service component
    }
}

Please create following Service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;
    }
}

As follows, a container is generated using S2ContainerFactory class and an action component is taken out from the container. DI of the value and service component which were set up by the DICON file will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

var_dump($action);

InitMethod Injection. 

By InitMethod injection, Dependency Injection is performed using arbitrary public method.
Let's see the following DICON file.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE components PUBLIC "-//SEASAR2.1//DTD S2Container//EN"
"http://www.seasar.org/dtd/components21.dtd">
<components>
    <component class="Action">
        <initMethod name="setName">
            <arg>"seasar"</arg>
        </initMethod>
        <initMethod name="setYear">
            <arg>2000 + 8</arg>
        </initMethod>
        <initMethod>
            $component->setService('new Service');
        </initMethod>
    </component>
</components>

InitMethod is specified by the initMthode tag which is a child tag of a component tag. The argument of a method is specified using an arg tag. The following item can be set to the body of a arg tag.

• The value surrounded by the (double) quote
• Expression which described in PHP
• Reference to other component

Let's create following Action class at a current directory as "classes/Action.php". The InitMethods are implemented.

<?php
class Action {
    private $name    = null;
    private $year    = null;
    private $service = null;

    public function setName($name) {
        $this->name = $name;    // injected string "seasar"
    }
    
    public function setYear($year) {
        $this->year = $year;    // injected integer "2008"
    }
    
    public function setService(Service $service) {
        $this->service  = $service;     // injected Service component
    }
}

Please create following Service class at a current directory as "classes/Service.php".

<?php
class Service {

    /**
     * Sums are done.
     *
     * @param integer $a
     * @param integer $b
     * @return integer
     */
    public function add($a, $b) {
        return $a + $b;    
    }
}

As follows, a container is generated using S2ContainerFactory class and an action component is taken out from the container. DI of the value and service component which were set up by the DICON file will be done.

<?php
require_once('S2Container/S2Container.php');

seasar\util\ClassLoader::import(dirname(__FILE__) . '/classes');
$container = seasar\container\S2ContainerFactory::create('/path/to/dicon file');
$action    = $container->getComponent('Action');

var_dump($action);

Table 3.1. Binding Type

autoBinding	Explanation
auto (default)	It is followed when the argument of the constructor is specified by arg tag. When the argument of the constructor is not specified, it binds automatically using type hint information. It is followed when the property is specified by property tag. When the property is not specified, it binds automatically using type hint information.
none	It is followed when the argument of the constructor is specified by arg tag. It is followed when the property is specified by property tag.

Table 3.2. Instance Type

instance	Explanation
singleton (default)	Getting of a component by S2Container::getComponent() method will return the always same instance.
prototype	A new instance is returned whenever it gets a component by S2Container::getComponent() method.